Quả Bóng Đá C60 và Ống Nano Carbon        
(Theo http://www.khoahoc.net/baivo/truongvantan/180506-ongnanocarbon.htm)

LTS: Tiến sĩ Trương Văn Tân là một cộng tác viên thường xuyên của mạng khoahoc.net. Được biết anh là một chuyên gia về vật liệu học (Materials Science) và polymer. Hơn mười năm qua anh nghiên cứu về polymer (plastic) dẫn điện và gần đây ống nano carbon. Trong bài viết nầy anh Tân giới thiệu sơ lược về nền công nghệ nano và vật liệu nano. Nhận thấy tầm quan trọng của nền công nghệ nano, Ban Biên Tập xin trân trọng giới thiệu bài viết nầy đến bạn đọc gần xa và nhất là đến các nhà khoa học tương lai của Việt Nam.

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Cách đây mười năm cụm từ "công nghệ nano" (nanotechnology) ít được người biết đến, nhưng ngày hôm nay nó trở thành một thuật ngữ quen thuộc ở mọi giai tầng trong xã hội hiện đại. Người làm kinh tế hay chính trị cũng thường đề cập đến nano dù người nói lẫn người nghe lắm khi vẫn không biết đích xác là gì. Nano là tiếng gọi tắt của nanometer (ký hiệu nm, 1 nm = 10-9 m hay là 0.000000001 m) [1] là một đơn vị đo lường ở thứ nguyên nguyên tử hay phân tử. Công nghệ nano liên quan đến việc lợi dụng những hiện tượng ở đơn vị nanometer để thiết kế vật liệu và vật chất với những chức năng đặc biệt ngay từ thang (scale) nguyên tử hoặc phân tử. Người ta gọi đây là phương pháp thiết kế "từ dưới lên" (bottom-up method) khác với phương pháp thiết kế thông thường "từ trên xuống" (top-down method) đang được lưu dụng [2]. Nhà vật lý học nổi tiếng Richard Feynman đã từng tiên đoán phương pháp "từ dưới lên" trong một bài thuyết trình năm 1959 qua câu nói vừa nghiêm túc vừa hài hước "There's plenty of room at the bottom" (Có rất nhiều chỗ trống ở miệt dưới). Lời dự đoán thiên tài nầy cho biết vùng tận cùng "miệt dưới" của nguyên tử và phân tử vẫn còn là những vùng phì nhiêu bát ngát chờ đợi con người đến thao túng khai hoang!

Tuy nhiên con người phải chờ đến 40 năm mới nhìn thấy sự bùng nổ của nền công nghệ nano chủ yếu sử dụng phương pháp "từ dưới lên". Nền công nghệ nầy đang có tác động mạnh lên nền công nghệ "cổ điển" hiện tại và cũng là một động lực của những công trình nghiên cứu đa ngành (multi-discipline) bao gồm vật lý, hóa học, vật liệu học, sinh học, toán học, tin học v.v... Đây là một cuộc cách mạng kỹ nghệ của loài người ở thế kỷ 21. Nó sẽ mang lại cho nhân loại những thay đổi khoa học kỹ thuật mang tính đột phá và có tầm ảnh hưởng sâu xa trong sinh hoạt xã hội, văn hóa, kinh tế hơn cả cuộc cách mạng kỹ nghệ ở thế kỷ 18.

Đàng sau bức bình phong công nghệ nano là những vật liệu nano. Trong những vật liệu nầy xuất hiện hai dạng carbon: phân tử fullerene C60 có hình dạng trái bóng đá và ống nano carbon (carbon nanotube). Sự phát hiện của hai dạng carbon ở thập niên 80 và 90 ở thế kỷ trước có một trùng hợp thời điểm với sự ra đời và phát triển của công nghệ nano. Việc khám phá fullerene và ống nano carbon là tập hợp của nhiều sự kiện ngẫu nhiên. Gọi là ngẫu nhiên nhưng thật ra là những kết quả hết sức ngoạn mục phản ảnh một tinh thần làm việc miệt mài nhưng vẫn phóng khoáng lạc quan, một tư duy phân tích bén nhạy nhưng không xơ cứng giáo điều của nhà khoa học.

Hiện nay, hằng trăm trung tâm nghiên cứu lớn nhỏ về công nghệ nano được thành lập khắp nơi trên thế giới đứng đầu là Mỹ, Nhật Bản, Âu Châu, Trung Quốc với kinh phí toàn cầu trong vài năm tới sẽ tăng đến hằng chục tỷ USD mỗi năm. Đối với một số nước công nghệ nano và bộ môn fullerene/ống nanocarbon là ưu tiên quốc gia cho các đề án nghiên cứu và triển khai. Trong bài viết nầy chúng ta hãy nhìn xem có thật sự là con người đang đi vào một cuộc cách mạng khoa học kỹ thuật mở ra một thời đại hoàng kim công nghệ chưa từng có trong lịch sử nhân loại. Và có thật sự là nền công nghệ silicon của thế kỷ 20 đang từ giã "cuộc hí trường" để được thay thế bởi nền công nghệ carbon.

Quả bóng đá C60

Năm 1985, một nhóm nghiên cứu bao gồm Harold Kroto (University of Sussex, Anh Quốc) và Sean O'Brien, Robert Curl, Richard Smalley (Rice University, Texas, Mỹ) khám phá ra một phân tử chứa 60 nguyên tử carbon, viết tắt là C60. Giáo sư Kroto là một nhà nghiên cứu hóa học thiên văn. Vào thập niên 70, ông đã có một chương trình nghiên cứu những chuỗi dài các nguyên tử carbon trong các đám mây bụi giữa các vì sao (interstellar dust). Ông liên lạc với nhóm của Curl và Smalley và dùng quang phổ kế laser của nhóm nầy để mô phỏng điều kiện hình thành của các chuỗi carbon trong các đám mây vũ trụ. Họ không những có thể tái tạo những chuỗi carbon mà còn tình cờ khám phá một phân tử rất bền chứa chính xác 60 nguyên tử carbon. Sự khám phá C60 xoay hướng nghiên cứu của nhóm nầy từ chuyện tìm kiếm những thành phần của vật chất tối (dark matter) trong vũ trụ đến một lĩnh vực hoàn toàn mới lạ liên hệ đến khoa vật liệu (Materials Science). Năm 1996, Kroto, Curl và Smalley được giải Nobel Hóa học cho sự khám phá nầy.

Trước C60 người ta chỉ biết carbon qua ba dạng: dạng vô định hình (amorphous) như than đá, than củi, bồ hóng (lọ nồi), dạng than chì (graphite) dùng cho lõi bút chì và dạng kim cương (Hình 1). Sự khác nhau về hình dạng, màu mè, giá cả và cường độ yêu chuộng của nữ giới giữa than đá, than chì và kim cương thì quả là một trời một vực. Tuy nhiên, sự khác nhau trong cấu trúc hóa học lại khá đơn giản. Như cái tên đã định nghĩa, dạng vô định hình không có một cấu trúc nhất định. Trong than chì các nguyên tố carbon nằm trên một mặt phẳng thành những lục giác giống như một tổ ong. Cấu trúc nầy hình thành những mặt phẳng nằm chồng chất lên nhau mang những electron pi di động tự do. Than chì dẫn điện nhờ những electron di động nầy. Trong kim cương những electron pi kết hợp trở thành những nối hóa học liên kết những mặt phẳng carbon và làm cho chất nầy có một độ cứng khác thường và không dẫn điện.


Hình 1: Tám loại carbon theo thứ tự từ trái sang phải: (a) Kim cương, (b) Than chì, (c) Lonsdaleite, (d) C60, (e) C540, (f) C70, (g) Carbon vô định hình (h) Ống nano carbon (Nguồn: Wikipedia).

Sự khám phá của C60 cho carbon một dạng thứ tư. Sau khi nhận diện C60 từ quang phổ hấp thụ Kroto, Curl và Smalley bắt đầu tạo mô hình cho cấu trúc của C60. Trong quá trình nầy các ông nhanh chóng nhận ra rằng các nguyên tố carbon không thể sắp phẳng theo kiểu lục giác tổ ong của than chì, nhưng có thể sắp xếp thành một quả cầu tròn trong đó hình lục giác xen kẻ với hình ngũ giác giống như trái bóng đá với đường kính vào khoảng 1 nm (Hình 1d và 2). Phân tử mới nầy được đặt tên là buckminster fullerene theo tên lót và họ của kiến trúc sư Richard Buckminster Fuller. Ông Fuller là người sáng tạo ra cấu trúc mái vòm hình cầu với mô dạng lục giác (Hình 3). Cho vắn tắt người ta thường gọi C60 là fullerene hay là bucky ball.


Hình 2: Quả bóng đá phân tử C60 với đường kính vào khoảng 1 nm.


Hình 3: Kiến trúc sư Richard Buckminster Fuller và mái vòm hình cầu với mô dạng lục giác.

Trong việc quyết định trao giải Nobel, Viện Hàn Lâm Khoa Học Thụy Điển đã quên mất công lao của giáo sư Eiji Osawa. Ông là người đầu tiên đã tiên đoán sự hiện hữu của C60. Tôi tình cờ gặp ông tại một cuộc hội thảo khoa học chuyên ngành. Cũng như phần lớn các giáo sư người Nhật Bản khác, giáo sư Osawa là một người khả kính, điềm đạm và khiêm tốn. Khi tôi gợi chuyện C60 và giải Nobel, ông mở nụ cười hiền hòa tâm sự "Không được Nobel tôi tiếc lắm chứ vì C60 là đứa con khoa học của tôi mà. Tôi tiên đoán C60 vào năm 1970 khi tôi vừa mới được bổ nhiệm Giảng Viên tại Đại Học Hokkaido. Vì tôi viết bằng tiếng Nhật và đăng bài báo cáo của tôi trên tạp chí Kagaku (Hóa Học) năm 1970 [3] nên không được các đồng nghiệp quốc tế lưu ý đến. Một năm sau tôi viết lại thành một chương cho một quyển sách giáo khoa, cũng bằng tiếng Nhật". Tôi hỏi "Nếu thầy đã tiên đoán như vậy thì tại sao thầy không làm một thí nghiệm để kiểm chứng". Ông bộc bạch "Theo sự tính toán của tôi thì năng lượng hoạt tính của phản ứng tạo ra C60 rất cao. Tôi không thể hình dung được một chất xúc tác nào có thể hạ thấp năng lượng hoạt tính để phản ứng có thể xảy ra. Nhưng tôi đã hình dung được cấu trúc của nó trong một lần tôi nhìn đứa con trai của tôi đùa giỡn với trái bóng đá trong công viên gần nhà. Tôi cũng không nghĩ ra một phương tiện vật lý như dùng laser hoặc tia có năng lượng cao như nhóm Smalley đã làm để kích động phản ứng. Hơn nữa, ở thời điểm đó tôi mới vừa làm Giảng Viên nên cần phải tạo một dấu ấn nào đó trong phân khoa. Tôi cảm thấy việc tổng hợp C60 quá nhiều khó khăn nên đành chọn một hướng nghiên cứu khác". Có một điều làm cho ông được an ủi phần nào là trong bài diễn văn nhận giải Nobel Kroto, Curl và Smalley đã đề cập đến thành quả tiên phong của ông. Ông đã gởi tặng tôi bài báo cáo khoa học mang tính lịch sử nầy (Hình 4).



Hình 4: Tựa đề bài báo cáo "Họ chất thơm siêu đẳng" (Super-aromaticity) viết vào năm 1970 [3] và quả bóng đá C60 trong bài viết.

Như giáo sư Osawa đã trình bày, ở điều kiện và nhiệt độ bình thường việc tổng hợp C60 là một việc bất khả thi trên phương diện nhiệt động học (thermodynamics). Vì là một nhà hóa học thiên văn, Kroto tiếp cận vấn đề bằng một phương thức khác. Tháng 9 năm 1985, trong thời gian làm việc tại Rice University ông dùng tia laser của Curl và Smalley bắn vào than chì để tái tạo sự tương tác của các tia vũ trụ và carbon trong không gian. Trong phổ ký khối lượng (mass spectrography) của các sản phẩm tạo thành xuất hiện hai đỉnh rất to chỉ định C60 và C70. Một bất ngờ nhưng Kroto, Curl và Smalley biết ngay đây là một khám phá đổi đời "kinh thiên động địa". Khi tia laser bắn vào một vùng nào đó của vật chất thì sẽ nâng nhiệt độ vùng đó lên cao hằng ngàn độ, thậm chí hằng chục ngàn độ. Ở nhiệt độ cao những chướng ngại nhiệt động học không còn là vấn đề và sự tạo thành C60 trở nên rất thuận lợi.

Việc khám phá C60 đã làm chấn động hầu hết mọi ngành nghiên cứu khoa học. Đặc biệt đối với môn hóa học hữu cơ nó đã tạo ra một nguồn sinh khí mới cho ngành nghiên cứu quá cổ điển nầy. Sự khám phá có tầm quan trọng hơn sự khám phá cấu trúc vòng nhân benzene của Kekule gần 150 năm trước. Benzene đã mở ra toàn bộ ngành hóa học của hợp chất thơm (aromatic compounds). C60 đã mở ra ngành "Hóa học fullerene" đi song song với sự phát triển của ngành công nghệ nano hiện nay.

Kroto, Curl và Smalley chỉ cho biết sự hiện hữu của C60, nhưng tổng hợp C60 cho việc nghiên cứu và ứng dụng phải đợi đến năm 1990 khi Krätschmer và Huffman đưa ra phương pháp tổng hợp với một sản lượng lớn. Nhờ vào phương pháp nầy đến năm 1997 đã có hơn 9000 hợp chất dựa trên fullerene được tổng hợp, hơn 20 000 báo cáo khoa học đăng trên các tạp chí chuyên ngành. Những người nghiên cứu hóa hữu cơ thường có nhiều nỗi ám ảnh và niềm đam mê đối với những cấu trúc phân tử đối xứng và cấu trúc lồng (cage structure), nên fullerene trở thành một lĩnh vực nghiên cứu mầu mỡ trong bộ môn nầy. Họ tổng hợp những fullerene cao hơn C60 như C70 (70 nguyên tử carbon, hình bóng bầu dục), C84 (84 nguyên tử carbon, hình quả đậu phọng). Họ kết hợp những nhóm chức (functional group) để chức năng hóa (functionalization) fullerene, gắn fullerene vào polymer để tổng hợp những dược liệu hay vật liệu cho áp dụng quang điện tử.

Lịch sử fullerene lâu đời hay non trẻ tùy vào hai cách nhìn khác nhau. Nghiên cứu fullerene thật ra rất ngắn chỉ hơn 20 năm kể từ ngày phổ ký khối lượng của Curl và Smalley cho biết sự hiện diện của C60 và C70, nhưng sự hiện hữu của fullerene có lẽ còn sớm hơn sự xuất hiện của loài người. Nó có trong những đám mây bụi trong vũ trụ, mỏ than, bồ hóng từ những ngọn nến lung linh hoặc những nơi khiêm tốn hơn như ở lò sưởi than, cái bếp nhà quê đen đui đủi vì lọ nồi... Người ta không tìm được C60 vì hàm lượng rất nhỏ và thường bị than vô định hình phủ lấp.

Khi màn bí mật C60 được vén mở, người ta nghĩ ngay đến những áp dụng thực tiễn của C60. Người ta kết hợp C60 với potassium (K) để tạo ra chất siêu dẫn hữu cơ ở nhiệt độ 18 K (-255 °C). Một số nhà nghiên cứu sinh học hy vọng có thể dùng C60 điều chế dược phẩm trị liệu bịnh AIDS. Trong vật lý, rất nhiều đề nghị áp dụng C60 để chế tạo những trang cụ (device) quang điện tử trong công nghệ cao. Tuy nhiên, trên mặt áp dụng các nhà khoa học thường mắc phải một căn bệnh chung là "lạc quan quá độ". Cấu trúc tròn trịa, đối xứng của C60 đã được tạp chí Science tôn vinh là "phân tử của năm 1991", nhưng cái xinh đẹp hấp dẫn không phải lúc nào cũng đưa đến kết quả thực tiễn hoàn mỹ.

Hai yếu tố làm C60 giảm tính thực tế là: (1) giá cả quá cao (giá cho 1 gram là vài trăm USD hoặc cao hơn cho tinh chất, so với giá vàng vào khoảng $10/g) và (2) C60 không hòa tan trong dung môi rất bất lợi cho việc gia công. Những hồ hởi ban đầu trong cộng đồng nghiên cứu khoa học dành cho fullerene bị dập tắc nhanh chóng vì những trở ngại nầy. Thậm chí ngay trong công nghệ "thấp", chẳng hạn dùng C60 như một chất phụ gia (additives) cho dầu nhớt làm giảm độ ma xát vẫn không địch nổi về giá cả và hiệu quả của những chất phụ gia thông thường. Tuần báo The Economist có lần phê bình "Cái công nghệ duy nhất mà quả bóng bucky đã thực sự cách mạng là sản xuất những bài báo cáo khoa học" (The only industry the buckyball has really revolutionized is the generation of scientific papers)!

Nhưng viễn ảnh của C60 trong áp dụng công nghệ không đến nổi tăm tối như các nhà bình luận kinh tế đã hấp tấp dự đoán. Sự kiên trì của những người làm khoa học lúc nào cũng cho thấy một niềm lạc quan của "những tia sáng ở cuối đường hầm". Gần đây công ty Nano-C (Mỹ) tuyên bố khả năng sản xuất hằng tấn C60 cho giới công nghệ. Một nhà máy thí điểm tại Nhật đang có khả năng chế tạo 40 tấn hằng năm và sẽ lên đến vài trăm tấn khi nhà máy được nâng cấp. Phương pháp sản xuất hàng loạt sẽ làm giảm giá C60 đến mức $5/g và có thể $1/g trong một tương lai không xa. Đây là một bước nhảy vĩ đại so với những năm đầu ở thập niên 90 khi người ta chỉ thu lượm vài miligram C60 ở mỗi lần tổng hợp khó khăn và giá cho mỗi gram có lúc lên đến $1500/g. Nhà sản xuất dự đoán nhu cầu C60 sẽ tăng nhanh trong vài năm tới cho việc chế biến dược liệu, dầu nhớt cao cấp và mỹ phẩm trang điểm.

Câu chuyện cô bé Lọ Lem mãi mãi là một câu chuyện tình làm thổn thức nhiều con tim trẻ. Cô bé bị bà mẹ ghẻ hành hạ lúc nào cũng phải quét dọn lò sưởi nên mặt mũi dính đầy lọ nồi. Bà Tiên với chiếc đũa thần biến nàng thành một tiểu thư đài các được trang điểm cực kỳ diễm lệ để dự những buổi khiêu vũ của chàng hòang tử độc thân đa tình. Có lẽ nàng được trang điểm với những mỹ phẩm chứa C60, nàng sẽ đeo những chuỗi kim cương carbon vô giá. Nhưng sau nửa đêm nàng sẽ trở lại cô bé đầy lọ.... Nhìn từ quan điểm của hóa học carbon, chuyện tình khi đượm tính khoa học có thể làm thất vọng nhiều tâm hồn lãng mạn nhưng tất cả chỉ là câu chuyện carbon ở những trạng thái khác nhau!

Trở lại thực tế của thế kỷ 21. Khả năng áp dụng fullerene trong công nghệ cao liên quan đến quang học và quang điện tử đang được tích cực khảo sát ở nhiều cơ quan nghiên cứu trên thế giới. Tạp chí Journal of Materials Chemistry xuất bản một số đặc biệt tổng kết những thành quả mới nhất của nghiên cứu fullerene [4]. Một trong ứng dụng có tầm quan trọng đặc biệt là đặc tính photovoltaic của C60 tức là khả năng biến năng lượng mặt trời thành điện còn gọi là pin mặt trời. Loại pin nầy được chế tạo từ C60 và polymer dẫn điện (electrically conducting polymers). Mặc dù hiệu suất chuyển hoán năng lượng vẫn chưa bì kịp pin mặt trời silicon đang được phổ biến trên thương trường, loại pin mặt trời hữu cơ nầy sẽ cho những đặc điểm không có ở silicon như dễ gia công, giá rẻ, nhẹ, mỏng và mềm.



Ống Nano Carbon

Kroto vì niềm đam mê tái tạo những chuỗi carbon dài trong các đám mây bụi vũ trụ tình cờ phát hiện fullerene. Ngẫu nhiên nầy được nối tiếp với ngẫu nhiên khác. Sáu năm sau (1991), tiến sĩ Sumio Iijima một nghiên cứu viên của công ty NEC (Nhật Bản) cũng vì niềm đam mê tìm hiểu fullerene lại tình cờ phát hiện qua kính hiển vi điện tử ống nano carbon - "người em họ" của C60 [5]. C60 có hình dạng quả bóng đá, nhưng ống nano carbon (gọi tắt: ống nano) giống như một quả mướp dài với đường kính vài nanometer (nm) và chiều dài có thể dài đến vài trăm micrometer (10-6 m), vì vậy có cái tên gọi "ống nano" (Hình 1h và 5). Với đường kính vài nm ống nano carbon nhỏ hơn sợi tóc 100 000 lần. Chỉ trong vòng vài năm từ lúc được phát hiện, "người em họ" cho thấy có rất nhiều ứng dụng thực tế hơn C60. Cấu trúc hình ống có cơ tính (mechanical properties) và điện tính (electrical/electronic properties) khác thường và đã làm kinh ngạc nhiều nhà khoa học trong các cơ quan nghiên cứu, đại học và doanh nghiệp trên thế giới. Ống nano có sức bền siêu việt, độ dẫn nhiệt cao (thermal conduction) và nhiều tính chất điện tử thú vị. Với một loạt đặc tính hấp dẫn nầy nhiều phòng nghiên cứu đã phải chuyển hướng nghiên cứu từ C60 sang ống nano.


Hình 5: Ống nano carbon

Việc chế tạo ống nano có thể thực hiện bằng cách phóng điện hồ quang (arc discharge) hoặc dùng laser (laser ablation) trên một vật liệu gốc chứa carbon hoặc phun vật liệu nầy qua một lò ở nhiệt độ 800 - 1200 °C (chemical vapour deposition, CVD). Hình thành ống carbon không phức tạp nhưng tạo ra những ống nano giống nhau cùng đặc tính trong những đợt tổng hợp khác nhau và sau đó tinh chế để gạn lọc tạp chất đòi hỏi những điều kiện vận hành một cách cực kỳ chính xác. Tùy vào điều kiện chế tạo và vật liệu gốc người ta có thể tổng hợp ống nano một vỏ (single-wall carbon nanotube, SWNT), vỏ đôi (double-wall carbon nanotube, DWNT) và nhiều vỏ (multi-wall carbon nanotube, MWNT). MWNT là một tập hợp của SWNT giống như con búp bê Nga (Russian doll) (Hình 6). Ống nano được Iijima phát hiện đầu tiên thuộc loại MWNT. Richard Smalley (Rice University) một lần nữa đã phát huy tài năng của mình qua phương pháp laser để chế tạo SWNT với hiệu suất rất cao. Phương pháp nầy đã được thương mãi hóa để sản xuất SWMT cho công nghệ. Giá cho SWNT và DWNT tinh chế vẫn còn rất cao ở mức $500/g. MWNT dễ tổng hợp hơn SWNT nên giá ở mức $100/g. Gần đây Mitsui (Nhật Bản) có thể sản xuất 120 tấn MWNT/năm cho nhu cầu công nghệ với giá $75/kg.


Hình 6: Ống nano carbon nhiều vỏ (MWNT) chụp bằng kính hiển vi điện tử. Khoảng cách giữa hai vỏ là 0.34 nm và đường kính của vỏ ngoài cùng là 6.5 nm [5].

Người ta đã định được độ bền (strength) và độ cứng (stiffness, Young's modulus) của ống nano. Kết quả thí nghiệm cho thấy ống nano bền hơn thép 100 lần nhưng nhẹ hơn thép 6 lần. Như vậy, có thể nói là ống nano là một vật liệu có cơ tính cao nhất so với các vật liệu người ta biết từ trước đến nay. Tuy nhiên, một vấn đề lớn hiện nay cho các nhà vật liệu học (materials scientist) là làm sao xe những ống nano thành tơ sợi (nanotube fibres) cho những ứng dụng thực tế mà vẫn giữ được cơ tính tuyệt vời cố hữu của các ống nano tạo thành. Nhóm nghiên cứu của giáo sư Ray Baughman (University of Texas, Mỹ) [6] đã phát minh ra một quá trình xe sợi ống nano cho ra sợi với cơ tính cao hơn thép và tương đương với tơ nhện (spider silk). Tơ nhện được biết là một loại tơ thiên nhiên có cơ tính cao nhất trong các loại tơ sợi. Kinh nghiệm cho thấy một con ruồi bay với tốc độ cao nhất vẫn không bao giờ làm thủng lưới nhện. Nếu sự kiện nầy được phóng đại vài chục ngàn lần để sợi tơ nhện có đường kính bằng cây bút chì, sợi tơ có thể kéo ngừng lại chiếc phi cơ 747 đang bay trên không!

Mặc dù độ cứng của sợi ống nano do nhóm Baughman làm ra chỉ bằng 1/10 độ cứng của từng ống nano riêng lẻ, sợi Baughman vẫn chưa phải "siêu cứng" nhưng đã hơn hẳn Kevlar [7] về sức bền và nếu điều kiện sản xuất hàng loạt cho phép nó có thể thay thế Kevlar dùng trong những chiếc áo giáp cá nhân chống đạn trong tương lai. Quá trình xe sợi của nhóm Baughman chứng tỏ khả năng chế tạo sợi ống nano với những cơ tính vĩ mô càng lúc càng gần đến cơ tính ở thang phân tử. Quá trình nầy đã kích động nhiều nhóm nghiên cứu khác trong cuộc chạy đua chế tạo ra một loại sợi siêu cứng, siêu bền và siêu hữu ích chưa từng có trong lịch sử khoa học kỹ thuật.

Với dạng hình ống dài và cơ tính lý tưởng, ống nano carbon được cho vào các loại polymer (plastic) để tạo những sản phẩm nano-composite [8]. Thật ra, composite dùng những chất độn (filler) có hình dài để tăng cơ tính không phải là những gì mới lạ. Từ 6000 năm trước nhân loại đã trộn bùn với rơm để làm gạch. Ở những vùng sâu vùng xa người dân vẫn còn dùng đất sét và rơm để làm tường. Hiện tại, chất độn kim loại hay ceramic là những vật liệu phổ biến được dùng trong polymer để tăng cường cơ tính thay thế kim loại. Người ta tin rằng ống nano carbon sẽ là một chất độn "tối thượng" cho polymer nano-composite. Vài phần trăm ống nano carbon có thể gia tăng độ bền, độ cứng và độ dai (toughness) của polymer (plastic) lên nhiều lần. Các công ty chế tạo ô tô đang triển khai polymer nano-composite cho các bộ phận xe hơi. Đặc điểm của các composite nầy là nhẹ và bền chắc. Công ty ô tô GM (Mỹ) dự trù sẽ dùng 500 tấn ống nano/năm trong vòng vài năm tới. Một cơ tính khác của ống nano đang được khảo sát hiện nay là đặc tính làm giảm sốc (shock damping), chống rung [9]. Tính chất rất quan trọng nầy sẽ mang đến những ứng dụng dân sự lẫn quốc phòng.

Điện tính và đặc tính điện tử của ống nano đã thu hút nhiều sự chú ý của các nhà vật lý và thiết kế điện tử vi mạch. Nhờ ở dạng hình ống và các electron tự do pi trong ống, các electron tự do có thể tải điện nhưng ít chịu sự phân tán electron (gọi là ballistic conduction). Sự phân tán electron là nguyên nhân điện trở gây ra sự phát nhiệt thường thấy ở chất bán dẫn hay kim loại. Nói một cách khác, ống nano có khả năng tải điện hữu hiệu vì ít phát nhiệt.

Công nghiệp điện tử được xây dựng và phát triển dựa vào kỹ thuật thu nhỏ. Transistor là một linh kiện chính trong các mạch điện. Phương pháp "từ trên xuống" đã được áp dụng để thu nhỏ transistor có độ to khoảng vài cm ở thời điểm phát minh (năm 1947) cho đến ngày hôm nay thì đến bậc nanometer; vài triệu lần nhỏ hơn. "Định luật" Moore (Moore's law) cho biết rằng cứ mỗi hai năm mật độ của các transistor được nhồi nhét vào một silicon chip sẽ tăng gấp đôi nhờ vào kỹ thuật chế biến thu nhỏ và đặc tính của silicon. Định luật đã đúng hơn 40 năm qua kể từ năm 1965 và cũng sẽ tiếp tục đúng trong vòng 10 năm tới. Lúc đó đặc tính thu nhỏ của silicon sẽ đến một mức bảo hòa và dừng lại ở một kích thước nhất định nào đó. Độ nhỏ nhất có thể đạt được của một silicon chip là 180 nm và cũng là giới hạn trong kỹ thuật làm chip hiện nay. "Độ lớn" 180 nm rất nhỏ (nhỏ hơn sợi tóc 500 lần) và hiệu năng tải điện của silicon càng giảm vì càng nhỏ sự phát nhiệt càng cao. Tuy nhiên 180 nm vẫn còn rất to so với đường kính vài nm của ống nano. Ở kích thước nầy ống nano vẫn còn có thể tải điện mà không sợ phát nhiệt. Như vậy, đặc tính tải điện không phát nhiệt và khả năng tạo thành các linh kiện điện tử như diode và transistor của ống nano ở kích thước phân tử chỉ ra một hướng nghiên cứu mới là nano-điện tử (nano-electronics) nối tiếp vai trò thu nhỏ của vi đi
          Predictive and Proactive Maintenance Techniques - Prolific Systems And Technologies Pvt. Ltd. , Dubai, Abu Dhabi, Ras al Khaimah, Doha, Riyadh, Jeddah, Dammam, Al Kuwait, Salalah, Manama, Mumbai         
Course Objective
At the end of this course participants will have:
  • An understanding of a range of Predictive Maintenance Technologies
  • Knowledge of the potential contribution of each these technologies to maintenance efficiency
  • Guidelines indicating how these technologies can interact with and support each other
  • Hints and Tips for practical application of these technologies so as to achieve the best results
  • A practical approach to developing an action plan to utilize these technologies in their own areas of responsibility, fitting them into the overall maintenance strategy, and measuring benefits
 
Key Benefits
The knowledge gained in this course will:
  • Enable the delegate to develop a proactive maintenance regime within the organization.
  • Give the delegate confidence to carry out failure analyses thereby avoiding repetitive failures.
  • Allow tighter control of maintenance budgets by the avoidance of unplanned equipment failures in service.

Who should attend?
This course is directed towards Supervisors, Team Leaders and Managers in Maintenance, Engineering and Production.
 
Program Contents:
  • Maintenance introduction
  • Types of maintenance
  • Predictive maintenance. Overview of the Predictive Maintenance philosophy and
  • Major predictive Maintenance technologies
  • CBM methodology & management, Introduction to CBM tools & techniques
  • Fault finding techniques
  • Overview of Condition Monitoring Technologies:
  • Vibration Monitoring
  • Thermography
  • Ultrasonic
  • Non Destructive Testing Technologies
Executing a Maintenance and Equipment Audit Before Starting Preventive/ Predictive Maintenance (P/PdM)
  • Determine your current maintenance productivity
  • Establish your current equipment condition and equipment performance (baseline)
  • Determine the need for preventive maintenance (PM) and predictive maintenance (PdM)
  • Calculate costs and benefits of P/PdM
Determining the Right PM System for Your Plant
  • Different types of PM
  • PM organization and staffing
PM Techniques
  • How to determine PM requirements for your equipment
  • Equipment cleaning and lubrication
  • Equipment inspections, adjustments, and servicing
How to Develop and Install a Good PM System
  • The 10-step PM installation program
  • How to keep an effective and useful equipment history
  • PM work orders/PM checklists/PM reports
How to Plan and Schedule PM and Measure PM Results
  • Determining PM frequencies and how to schedule PM
  • Time-based or usage-based scheduling
  • How to measure PM effectiveness and results
  • How to measure and analyze downtime and downtime trends
Predictive Maintenance Techniques, Applications, and Instrumentation
  • Elements of PdM (mechanical and electrical)
  • Equipment condition monitoring
  • Predicting potential equipment breakdowns or expensive repairs
Specific PdM Techniques and Applications
  • Vibration analysis/monitoring
  • Shock pulse method
  • Spectrographic oil analysis
  • Ferrographic particle analysis
  • Thermography/temperature measurement
  • Non-destructive testing (NDT)
  • Ultrasonic testing and more
Getting Organized for PdM
  • Planning for PdM; the preparatory steps
  • Starting with a PdM pilot program
  • Scheduling PdM
  • Combining PdM with PM for greatest overall effect and least cost
  • Organizational requirements
Measuring Results of PdM
  • PdM database/data collection
  • Costs of PdM (equipment/instruments, labor, and services)
  • How to determine PdM benefits and return on investment (ROI)
  • Decision factors for in-house vs. contracted PdM
Components of a Well-organized P/PdM Program
  • Equipment inventory/numbering system
  • Spare parts inventory/forecast
  • Sequence of tasks (PM and PdM routes)
  • Equipment and maintenance performance indicators and trends
Combining Planned Maintenance, PM, PdM, and TPM for Best Overall Results at the Least Costs
  • Custom-making your maintenance system based on your equipment, plant location(s), and plant size
  • Selling your solution to management (and getting the budget and management commitment)
  • Phased installation for guaranteed results
 
 

Cost:

Certified


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Twenty years ago, astronauts on the second servicing mission to the Hubble Space Telescope installed the Space Telescope Imaging Spectrograph (STIS) aboard Hubble. This pioneering instrument combines a camera with a spectrograph, which provides a "fingerprint" of a celestial object's temperature, chemical composition, density, and motion. STIS also reveals changes in the evolving universe and leads the way in the field of high-contrast imaging. The versatile instrument is sensitive to a wide range of wavelengths of light, from ultraviolet through the optical and into the near-infrared. From studying black holes, monster stars, and the intergalactic medium, to analyzing the atmospheres of worlds around other stars, STIS continues its epic mission to explore the universe.


          Hubble Captures Vivid Auroras in Jupiter's Atmosphere        

Astronomers are using NASA's Hubble Space Telescope to study auroras — stunning light shows in a planet's atmosphere — on the poles of the largest planet in the solar system, Jupiter. The auroras were photographed during a series of Hubble Space Telescope Imaging Spectrograph far-ultraviolet-light observations taking place as NASA's Juno spacecraft approaches and enters into orbit around Jupiter. The aim of the program is to determine how Jupiter's auroras respond to changing conditions in the solar wind, a stream of charged particles emitted from the sun. Auroras are formed when charged particles in the space surrounding the planet are accelerated to high energies along the planet's magnetic field. When the particles hit the atmosphere near the magnetic poles, they cause it to glow like gases in a fluorescent light fixture. Jupiter's magnetosphere is 20,000 times stronger than Earth's. These observations will reveal how the solar system's largest and most powerful magnetosphere behaves.

The full-color disk of Jupiter in this image was separately photographed at a different time by Hubble's Outer Planet Atmospheres Legacy (OPAL) program, a long-term Hubble project that annually captures global maps of the outer planets.


          Water-rich Planetary Building Blocks Found Around White Dwarf        

If you go walking along the beach or take an ocean cruise, it's hard to believe that Earth is essentially a "dry" planet. Barely 0.02 percent of our home planet's mass is surface water. In fact, our oceans came along a few hundred million years after Earth formed 4.6 billion years ago. Though still debated, astronomers think that the primeval Earth was most likely irrigated when water-rich asteroids in the solar system crashed into our planet.

Now astronomers have found that the same water "delivery system" could have occurred in a dying star's planetary system. Hubble Space Telescope spectroscopic observations have found forensic evidence for the same kind of water-rich asteroids that may have once brought water to Earth. Observations made with Hubble's Cosmic Origins Spectrograph (COS) allowed the team of astronomers to do a robust chemical analysis of debris falling into the white dwarf star GD 61, located 150 light-years from Earth. They didn't detect planets but the building blocks of planets. The asteroids are plummeting deep into the gravitational field of the white dwarf, presumably due to gravitational perturbations from a surviving Jupiter-sized planet in the system. This is circumstantial evidence that potentially habitable planets once existed in this star system. However, the star burned out 200 million years ago.


          Hubble Finds Dead Stars 'Polluted' with Planet Debris        

Deep inside the Hyades star cluster, a pair of burned-out stars are yielding clues to the presence of rocky planets that may have whirled around them. Asteroid debris is 'raining' into the hot atmospheres of these white dwarfs. Asteroids should consist of the same material that form terrestrial planets, and seeing evidence of asteroids points to the possibility of Earth-sized planets in the same system.

Hubble's Cosmic Origins Spectrograph observed silicon and only low levels of carbon in the white dwarfs' atmospheres. Silicon is a major ingredient of the rocky material that constitutes Earth and other solid planets in our solar system. Astronomers used sophisticated computer models of white dwarf atmospheres to determine the abundances of various elements that can be traced to planets in the Hubble spectrograph data.


          NASA's Hubble Confirms that Galaxies Are the Ultimate Recyclers        

Galaxies learned to "go green" early in the history of the universe, continuously recycling immense volumes of hydrogen gas and heavy elements to build successive generations of stars stretching over billions of years. In other words they are more fuel efficient than any hybrid car on the road. This ongoing recycling keeps galaxies from emptying their "fuel tanks" and therefore stretches out their star-forming epoch to over 10 billion years. The catch is that those galaxies that crank up the rate of star formation can blow away their remaining fuel, essentially turning off further star-birth activity. But galaxies like our Milky Way that frugally pace the rate of star birth can go on building new stars at least one billion years into the future.

This conclusion is based on a series of Hubble Space Telescope observations that flexed the special capabilities of its comparatively new Cosmic Origins Spectrograph (COS) to detect otherwise invisible mass in the halo of our Milky Way and a sample of more than 40 other galaxies. The three studies investigated different aspects of the gas-recycling phenomenon in galaxies. The results are being published in three papers in the November 18 issue of Science magazine.


          Space Telescopes Reveal Secrets of Turbulent Black Hole        

An international team of astronomers using five different telescopes has uncovered striking features around a supermassive black hole in the core of the distant galaxy Markarian 509. They found a very hot corona hovering above the black hole and cold gas "bullets" in hotter diffuse gas, speeding outward with velocities over 1 million miles per hour. This corona absorbs and reprocesses the ultraviolet light from the accretion disk encircling the black hole, energizing it and converting it into X-rays. This discovery allows astronomers to make sense of some of the observations of active galaxies that have been hard to explain so far. The heart of the campaign consisted of repeated visible, X-ray, and gamma-ray observations with ESA's XMM-Newton and INTEGRAL satellites, which monitored Markarian 509 for six weeks. This was followed by long observations with NASA's Chandra X-ray Observatory and the Hubble Space Telescope. Prior to these observations short snapshots to monitor the behavior of the source at all wavelengths were taken with NASA's Swift satellite. The combined efforts of all these instruments gave astronomers an unprecedented insight into the core of an active galaxy.

The Cosmic Origins Spectrograph aboard Hubble reveals that the coolest gas in the line of sight toward Markarian 509 has 14 different velocity components at various locations in the innermost parts of this galaxy. Hubble's data, combined with X-ray observations, show that most of the visible outflowing gas is blown off from a dusty gas disk surrounding the central region more than 15 light-years away from the black hole. This outflow consists of dense, cold blobs or gas bullets embedded in hotter diffuse gas. The international consortium responsible for this campaign consists of 26 astronomers from 21 institutes on 4 continents. The first results of this campaign will be published as a series of seven papers in the journal Astronomy and Astrophysics. More results are in preparation.


          Fast Falling Clouds Fuel Milky Way Star Formation        

The long-term forecast for the Milky Way is cloudy with gaseous rain. A study by Nicolas Lehner and Christopher Howk of the University of

Notre Dame concludes that massive clouds of ionized gas are raining down

from our galaxy's halo and intergalactic space and will continue

to provide fuel for the Milky Way to keep forming stars. Using the Hubble Space Telescope's Cosmic Origins Spectrograph they measured for the first time the distances to huge, fast-moving clouds of ionized gas previously seen covering a large fraction of the sky.


          Hubble Astronomers Uncover an Overheated Early Universe        

If you think global warming is bad, 11 billion years ago the entire universe underwent, well, universal warming. The consequence was that fierce blasts of radiation from voracious black holes stunted the growth of some small galaxies for a stretch of 500 million years. Astronomers used the Hubble Space Telescope's Cosmic Origins Spectrograph (COS) to identify an era, from 11.7 to 11.3 billion years ago, when the universe burned off a fog of primeval helium. This heated intergalactic gas was inhibited from gravitationally collapsing to form new generations of stars in some small galaxies.

The telltale helium spectral absorption lines were measured in the ultraviolet light from a quasar – the brilliant core of an active galaxy. The quasar beacon shines light through intervening clouds of invisible gas, like a headlight shining through a fog. The beam allows for a core-sample probe of the clouds of gas interspersed between galaxies in the early universe. The universe was a rambunctious place back then. Giant galaxies frequently collided. This engorged supermassive black holes in the cores of galaxies with infalling gas. The black holes furiously converted some of this mass to powerful far-ultraviolet radiation that would blaze out of galaxies. This heated intergalactic helium from 18,000 degrees Fahrenheit to nearly 40,000 degrees. Only after the helium cooled down could small galaxies resume normal assembly.


          Superhot Planet Likely Possesses Comet-like Tail        

As if the debate over what is and what is not a planet hasn't gotten confusing enough, Hubble Space Telescope astronomers have now confirmed the existence of a tortured, baked object that could be called a "cometary planet." The gas giant planet, dubbed HD 209458b, is orbiting so close to its star that its heated atmosphere is escaping away into space. Now, observations by the new Cosmic Origins Spectrograph (COS) aboard NASA's Hubble suggest that powerful stellar winds are sweeping the castoff material behind the scorched planet and shaping it into a comet-like tail.

This artist's illustration shows a view of HD 209458b, as seen from the surface of a hypothetical nearby companion object.


          Hubble Finds Star Eating a Planet        

"The Star That Ate My Planet" may sound like a B-grade science fiction movie title, but this is really happening 600 light-years away. Like a moth in a candle flame, a doomed Jupiter-sized planet has moved so close to its sunlike parent star that it is spilling its atmosphere onto the star. This happens because the planet gets so hot that its atmosphere puffs up to the point where the star's gravity pulls it in. The planet will likely be completely devoured in 10 million years. Observations by Hubble's new Cosmic Origins Spectrograph measured a variety of elements in the planet's bloated atmosphere as the planet passed in front of its star. The planet, called WASP-12b, is the hottest known world ever discovered, with an atmosphere seething at 2,800 degrees Fahrenheit.


          Hubble Opens New Eyes on the Universe        

NASA's Hubble Space Telescope is back in business, ready to uncover new worlds, peer ever deeper into space, and even map the invisible backbone of the universe. The first snapshots from the refurbished Hubble showcase the 19-year-old telescope's new vision. Topping the list of exciting new views are colorful multi-wavelength pictures of far-flung galaxies, a densely packed star cluster, an eerie "pillar of creation," and a "butterfly" nebula. With its new imaging camera, Hubble can view galaxies, star clusters, and other objects across a wide swath of the electromagnetic spectrum, from ultraviolet to near-infrared light. A new spectrograph slices across billions of light-years to map the filamentary structure of the universe and trace the distribution of elements that are fundamental to life. The telescope's new instruments also are more sensitive to light and can observe in ways that are significantly more efficient and require less observing time than previous generations of Hubble instruments. NASA astronauts installed the new instruments during the space shuttle servicing mission in May 2009. Besides adding the instruments, the astronauts also completed a dizzying list of other chores that included performing unprecedented repairs on two other science instruments.

Now that Hubble has reopened for business, it will tackle a whole range of observations. Looking closer to Earth, such observations will include taking a census of the population of Kuiper Belt objects residing at the fringe of our solar system, witnessing the birth of planets around other stars, and probing the composition and structure of the atmospheres of other worlds. Peering much farther away, astronomers have ambitious plans to use Hubble to make the deepest-ever portrait of the universe in near-infrared light. The resulting picture may reveal never-before-seen infant galaxies that existed when the universe was less than 500 million years old. Hubble also is now significantly more well-equipped to probe and further characterize the behavior of dark energy, a mysterious and little-understood repulsive force that is pushing the universe apart at an ever-faster rate.


          The Colorful Lives of the Outer Planets        

Atmospheric features on Uranus and Neptune are revealed in images taken with the Space Telescope Imaging Spectrograph and the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope. A wider view of Uranus, taken with the Advanced Camera for Surveys, reveals the planet's faint rings and several of its satellites. The observations were taken in August 2003.


          Hubble Picture Adds to Planet-Making Recipe        

The Hubble telescope has snapped a nearly face-on view of a swirling disk of dust and gas surrounding a developing star called AB Aurigae. The image, taken in visible light by the Space Telescope Imaging Spectrograph, shows unprecedented detail in the disk, including clumps of dust and gas that may be the seeds of planet formation.

Normally, a young star's bright light prevents astronomers from seeing material closer to it. That's why astronomers used a coronograph in these two images of AB Aurigae to block most of the star's glare. The rest of the disk material is illuminated by light reflected from the gas and dust surrounding the star. The image on the left represents the best ground-based coronographic observation of AB Aurigae. The star resides in a region of dust clouds ? the semicircular-shaped material to the left of the star. The Hubble telescope image on the right shows a windowpane-shaped occulting bar. The illuminated material surrounding the star is the dust disk.


          Hubble Shoots the Moon        

In a change of venue from peering at the distant universe, the Hubble telescope has taken a look at Earth's closest neighbor in space, the Moon. Hubble was aimed at one of the Moon's most dramatic and photogenic targets, the 58-mile-wide (93-kilometer) impact crater Copernicus.

The image was taken while the Space Telescope Imaging Spectrograph was aimed at a different part of the moon to measure the colors of sunlight reflected off the Moon. The picture at upper left is a full view of the moon taken by a terrestrial telescope. The wide, central image is Hubble's crisp, bird's-eye view, which clearly shows the ray pattern of bright dust ejected out of the crater over one billion years ago when an asteroid larger than a mile across slammed into the Moon. A close-up view of Copernicus's terraced walls is shown at lower right.


          Mysterious Fireball From A Cataclysmic Explosion        

The visible fireball from a titanic explosion in deep space, called a gamma-ray burst, blazes in the center of this image, taken with the Hubble telescope's imaging spectrograph.

The burst occurred on May 8, 1997, and Hubble observations to acquire the fading fireball were made on June 2. No accompanying object, such as a host galaxy, can be found near the burst. This result adds to the puzzlement over the source of these enigmatic explosions, because a previous Hubble picture of the visible glow from another gamma-ray burst identified a potential host galaxy.


          Hubble Reveals Invisible High-Speed Collision around Supernova 1987A         

The highest velocity material expelled in a cataclysmic, stellar explosion 10 years ago has been detected for the first time by the Hubble telescope's imaging spectrograph.

The top image, taken with Hubble's visible-light camera, shows the orange-red rings surrounding Supernova 1987A in the Large Magellanic Cloud. The glowing debris of the supernova explosion, which occurred in February 1987, is at the center of the inner ring. The small, white square indicates the location of the imaging spectrograph aperture. The Hubble data in the middle panel [and a schematic representation in the bottom panel] shows the presence of glowing hydrogen expanding at a speed of 33 million mph (15,000 kilometers per second) coming from an extended area inside the inner ring.


          Fireworks Near a Black Hole in the Core of Seyfert Galaxy NGC 4151         

The Hubble telescope's imaging spectrograph simultaneously records, in unprecedented detail, the velocities of hundreds of gas knots streaming at hundreds of thousands of miles per hour from the nucleus of NGC 4151, thought to house a super-massive black hole. This is the first time the velocity structure in the heart of this object, or similar objects, has been mapped so vividly this close to its central black hole.

The heart of NGC 4151 was captured in visible light in the upper left picture. In the other images, Hubble's imaging spectrograph has zeroed in on the galaxy's active central region. The Hubble data clearly show that the some material in the galaxy's hub is rapidly moving towards us, while other matter rapidly receding from us. This information is strong evidence for the existence of a black hole, an extremely compact, dense object that feeds on material swirling around it.


          Hubble Chemically Analyzes the Ring around Supernova 1987A        

These pictures from the Hubble telescope's imaging spectrograph provide a new and unprecedented look at one of the most unique and complex structures in the universe – a light-year-wide ring of glowing gas around supernova 1987A, the nearest stellar explosion in 400 years

The long-slit spectrograph viewed the entire ring system, dissecting its light and producing a detailed image of the ring in each of its component colors [the colorful loops on the right]. Each color represents light from specific elements in the ring's gases, including oxygen [single green ring], nitrogen and hydrogen [triple-orange rings], and sulfur [double-red rings]. By dismantling the ring into its different puzzle pieces – its component elements – astronomers hope to put together a picture of how the ring was created. The picture on the left is a view of the entire supernova.


          Hubble Records a Black Hole's Signature         

The colorful "zigzag" on the right is not the work of a flamboyant artist, but the signature of a super-massive black hole in the center of galaxy M84, discovered by the Hubble telescope's imaging spectrograph.

The image on the left, also taken by Hubble, shows the core of the galaxy where the suspected black hole dwells. In a single exposure, astronomers mapped the motions of gas in the grip of the black hole's powerful gravitational pull by aligning Hubble's spectroscopic slit across the nucleus.


          Hubble Finds Ozone on Jupiter's Moon Ganymede        

Though ozone may be diminishing on Earth, it is being manufactured one-half billion miles away, on Jupiter's largest satellite, Ganymede.

NASA's Hubble Space Telescope found ozone's spectral "fingerprint" during observations of Ganymede made by Keith Noll and colleagues at the Space Telescope Science Institute in Baltimore, Maryland. These Hubble Faint Object Spectrograph results were presented at the American Astronomical Society's 27th Annual Meeting of the Division of Planetary Sciences in Kona, Hawaii.


          Artist's Illustration of Beta Pictoris Gas Disk        

This is an artist's concept of the near stellar environment of the star Beta Pictoris. This illustration is based upon recent observations made with the Goddard High Resolution Spectrograph aboard the Hubble Space Telescope.


          By: Nathan Pieplow        
David, it's great to hear from you here, and I appreciate your account of your experience, which is different than mine. To answer Eric's question, I have (on more than one occasion) followed a pre-dawn "Buff-collared Nightjar" vocalization to its source and found not a Cassin's Kingbird, but a Vermilion Flycatcher -- and consequently I've been taken aback by the literature's frequent references to confusion with Cassin's (only). My focus on Vermilion as the confusion species may be due to my tendency to focus on the pattern of bird sounds more than on their tone quality. At any rate, David, it's enlightening to hear that you actually did confuse Cassin's with Buff-collar in the field...it broadens my thinking about these birds, and about the chain of literature citations that I followed in writing this post. On the subject of error propagation: the spectrographic figure in the BNA account of Cassin's Kingbird labels something other than the dawn song as the dawn song. The text, however, is accurate. I've noticed several of these discrepancies in BNA -- as I recall, the Say's Phoebe account has a similar issue. I believe these errors are infrequently spotted because 1) relatively few people research sounds and 2) many people still aren't comfortable matching spectrograms to sounds. Yet another area of potential ornithological expertise crying out for more people to fill it. :)
          Space Storm Measurements of 17 and 21 April 2002 Forbush Effects from Artemis-IV Solar Radio-Spectrograph, Athens Neutron Monitor Station and Coronas-F Satellite        
Дата и время публикации : 2010-09-19T17:00:02Z Авторы публикации и институты : C. Caroubalos X. Moussas P. Preka-Papadema A. Hillaris I. Polygiannakis H. Mavromichalaki C. Sarlanis G. Souvatzoglou M. Gerontidou C. Plainaki S. Tatsis S. N. Kuznetsov I. N. Myagkova K. Kudela Ссылка на журнал-издание: 2004hell.conf…81CКоментарии к cтатье: Hellenic Astronomical Society: Proceedings of the Sixth Astronomical [...]
          GYES, a multifibre spectrograph for the CFHT        
Дата и время публикации : 2010-09-19T15:38:33Z Авторы публикации и институты : P. Bonifacio (GEPI, Observatoire de Paris, CNRS, Univ. Paris Diderot) S. Mignot (GEPI, Observatoire de Paris, CNRS, Univ. Paris Diderot) J. -L. Dournaux (GEPI, Observatoire de Paris, CNRS, Univ. Paris Diderot) P. François (GEPI, Observatoire de Paris, CNRS, Univ. Paris Diderot) E. Caffau (GEPI, [...]
          The improved ARTEMIS IV multichannel solar radio spectrograph of the University of Athens        
Дата и время публикации : 2010-09-19T10:34:35Z Авторы публикации и институты : A. Kontogeorgos P. Tsitsipis C. Caroubalos X. Moussas P. Preka-Papadema A. Hilaris V. Petoussis C. Bouratzis J-L Bougeret C. E. Alissandrakis G. Dumas Ссылка на журнал-издание: 2006ExA….21…41KКоментарии к cтатье: Experimental Astronomy, Volume 21, Issue 1, pp.41-55Первичная категория: astro-ph.IM Все категории : astro-ph.IM Краткий обзор [...]
          A nearby Sun-like star hosts four Earth-sized planets        

Exoplanet discoveries are getting pretty common, so it takes something special to catch our attention. A star called Tau Ceti fits the bill, as it's just 12 light years away and unlike the Trappist-1 red dwarf, is very similar to our own yellow dwarf (G-type) sun. Researchers have determined that it probably hosts planets like Earth that sit in its habitable zone. The only hitch is that the star is known to have a massive debris disk that probably bombards its worlds with asteroids, so living there would be a pretty big challenge.

Four rocky worlds were found, with two in the habitable zone, about 0.5 and 1.25 times as far from their star as the Earth is from the Sun. That works out well, as Tau Ceti is a bit smaller (78 percent) than the Sun, and is correspondingly less intense. The smallest of the worlds is about 1.7 times the size of Earth, but the habitable zone planets are much larger "super Earths" that could potentially support life.

However, Tau Ceti is known to have a big debris disk that probably produces far more impact events via comets and asteroids than we have on Earth. While that makes life improbable, the discovery is still important because of the techniques used.

On smaller stars, planets can be detected by the "transit method," observing the dimming of light as planets pass in front. That doesn't work as well for bigger stars like Tau Ceti though, as the light levels drown out any dimming.

The W.M. Keck HIRES-MAGIQ detector

Instead, the team observed wobbles in the star's movement as small as 30 centimeters (one foot) per second. That has only become possible recently by combining multiple observations from different instruments and sophisticated modeling. In this case, the team obtained observations from the HARPS spectrograph on the European Southern Observatory in Chile, and Keck HIRES (above) on the W.M. Keck Observatory in Mauna Kea, Hawaii.

"We can [now] disentangle the noise due to stellar surface activity from the very tiny signals generated by the gravitational tugs from Earth-sized orbiting planets," said UC Santa Cruz Professor and co-author Steven Vogt. "Our detection of such weak wobbles is a milestone in the search for Earth analogs."

Using the new techniques, the same team actually ruled out two planets they previously identified in 2013 as planets. "But no matter how we look at the star, there seem to be at least four rocky planets orbiting it," said coauthor Mikko Tuomi.

We can disentangle the noise due to stellar surface activity from the very tiny signals generated by the gravitational tugs from Earth-sized orbiting planets. Our detection of such weak wobbles is a milestone in the search for Earth analogs.

The team hopes to refine the techniques to find wobbles as small as 10 cm (4 inches) per second, small enough to detect Earth-sized planets. That could be crucial, because while its easier to spot exoplanets around dim red dwarf stars like Trappist-1 using the transit method, astronomers are beginning to wonder if such stars can actually support life.

Planets tend to get tidally locked to red dwarf stars early in their life because their years are so short -- often a week or less. As a result, much like our moon is to the Earth, one side is constantly exposed to radiation and the other is in the dark. "Because of the onslaught by the star's radiation, our results suggest the atmosphere on planets in the Trappist-1 system would largely be destroyed," said researcher Avi Loeb.

That makes the likelihood of life just one percent compared to Earth. Since life has enough challenges already, it's probably got a much better shot on a planet around a type-G, main sequence star. We know for a fact that those can support life, as here we are.


          Telescopes for Sale For All Budding Astronomers        
If you are a beginner astronomer or a practiced stargazer, when it comes to considering new and used telescopes for sale, it's easy to get a little bamboozled by all the choices available.
There are many factors to look at in choosing which telescope is most suitable for your purposes.
When you research telescopes for sale, how do you know what to look for? Is aperture the key consideration? What's the best brand? How much should you pay?
Acquiring an understanding of the key workings of telescopes can aid you in making the right choice and perhaps even save you money by getting the right scope for the right job.

The telescope is specifically designed as an optical instrument and most rely on visible light to perform their primary function.
However, there are similar instruments that utilize other parts of the electromagnetic radiation spectrum to supply images for various purposes such as the radio telescope that focus radio waves, and the X-ray and gamma-ray telescopes.

The objective of your essential telescope is to focus visible light (as well as other electromagnetic radiation) so as to increase the angular size of far-off objects and also their perceptible brightness. Depending on their design and style, most telescopes use curved optical elements such as lenses or mirrors to collect light and bring it to a focus providing a means for the viewer to observe, photograph or study the image.

Optical Telescopes

Optical telescopes are utilized in astronomy as well as in non-astronomical instruments such as theodolites, transits, spotting scopes, monocular, binoculars, camera lenses as well as spyglasses.

These instruments are generally named after their designers. There are three main types of telescopes, generally used for astronomical purposes, and these are the refracting telescope, the reflecting telescope and the catadioptric telescopes.

The refracting instrument uses is composed of an arrangement of lenses while the reflecting telescope uses only mirrors, and the catadioptric telescopes use both elements of mirrors plus lenses.

For human eye viewing, one will usually need an arrangement of lenses and so the refractive telescope is the obvious selection for most recreational stargazers.

If you are interested in telescopes for sale for use in astronomy, image rendering is performed with the support of photographic film or digital sensors These telescopes normally do not demand an eyepiece and so are usually reflector telescopes.

There are also research telescopes that are either a Cassegrain or a Newtonian telescope. With the Multiple Mirror Telescope, a new age in this type of instrument has arrived, and with more scientific inquiry, there will be many other advancements added such as imagers, spectrographs, and polarimeters.

And new technology is also making strides in overcoming distortions induced by the earths atmosphere on such ground-based instruments.

There are several key things to take into account when weighing up the best telescope for your purposes.

It can be debated that the telescope aperture is the most important aspect to consider when looking at buying telescopes. It is the aperture which determines the amount of light getting into the telescope and the general brightness of the image and sharpness of everything.

If you are like me, it is possible to get carried away and buy a larger aperture telescope only to find it is simply too big to carry comfortably for field observations. There is much to think about..
          Special Notice #297: HST COS observations of SDSS J164248.52+134751.4 scheduled        

October 5, 2012:  Following on AAVSO Alert Notice 471 (Gaensicke, Patterson, and Henden, www.aavso.org/aavso-alert-notice-471), the HST COS (Cosmic Origins Spectrograph) far ultraviolet observations of the cataclysmic variable SDSS J164248.52+134751.4 have been scheduled for 2012 October 12 from 01:03:27 to 06:21:43 UT. Extensive coverage in the 48 hours preceding the HST window is crucial, as the HST scheduling team will make a go/no-go decision in the 24 hours preceding the observations. They will need to know whether the system is in quiescence, as if it is too bright it will damage the instrumentation and the observations will be cancelled.

Positive observations, if at all possible, are preferred to fainter-thans so as to know the actual magnitude of the system. During quiescence SDSS J164248.52+134751.4 is around magnitude V=18.6.

Coordinates:  R.A. 16 42 48.51     Dec. +13 47 51.5  (2000.0)

As instructed in Alert Notice 471, for CCD observers, simultaneous photometry [shortly before, during, and after the HST observations] would be ideal. B filter would be best for a light curve, although for the magnitude estimates, a V measurement would be best. An uninterrupted light curve would be better than cycling between filters. This target is likely too faint for positive visual observations, but if possible they are welcome, as are visual fainter-than observations fainter than magnitude 15.0.

Charts for SDSS J164248.52+134751.4 may be created using VSP (www.aavso.org/vsp).

Please report observations promptly to the AAVSO International Database using the name SDSS J164248.52+134751.4. If you see the target in outburst, please contact the AAVSO immediately and post a message to the Observations and Campaigns & Observations Reports forum (http://www.aavso.org/forum).

Your observations will be crucial to the success of these observations and are greatly appreciated. Many thanks!

This AAVSO Special Notice was compiled by Elizabeth O. Waagen.

-------------------------------------------------
SUBMIT OBSERVATIONS TO THE AAVSO

Information on submitting observations to the AAVSO may be found at:
http://www.aavso.org/webobs

SPECIAl NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION

A Special Notice archive is available at the following URL:
http://www.aavso.org/special-notice-archive

Subscribing and Unsubscribing may be done at the following URL:
http://www.aavso.org/observation-notification#specialnotices


          Applied Physics/Physics Colloquium        

Optical frequency combs are providing powerful tools for laser spectroscopy. Mode-locked femtosecond lasers and related emerging miniaturized devices can produce a large number of precisely evenly spaced spectral lines. Almost two decades ago, such spectral combs were introduced as tools for optical frequency metrology, motivated by the challenges of precision laser spectroscopy of atomic hydrogen as tests for fundamental physics laws. Current precision spectroscopy of hydrogen with frequency combs focuses on the "proton size puzzle", i.e. the discrepancy between the rms proton charge radius determined from Lamb shift measurements in ordinary hydrogen and in muonic hydrogen. Laser frequency combs provide the long-missing clockwork for optical atomic clocks, which are now approaching relative frequency uncertainties of 10-18. Distant clocks can be compared via optical fiber links at the 10-19 level, opening new opportunities for relativistic geodesy and astronomical interferometry. Frequency combs in space will permit new tests of Einstein's equivalence principle. As calibration tools for astronomical spectrographs, frequency combs are facilitating the search for exoplanets, and they may lead to direct evidence for the accelerating expansion of space in our universe. Laser combs are also enabling novel broadband molecular spectroscopy. They can dramatically improve the resolution and recording speed of Fourier spectrometers, and they are creating intriguing new opportunities for highly multiplexed nonlinear spectroscopy and microscopy.


 

Held Tuesdays at 4:30 pm in the William R. Hewlett Teaching Center, room 201.

Refreshments in the lobby of Varian Physics at 4:15 pm.

Spring 2015/2016, Committee: M. Schleier-Smith (Chair), G. Gratta, B. Lev, S. Zhang

 

 
 

           Galaxy and Mass Assembly (GAMA): Optimal Tiling of Dense Surveys with a Multi-Object Spectrograph         
Robotham, A., Driver, S. P., Norberg, P., Baldry, I. K., Bamford, S. P., Hopkins, A. M., Liske, J., Loveday, J., Peacock, J. A. et al (2010) Galaxy and Mass Assembly (GAMA): Optimal Tiling of Dense Surveys with a Multi-Object Spectrograph. Publications of the Astronomical Society of Australia, 27 (1). p. 76. ISSN 1323-3580
          Announcing the Candidates for 2016 AAVSO Council Elections        

Slate of candidates for AAVSO Council elections to be held November 2016

Richard Berry, Lyons, Oregon
Tom Calderwood, Bend, Oregon
David Gagnon, Nantucket, Massachusetts
Mike Joner, Provo, Utah
Katrien Kolenberg, Heverlee, Belgium -  *running for re-election
Linda Morgan-O’Connor, Danforth, Maine
Richard S. Post, Lexington, Massachusetts
Gregory R. Sivakoff, Edmonton, Alberta, Canada

 

Biographical statements from candidates

Richard Berry, Lyons, Oregon

I am running for Council because I support the goals and work of the AAVSO.  I want to see the organization operating on a solid financial base, growing in membership, continuing to make a significant contribution to the science of astronomy, and reaching out to the next generation of amateur and professional astronomers now in grade schools, high school, and college.

Telescopes, instruments, and precise measurement have always fascinated me.  While in junior high school, I became an avid telescope maker (culminating in a 12-inch Newtonian), got into astrophotography, constructed a spectrograph, and in 1964, measured the light curve of a lunar eclipse using a Clairex photocell at the focus of a 6-inch f/2 mirror.  After earning my BA (UVa) and MSc (York U), my work involved designing and building instruments for aurora research, optical air-pollution measurement, and the Apollo-Soyuz mission.

In 1976, I changed careers, joining the staff of ASTRONOMY as Technical Editor, and worked my way up to Editor-in-Chief.  In that role, I spent 16 years editing, writing, and promoting the enjoyment of astronomy at all levels.  I take pride in having built the solid editorial team that has taken ASTRONOMY from a struggling start-up with a minuscule budget to a profitable, large-circulation monthly magazine.

As a freelance writer, I wrote my first book, Build Your Own Telescope, followed by The Dobsonian Telescope, The CCD Camera Cookbook, The Handbook of Astronomical Image Processing, and Telescopes, Eyepieces, and Astrographs.  As a fledgling software developer, I created a succession of programs for image processing back in the days of MS-DOS.  My later program, Astronomical Image Processing for Windows (AIP4Win), is still widely used for CCD photometry by members of the AAVSO.

As a member of Council, I will work to see the current assets of the AAVSO employed fully and efficiently, and to help the AAVSO build membership, do great science, and serve as a resource for the astronomical community.

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Tom Calderwood, Bend, Oregon
I am a retired software engineer with a lifelong enthusiasm for astronomy.  Having taken up residence in the comparatively clear and dark skies of Central Oregon, I am finally able to practice photometry with my photoelectric equipment.  My career projects encompassed parallel
processing computers, satellite and terrestrial communication networks, video games, and remote sensing.  But more to the point, I spent nine years at the Harvard-Smithsonian Center for Astrophysics, working on the data system for the Chandra X-ray Observatory.  Education-wise, I have a BS in mathematics from MIT.  I've built two reflecting telescopes, one of which earned an optical 2nd prize at Stellafane.

I have been involved in outreach for many years.  I participated in Project Astro, and twice served as an “Astronomy VIP” at Acadia National Park, where I helped the staff ramp up a public viewing program.  I've lost count of the star parties I organized or supported.  I presently help with outreach at Pine Mountain Observatory near Bend, where I assist with public programs and lead high school students during the annual week-long astronomy workshop.  Last year's workshop produced the JAAVSO paper, “Simultaneous Collocated Photometry”.

My interests in serving on the Council are two-fold.  First, I want to address the sustainability of the association's computing infrastructure (“CI”).  This includes the main database, the web presence, data reduction pipelines, and the embedded systems at remote sites.  Second, I want to address the quality of our photometric data (inter-observer consistency is presently the main thrust of my own observing program).  I believe both of these areas are crucial as the AAVSO accumulates ever more electronic measurements.

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David Gagnon, Nantucket, Massachusetts

 I am currently the Executive Director of the Nantucket Maria Mitchell Association (MMA).  Founded in memory of America’s first women astronomer, Maria Mitchell, our association has been conducting important astronomical research on the island of Nantucket for well over a hundred years.  The MMA is most noted for its long history of training women in the field of astronomy.  Each summer, six undergraduate students from around the country come to Nantucket to participate in hands-on astrophysical research, supported by the National Science Foundation Research Experiences for Undergraduates (NSF-REU) program.  All of the students present their work at the winter American Astronomical Society meeting and many students contribute to peer reviewed astronomical publications.  In 2009 the MMA was awarded the nation’s highest honor in recognition of science mentoring – the Presidential Award for Excellence in Science, Engineering and Mathematics Mentoring.  Many of today’s professional astronomers have a direct or strong connection to the MMA.  I passionately support the extraordinary research and education program of the MMA and I certainly support AAVSO’s efforts to encourage amateur and budding astronomers to explore the celestial world.

Prior to my work at the MMA I was the Chief Operating Officer for the Organic Trade Association (OTA) for 15 years, the only national trade association representing the $48 billion dollar organic industry.  My responsibilities included membership, annual fund, special events, finances, and information technology.  In that role I was personally involved with all aspects of membership acquisition and retention, achieving annual fund goals, and ensuring that we produced professional national and international events.  Prior to my work at the OTA, I was the co-executive director of the Bonnyvale Environmental Education Center in southern Vermont.  I am a graduate of Yale University (MES) and the University of Massachusetts (BS).

My particular interest in AAVSO surrounds citizen science.  There is much to be gained by educating and then engaging citizen scientists in meaningful research and discovery.  And although we are all surrounded by and reliant on science in every aspect of our daily lives, science and scientists have often been dismissed either due to a lack of understanding or for political reasons (climate science, eg.).  By involving more citizens in scientific endeavors we will increase appreciation for and understanding of science.  

As a council member I hope that I might have the opportunity to assist the good and important work of the AAVSO through my love of science, education, and understanding of not-for-profit organizations.       

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Mike Joner, Provo, Utah

I was raised in southwest Washington and became interested in science and astronomy as a young boy.  My mother drove me to star parties organized by the Portland Astronomical Society, where I met other amateur astronomers.  I worked with experienced amateurs who taught me how to grind mirrors and build my own telescope.  When I was in high school, my father helped me build an observatory in our back yard.  As I moved on with my education, I continued to seek out ways to make astronomy a major part of my life.  I had always wanted to be a PhD astronomer and work as an observational researcher.  To that end, I focused on physics and astronomy in college.  I have been the resident astronomer at Brigham Young University since 1981, where I hold the rank of Research Professor in the Department of Physics and Astronomy.

My research has focused primarily on using photometric techniques to study just about anything that varies with time.  During a typical night of research at the West Mountain Observatory, targets observed can include active galaxies, transiting exoplanet candidates, globular cluster RR Lyrae stars, eclipsing binaries, SX Phe stars, recent supernovae, Cepheids, and even occasional solar system objects.  I have had opportunities to work as a visiting astronomer at major facilities all around the world.  I have spent hundreds of nights at Kitt Peak, Cerro Tololo, and the South African Astronomical Observatory.  I generally work on the modest sized meter-class telescopes, but have had the chance to spend nights working on larger telescopes such as the 4-meter on Kitt Peak or the 8-meter Gemini North telescope on Mauna Kea. One cool experience I had was to fly on the NASA Kuiper Airborne Observatory and do infrared observations.  I have even collaborated with amateur astronomers to produce educational images and secured the data for three NASA Astronomy Pictures of the Day in 2012.

My astronomy research has involved collaborations with both professional and amateur astronomers, which I find to be the most satisfying combination of research and enthusiasm.  Modern technology and the invaluable gifts of time and desire enable amateur astronomers to secure observations that are scientifically valuable.  Their passion for the subject provides me with a welcome respite from the administrative and other non-astronomical demands of my work.

I found the AAVSO early in my life but allowed raising my family, along with working and living at WMO, to put off membership until a later time.  I’m now working to make up for lost time and plan to be a part of the AAVSO as long as I’m on the planet.  These last few years of being a member of the AAVSO and attending the meetings have given me an opportunity to work in research that combines the best of scientific investigation along with a love of astronomy and the night sky.  I urge members to continue to make observations of any variable objects they choose.  My goal is to use my research background and decades of observational experience to provide assistance and suggestions that will help make the efforts of all AAVSO observers to have the maximum scientific value to other researchers throughout the astronomical community.

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*Katrien Kolenberg, Heverlee, Belgium

My fascination for the stars started when I was very young, and I am delighted to have turned this passion into a profession. I currently am an Astrophysics professor at the University of Antwerp (Belgium), while keeping professional ties with my alma mater (KU Leuven, Belgium) and the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA.  My other role is that of STEM (Science, Technology, Engineering, Mathematics) coordinator for the KU Leuven (Belgium), and thinking of ways to bring these subjects closer to young people. (And for this, astronomy is a great example, a discipline in which all the components of STEM are merged!)

 My research focuses on pulsations in different types of variables, mostly RR Lyrae stars.  I have conducted research projects combining photometric (PMT, CCD, visual, including AAVSO), spectroscopic, and spectropolarimetric data, obtained both from the ground and from space. In confronting these precious data with stellar models, we get a better understanding of the inner workings of stars. I enjoy my fruitful collaborations with amateur astronomers just as much as my involvement in current/upcoming space missions for variable stars (e.g., Kepler/K2, Gaia).  My experience across the spectrum of astronomical facilities has made me appreciate the AAVSO’s historical position and unique role all the more!

I have a strong commitment to astronomy education and outreach, particularly for communities where inspiration makes the most difference. This drives me as Steering Committee member of the International Astronomical Union’s Office of Astronomy for Development.  I have organized astronomy schools and workshops in West Africa and Central Asia for students and high-school teachers, and always point out (and teach about) variable stars as an exciting research field that is both inclusive and expansive.

As a Council member, I would like to help the AAVSO expand its membership in age range, gender, and localization (worldwide) through targeted outreach projects, as well as increase and enhance Pro-Am collaborations.

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Linda Morgan-O’Connor, Danforth, Maine

My interests are broad, including astronomy, geology, and the visual arts.  I think that having a wide variety of interests and experiences often helps me to see novel ways of looking at problems and forming creative solutions to those challenges.

My educational background includes a Bachelor’s degree in Mathematics and Natural Sciences from Worcester University.  In addition, I studied art techniques at the School of the Museum of Fine Arts in Boston, took graduate courses in Geology at the University of Connecticut, and studied Introductory Astronomy at Western New Mexico University.

I managed the Visiting Artist Studios, a component of the Explore and Discover Program of the Uxbridge Public Schools.  This program won the ASTC Award in 2001 with its partner, the Science Discovery Museum in Acton.  During my tenure there I helped to create connections between the arts and sciences, providing community and school arts and science-based exhibitions and outreach programs.  During this period I also served for several years as the President of the Blackstone Valley Art Association, managing the organization and writing grants to further the goals and projects of that non-profit organization.

Upon retirement, with time and freedom from a schedule, I was able to re-kindle my lifelong interest in astronomy.  I soon joined the AAVSO, hoping to make worthwhile observations for science.  So far, my experience has been visual observations of long-period variables, but I am looking forward to expanding my toolkit to include DSLR techniques.  Presently I am working on putting together a “road-worthy” setup for observing variables that will survive the rigors of long-term travel while not taking up very much space.  I am looking at this as my newest technical challenge.  (And trust me – I am technically challenged).

I am running for the AAVSO Council because I understand that the strongest organizations continue to grow and evolve best when many members contribute their time, energy, and unique point of view to the organization.  There is no crystal ball to predict what problems may arise for an organization during a given tenure.  I can promise to work responsibly and amicably with the group, and apply my positive energy and intelligence toward finding good solutions that will grow and strengthen our organization long into the future.

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Richard S. Post, Lexington, Massachusetts

After getting a BS in Eng. Physics from UC Berkeley, I taught physics and physics education in Bogota, Colombia, as a Peace Corps Volunteer.  Afterwards, I went to Columbia University for PhD in Applied Physics focusing on plasmas.  I was an Associate Professor in Nuclear Engineering at University of Wisconsin, Madison working in plasma physics, fusion, and plasma-material interaction.  In 1981, I moved my research to MIT, joining the Plasma Science and Fusion Center where I lead the TARA group in a large mirror confinement experiment using 24MW of utility power not available in Madison.  As fusion funding began to decline, three of us finished the experiment and started Applied Science and Technology, Inc., ASTeX, selling a product line of reactive gas generators to semiconductor equipment companies.  ASTeX went public in 1993, a time before Sarbanes-Oxley, when a small <$100M in revenue high tech equipment company could IPO.  In 2001, we merged with MKS Instruments to reduce the cost of global operations and diversify the customer base.  That year, with investors, I started NEXX Systems, this time to build semiconductor production tools focused on packaging chips for cell phones.  The iPhone created the market for NEXX’s success.  Every part in your phone was processed by ASTeX generators or packaged using NEXX System tools.  In 2012, NEXX Systems was sold to Tokyo Electron to get the infrastructure and size to support Intel and Japanese companies.  At this point, I retired.  Bought an 8” telescope and viewed my fist galaxy with my own eyes. I was hooked.  In Maine where we have a vacation home, I set up an observatory with a PlaneWave CDK17.  A few years later, I added a CDK24 in NM and one at Sierra Remote Observatories.  All are run remotely using ACP.  My focus is on the ultimate variable star – supernova - with search, photometry, and spectroscopy of bright SNs.  I work with the Puckett Supernova Search, and ASAS-SN of Ohio State University.

I joined AAVSO to learn how amateurs can produce data which can be used in professional research.  It has been a great experience for me.  I see members very committed to the organization and are all continuing to learn and seeking to expand their capability.  I would like to add my experience of 25 years as Chairman of the Board of private and public companies.  On these boards we sought to recruit board members with certain skills – finance, global operations, established contact with the customer base, and critically important, the ability to assist with funding the company.  Fast growing equipment companies like ours with 50% compound growth rates use up more cash than they can generate even when they are profitable.  I see the need for AAVSO to have similar goals for council members.  What are the skill sets required – finance, operations which includes IT, marketing, knowledge of the customer base, and the ability to help raise money? The AAVSO board should seek to find council members with these skills.  I would like to participate in this process of expanding the board skill set.  What is the purpose of a board?  One of my very successful board members told me a board is to help the CEO, approve the budget, make sure the CEO is doing a good job, and not to run the company.  His statement is a good base line for evaluating Council’s success and the contribution of each individual member.  One may think that non-profits are somehow different from for-profit companies.  However, both are social organizations which assemble for a common purpose.  They must excel in their goal or they will vanish.

I am on the AAVSOnet taskforce to provide options for the council on how AAVSOnet can continue on minimal budget and have been looking for ways that AAVSO might contribute to STEM education using AAVSOnet assets.  STEM education is an area with Stella has identified she would like AAVSO to make a contribution.

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Gregory R. Sivakoff, Edmonton, Alberta, Canada

“Space is big. You ought to find your place in it.”  Taking my Dad's advice to heart, I began researching black holes as an undergraduate in 1998, and have since earned my PhD in astronomy (2006).  In 2011, I became an Assistant Professor at the University of Alberta (Canada).  Here, I teach physics and astronomy, perform research, and heavily engage in public outreach.  I am a member of the American Astronomical Society, Canadian Astronomical Society, Royal Astronomical Society of Canada, and of course the AAVSO.

I study black holes, neutron stars, and white dwarfs, focusing on close binaries with these objects (X-ray binaries and cataclysmic variables).  I observe these highly variable objects across most of the electromagnetic spectrum, using telescopes from all over (and above) the world.  My strongest expertise is at X-ray and radio wavelengths.

I have worked with the AAVSO on observing campaigns since 2010 (e.g., working on the cataclysmic variable SS Cygni and the X-ray binary V404 Cygni).  While I started as a behind-the-scenes researcher collecting the AAVSO data, I now take it upon myself to interact closely with AAVSO members involved in a campaign.  I fully believe in the importance of citizen scientists and “professional” astronomers working together, as each community offers their own unique, and complementary set of expertise.  This cooperation was critical when AAVSO members helped my team and me determine the distance to SS Cygni.

I am honored to be considered as a potential member of the AAVSO council and it would be a privilege to serve in that position.  As a council member, I believe that I can apply the techniques I have learned through my multiple AAVSO campaigns (and in organizing the worldwide response of "professional" astronomers) to promote stronger interaction between professional and citizen scientists.  This is an especially critical time for such interaction as “professional” astronomers across the electromagnetic spectrum are reawakening to the power (and fun!) of time-domain astronomy.

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          "National Gallery" FIlm         



1909 First SOS, The first well documented use of the SOS distress call is by the Arapahoe on August 11, 1909, when it suffered a broken shaft in the Atlantic Ocean, near Cape Hatteras, North Carolina. However, an article titled "Notable Achievements of Wireless" in the September, 1910 Modern Electrics suggests that an earlier SOS distress call was transmitted by the Cunard liner Slavonia, on June 10, 1909.
[The wireless operator aboard S.S. Arapahoe, T. D. Haubner, radioed for help. A few months later, Haubner on the S.S. Arapahoe received an SOS from the SS Iroquois, the second use of SOS in America.(*TIS)]
The first radio distress call to be adopted appears to have been "CQD", by the Marconi International Marine Communication Company​, for Marconi-operated shipboard stations. It was announced on January 7, 1904 by the company's "Circular 57" that "...on and after the 1st February, 1904, the call to be given by ships in distress or in any way requiring assistance shall be 'C.Q.D.'." ("CQ" was a general call to all stations; amateur or "ham" radio operators still use it today when soliciting a contact with any station that hears the call.)

An International Radiotelegraphic Convention, ... met in Berlin in 1906. This body signed an international agreement on November 3, 1906, with an effective date of July 1, 1908. An extensive collection of Service Regulations was included to supplement the Convention, and in particular Article XVI adopted Germany's Notzeichen distress signal as the international standard, stating: "Ships in distress shall use the following signal: · · · — — — · · · repeated at brief intervals". *Citizens Compendium

In 1999, the last total eclipse of the millennium occurred. Because it traveled across many populated areas, it was perhaps the most-watched eclipse of all time, seen by possibly 350 million people. Totality occurred first over the mid-Atlantic Ocean. The first land crossed by the moon's shadow was the Isles of Scilly, then the far south-west of England, in Cornwall. Although the sun was obscured by clouds there, a dramatic darkness fell, and the temperature dropped, during the totality lasting 1-min 30-sec. From there the path of totality tracked across Europe, India and Iran. In Egypt, Muslims were ordered by clerics to shut themselves away, but Jordan and Syria declared a national holiday.*TIS 



BIRTHS

1730 Charles Bossut(11 August 1730 – 14 January 1814) was a French mathematician who was famed for his textbooks which were widely used throughout France.*SAU

1829 Norman Macleod Ferrers; (11 August 1829 – 31 January 1903) John Venn wrote of him,
.. the Master, Dr Edwin Guest, invited Ferrers, who was by far the best mathematician amongst the fellows, to supply the place. His career was thus determined for the rest of his life. For many years head mathematical lecturer, he was one of the two tutors of the college from 1865. As lecturer he was extremely successful. Besides great natural powers in mathematics, he possessed an unusual capacity for vivid exposition. He was probably the best lecturer, in his subject, in the university of his day.
It was as a mathematician that Ferrers acquired fame outside the university. He made many contributions of importance to mathematical literature. His first book was "Solutions of the Cambridge Senate House Problems, 1848 - 51". In 1861 he published a treatise on "Trilinear Co-ordinates," of which subsequent editions appeared in 1866 and 1876. One of his early memoirs was on Sylvester's development of Poinsot's representation of the motion of a rigid body about a fixed point. The paper was read before the Royal Society in 1869, and published in their Transactions. In 1871 he edited at the request of the college the "Mathematical Writings of George Green" ... Ferrers's treatise on "Spherical Harmonics," published in 1877, presented many original features. His contributions to the "Quarterly Journal of Mathematics," of which he was an editor from 1855 to 1891, were numerous ... They range over such subjects as quadriplanar co-ordinates, Lagrange's equations and hydrodynamics. In 1881 he applied himself to study Kelvin's investigation of the law of distribution of electricity in equilibrium on an uninfluenced spherical bowl. In this he made the important addition of finding the potential at any point of space in zonal harmonics (1881).

Ferrers proved the proposition by Adams that "The number of modes of partitioning (n) into (m) parts is equal to the number of modes of partitioning (n) into parts, one of which is always m, and the others (m) or less than (m). " with a graphic transformation that is named for him. *SAU

1836 Cato Maximilian Guldberg (11 August 1836 – 14 January 1902) Norwegian chemist who, with his brother-in-law Peter Waage, formulated the law of mass action (1864), which details the effects of concentration, mass, and temperature on chemical reaction rates. The law states that the rate of a chemical change depends on the concentrations of the reactants. Thus for a reaction: A + B >> C the rate of reaction is proportional to [A][B], where [A] and [B] are concentrations. In 1870 Guldberg investigated the way in which the freezing point and vapor pressure of a pure liquid are lowered by a dissolved component. In 1890 he formulated Guldberg's law which relates boiling point and critical temperature.*TIS

1842 Enrico D'Ovidio (11 Aug 1842 in Campobasso, Italy - 21 March 1933 in Turin, Italy) D'Ovidio was to work for 46 years in the University of Turin. He was chairman of the Faculty of Science in 1879-80 and rector of the University between 1880 and 1885. Another spell as chairman of the Faculty of Science between 1893 and 1907 ended when he was appointed Commissioner of the Polytechnic of Turin.
Euclidean and noneuclidean geometry were the areas of special interest to D'Ovidio. He built on the geometric ideas which had been introduced by Lobachevsky, Bolyai, Riemann and Cayley. D'Ovidio's most important work is probably his paper of 1877 The fundamental metric functions in spaces of arbitrarily many dimensions with constant curvature.
D'Ovidio also worked on binary forms, conics and quadrics. He had two famous assistants, Peano (1880-83) and Corrado Segre (1883-84). D'Ovidio and Corrado Segre built an important school of geometry at Turin. *SAU

1895 Egon Sharpe Pearson, (Hampstead, 11 August 1895 – Midhurst, 12 June 1980) was the only son of Karl Pearson, and like his father, a leading British statistician.
He went to Winchester School and Trinity College, Cambridge, and succeeded his father as professor of statistics at University College London and as editor of the journal Biometrika.
Pearson is best known for development of the Neyman-Pearson lemma of statistical hypothesis testing.
He was President of the Royal Statistical Society in 1955–56, and was awarded its Guy Medal in Gold in 1955. He was awarded a CBE in 1946.
He was elected a Fellow of the Royal Society in Mar 1966. His candidacy citation read: "Known throughout the world as co-author of the Neyman-Pearson theory of testing statistical hypotheses, and responsible for many important contributions to problems of statistical inference and methodology, especially in the development and use of the likelihood ratio criterion. Has played a leading role in furthering the applications of statistical methods - for example, in industry, and also during and since the war, in the assessment and testing of weapons." *Wik

1912 Norman Levinson (August 11, 1912, Lynn, Massachusetts – October 10, 1975, Boston) set out to become an electrical engineer. Here he describes the events that led to his change of major:
I became acquainted with Wiener in September 1933, while still a student of electrical engineering, when I enrolled in his graduate course. It was at that time really a seminar course. At that level he was a most stimulating teacher. He would actually carry on his research at the blackboard. As soon as I displayed a slight comprehension of what he was doing, he handed me the manuscript of Paley-Wiener for revision. I found a gap in a proof and proved a lemma to set it right. Wiener thereupon sat down at his typewriter, typed my lemma, affixed my name and sent it off to a journal. A prominent professor does not often act as secretary for a young student. He convinced me to change my course from electrical engineering to mathematics.
Some of his major contributions were in the study of Fourier transforms, complex analysis, non-linear differential equations, number theory, and signal processing. He worked closely with Norbert Wiener in his early career. He joined the faculty of the Massachusetts Institute of Technology in 1937. In 1954, he was awarded the Bôcher Memorial Prize of the American Mathematical Society. In 1974 he published a paper proving that more than a third of the zeros of the Riemann zeta function lie on the critical line, a result later improved to two fifths by Conrey.*SAU

1921 Tom Kilburn (11 August 1921 – 17 January 2001) British electrical engineer who wrote the computer program used to test the first stored-program computer, the Small-Scale Experimental Machine, SSEM, also known as "The Baby." First tested on 21 Jun 1948, the program took 52 minutes to run. The tiny experimental computer had no keyboard or printer, but it successfully tested a memory system developed at Manchester University in England. This system, based on a cathode-ray tube, was the first that could store programs, whereas previous electronic computers had to be rewired to execute each new problem.*TIS

1950 Steve Wozniak, (August 11, 1950; ) Apple inventor, is born
Wozniak and Jobs entered into business after Wozniak designed a single-board personal computer known as the Apple I. In 1976, with specifications in hand and an order for 100 machines at $500 each from the Byte Shop, he and Jobs founded the business.
While still studying at the University of California-Berkeley in 1972, Wozniak had shown his electronics skill as well as his sense of humor in building his blue box, a tone generator used to make free phone calls, which he sold in dormitories
Wozniak now teaches computer science to school children in his home town of Los Gatos, California. *CHM

1956 Pierre-Louis Lions (August 11, 1956, ) French mathematician who was awarded the Fields Medal in 1994 for his work since the 1980's on partial differential equations. The sources of such equations are many - for example, physical, probabilistic or geometric and other diverse subareas - each studying different phenomena for different nonlinear partial differential equations by utterly different methods. Pierre-Louis Lions has been called unique in his ability to transcend these boundaries and to solve pressing problems throughout the field.*TIS



DEATHS

1464 Nicholas von Cusa died (1401 – August 11, 1464). We know his work in mathematics primarily because a home for the aged in Kues, which he generously endowed, has survived the ravages of time and war. Luckily his own manuscripts were housed there.*VFR
Nicholas is also considered by many to be a genius ahead of his time in the field of science. Nicolaus Copernicus, Galileo Galilei and Giordano Bruno were all aware of the writings of Cusanus as was Johannes Kepler (who called Cusanus 'divinely inspired' in the first paragraph of his first published work). Predating Kepler, Cusanus said that no perfect circle can exist in the universe (opposing the Aristotelean model, and also Copernicus' later assumption of circular orbits), thus opening the possibility for Kepler's model featuring elliptical orbits of the planets around the Sun. He also influenced Giordano Bruno by denying the finiteness of the universe and the Earth's exceptional position in it (being not the center of the universe, and in that regard equal in rank with the other stars). He was not, however, describing a scientifically verifiable theory of the universe: his beliefs (which proved uncannily accurate) were based almost entirely on his own personal numerological calculations and metaphysics.
Cusanus made important contributions to the field of mathematics by developing the concepts of the infinitesimal and of relative motion. He was the first to use concave lenses to correct myopia. His writings were essential for Leibniz's discovery of calculus as well as Cantor's later work on infinity. *Wik

1578 Pedro Nunes or Nunez (1502 – August 11, 1578) was a Portuguese scholar who worked in geometry, spherical trigonometry, algebra as well as geography, physics, and cosmology. *SAU He was the first to propose the idea of a loxodrome and was also the inventor of several measuring devices, including the nonius, named after his Latin surname. *Wik

1854 Macedonio Melloni, (11 April 1798 – 11 August 1854) Italian physicist who was the first to extensively research infrared radiation. Sir William Frederick Herschel discovered infrared radiation in 1800, but research stalled until the invention of a thermopile in 1830. That instrument was a series of strips of two different metals that produced electric current when one end was heated. Melloni improved the thermopile and used it to detect infrared radiation. In 1846, from an observation point high on Mount Vesuvius, he measured the slight heating effect of moonlight. He showed also that rock salt, being transparent to infrared, made suitable lenses and prisms to demonstrate the reflection, refraction, polarization and interference of infrared in the same manner as visible light.*TIS

1892 Enrico Betti (21 October 1823 – 11 August 1892) was an Italian mathematician, now remembered mostly for his 1871 paper on topology that led to the later naming after him of the Betti numbers. He worked also on the theory of equations, giving early expositions of Galois theory. He also discovered Betti's theorem, a result in the theory of elasticity. *Wik

1955 Robert Williams Wood (May 2, 1868 – August 11, 1955) was an American experimental physicist. He photographed the reflection of sound waves in air, and investigated the physiological effects of high-frequency sound waves. The zone plate he devised could replace the objective lens of a telescope. He invented an improved diffraction grating, did research in spectroscopy, and extended the technique of Raman spectroscopy (a method to study matter using the light scattered by it.) He made photographs showing both infrared and ultraviolet radiation and was the first to photograph ultraviolet fluorescence. Wood was the first to observe the phenomenon of field emission in which charged particles are emitted from conductors in an electric field. *TIS
According to a post at Greg Ross' Futility Closet:
"How to clean a 40-foot spectrograph, from R.W. Wood’s Researches in Physical Optics, 1913:
The long tube was made by nailing eight-inch boards together, and was painted black on the inside. Some trouble was given by spiders, which built their webs at intervals along the tube, a difficulty which I surmounted by sending our pussy-cat through it, subsequently destroying the spiders with poisonous fumes.
This was the least of Wood’s exploits. Walter Bruno Gratzer, in Eurekas and Euphorias, writes that the physicist “would alarm the citizens of Baltimore by spitting into puddles on wet days, while surreptitiously dropping in a lump of metallic sodium, which would explode in a jet of yellow flame.”

1977 Sir Frederic Williams, (26 June 1911 Stockport – 11 August 1977 Manchester) British electrical and electronics engineer who, with Tom Kilburn, invented the Williams tube, a cathode-ray tube using the persistence of the image on the phosphor screen for data storage. This made possible the random access memory that launched the digital computer age. As the Chair in Electrotechnics at Manchester University, he incorporated this invention into the Mark I computer, the world's first stored-program digital electronic computer to be commercially produced during the early 1950's. *TIS

1995 Alonzo Church (June 14, 1903 – August 11, 1995) made important contributions to mathematical logic and theoretical computer science.*SAU He is best known for the lambda calculus, Church–Turing thesis, proving the undecidability of the Entscheidungsproblem, Frege–Church ontology, and the Church–Rosser theorem. *Wik

2003 Armand Borel (21 May 1923 –11 August 2003) was a Swiss mathematician, born in La Chaux-de-Fonds, and was a permanent professor at the Institute for Advanced Study in Princeton, New Jersey, United States from 1957 to 1993. He worked in algebraic topology, in the theory of Lie groups, and was one of the creators of the contemporary theory of linear algebraic groups. *Wik



Credits :
*CHM=Computer History Museum
*FFF=Kane, Famous First Facts
*NSEC= NASA Solar Eclipse Calendar
*RMAT= The Renaissance Mathematicus, Thony Christie
*SAU=St Andrews Univ. Math History
*TIA = Today in Astronomy
*TIS= Today in Science History
*VFR = V Frederick Rickey, USMA
*Wik = Wikipedia
*WM = Women of Mathematics, Grinstein & Campbell
                  



On October 21, 1897 the Yerkes Observatory in Williams Bay, Wisconsin was dedicated in a 4-day conference that included the 4th annual gathering of board members of the Astrophysical Journal.  See a list below of the sixty or so people who gave lectures and demonstration, or simply attended.  It is fun to note that many of the attendees slept at the observatory during the conference, sleeping on cots borrowed from the YMCA.  The village of Williams Bay had a boarding house to accommodate
The president of the university and benefactor Charles
Yerkes were also on hand to present and accept recognition.
The Yerkes remains as the largest refracting telescope ever built and the Observatory is still in operation, recognized for its stellar motion research and cartography.  In 1944 it was at Yerkes that Gerald Kuiper discovered an atmosphere over Titan, Saturn's satellite 



The Yerkes observatory captured the Lunar impact crater, Theophilus  with the 40-inch refracting telescope at Yerkes Observatory.  The crater is 14,000 feet deep and 62 miles in diameter.
 
Early equipment at the observatory included a double-slide plate carrier photographic accessory for the 40-inch refractory telescope.
 




A 24" reflecting telescope
was used in the south east dome at the Yerkes Observatory in 1897.  The mirror was made by Mr. Ritchey who would in 1905 leave Yerkes and head to the Mt. Wilson observatory with George Hale. 





 
To the original Bruce spectrograph was added the Rumford spectroheliograph.  George Hale's work with spectrographhelioscopes furthered investigations of the sun and resulted in the first ever photos of red stars (aka Secchi's fourth type).  One of the earliest spectroscopes made for the 40-inch Yerkes telescope, and exhibited at the Columbian Exposition, was built by John Brashear.
 

40-inch refractor Yerkes telescope, built by Warner and Swasey of Cleveland, Ohio.  It originally appeared in the 1893 Columbian World's Fair Exposition in Chicago, without a lens.  A lens had been cast by Alvan Clark for another observatory but the benefactor backed out, owing Clark $16,000.  That meant the 42-inch casts were available to be cut for another telescope.  George Hale, hired by the University of Chicago to build an observatory for the school, recognized that building a telescope to match the lense would result in the largest telescope in the world - exactly the kind of attention-getting project apt to appeal to a prospective benefactor, Charles T. Yerkes.


Yerkes 40 inch telescope at 1893 Worlds Fair in ChicagoAt the fair, the telescope was installed at the north end of the mail aisle in the north gallery of the Manufactures and Liberal Arts building. One of several fires after the fair threatened the telescope but it was saved and installed at the Yerkes observatory in time for the 1897 dedication ceremonies.

For eleven years, 1897 to 1908, it was the world's largest telescope.  Mt. Wilson's 60-inch instrument took that title away in 1908, followed a decade later by a Wilson's 100-inch telescope.


George E. Hale (1868-1938), founder of Yerkes

Observatory was the son of a wealthy Chicago elevator manufacturer, William E. Hale, George Hale was passionate about astronomy.  His passion, backed by his father's money, had good results for astrophysics.

A Chicago native, George Ellery Hale attended MIT, Harvard and the Humboldt University of Berlin, but did not graduate.  Instead he returned to Chicago and persuaded his father to purchase a used 12-inch Alvan Clark telescope and build an observatory in the family's back yard to put it in.  The Hales lived on Drexel Avenue in Chicago's affluent Kenwood neighborhood so an observation dome must have been an unusual sight. 

At his new Kenwood Observatory, Hale continued work he'd begun at MIT on a spectroheliograph with which to photograph the sun.  His success and enthusiasm earned sufficient respect from people working in the field that William Rainey Harper -- first president at the University of Chicago, appointed by John D. Rockefeller who donated the money to start the university in 1890 -- was willing to overlook deficiencies in George's academic accreditation to bring him onto the faculty.  George's father and Harper struck a deal. 



The Hales would donate the equipment at Kenwood to the university in exchange for George being named an associate professor of astrophysics, and being named director of a yet to be constructed observatory for which the university would raise at least $250,000.  Hale and Harper persuaded Charles T. Herkes to put up $300,000 by flattering him with the prospect of having his name on the facility with the world's largest telescope, then leaking word to the press about the large donation, making it difficult for Yerkes to back out without earning bad publicity.  Yerkes was in the midst of acquiring access contracts for an elaborate railway project (see below) and it was a bad time for negative publicity so the University got the necessary funds.  As a faculty member, George Hale had just one job: build an observatory for the University of Chicago.

For Hale, Yerkes was a stepping stone to gain access to even higher capacity instruments.  In 1905, his job at Yerkes done, he left U of C to join Carnegie Institute where a 60-inch refractory telescope was in progress at the Pasadena-based Mt. Wilson Solar Observatory.


Charles T. Yerkes
Had the Yerkes project been delayed, it might not have been built.  Three years after the dedication ceremony, its patron, Charles Tyson Yerkes (1837-1905), left Chicago in a huff after losing a battle with the Chicago city council and mayor, Carter Harrison Jr.  Yerkes had acquired and consolidated numerous elevated railway companies to build an elevated railway loop around Chicago's downtown commercial area (The Loop), dramatically expanding the city's mass transit capacity.  He then bribed state legislators to pass a law giving municipalities the right to grant long-term franchises. His franchise application was rejected by the Chicago city council, however, when alderman heard that for the next 50 years, Yerkes was to get a commission on every fare sold that traveled on the Loop. 
Yerkes also donated an electric water fountain to Chicago that was featured during the Columbian exposition.

American author,  Theodore Dreiser, based a series of novels on Yerkes, called the Cowperwood trilogy.  During his years in Chicago, Yerkes became an avid art collector.  Not all of his selections were as well researched as they might have been.  For example, one painting that Yerke attributed to Hans the Younger, English Tudor King Henry VIII's favorite painter, was dated 1575 -- thirty two years after the artist's death.  Shown below: The Fool, attributed by Yerkes to Hans Holbein the elder

The historic meeting between George Hale, William Harper and Charles Yerkes that resulted in Yerkes agreeing to fund the observatory took place October 4, 1892.











Dedication of the Yerkes Observatory in October, 1897 was made part of a 4-day conference that included the 4th annual gathering of board members of the Astrophysical Journal.  Following is a list of attendees and session topics. 

  • "Application of Diffraction Phenomena to Astronomical and Astrophysical Measurements"
  • "Electric Radiation," "Source of Characteristic Spectrum of the Metallic Arc"
  • "Effect of Pressure on Wave length"
  • "Spectra of Stars on Secchi's Third Type"
  • "Researches in Stellar Spectrography"
  • "Oxygen in the Sun"
  • "Great Nebula of Orion"
  • "Jovian Phenomena"
  • "The System of Beta Lyrae"
  • "The Teaching of Theoretical Astronomy in America"
  • "Jacobi's Investigations in Theoretical Astronomy"

The 40-inch telescope played an important role in the conference with display of chromosphere and prominences, the reversal of the H and K lines in prominences and faculae and the duplication of the D3 line.  There were also demonstrations showing the grinding of a five-ft speculum and an exhibition on testing mirror, parallel plates, and attendees were able to look in on the progress of other Yerkes equipment under development, including a 24-inch heliostat and coelostat, an equatorial mounting for a 24-inch reflector telescope, a spectroheliograph for the 40-inch telescope and a ruling machine for optical gratings, as well as how-to's on making a perfect straight edge and grinding a perfect screw.

Delivering addresses and In attendance:

  • Dr. John Brashear
  • F. L. O. Wadsworth (Yerkes astrophysicist professor)
  • Dr. G. F. Hull (Colby University professor of physics)
  • Dr. Henry Crew (Northwestern University physics professor)
  • Dr. Henri Deslandres (Paris observatory astrophysicist)
  • Dr. W. J. Humphreys (University of Virginia)
  • James E. Keeler (Allegheny Observatory professor)
  • H. C. Lord (Emerson McMillin Observatory Ohio State University professor)
  • Carl Runge (director Spectroscopic Laboratory, Technische Hochschule, Hanover)
  • Ormond Stone (director Leander McCormick Observatory University of Virginia)
  • George C. Comstock (Washburn Observatory University of Wisconsin)
  • C. L. Doolittle (Flower Observatory University of Pennsylvania)
  • Father Hedrick (Georgetown College Observatory)
  • H. S. Pritchett (Washington University observatory director)
  • Dr. Charles L. Poor (assoc. professor astronomy John Hopkins university)
  • J. K. Rees (Columbia University Observatory director)
  • E. E. Barnard (Yerkes astronomy professor)
  • Father Hagen (Georgetown Observatory)
  • G. W. Hough, Dearborn Observatory)
  • G. W. Myers (University of Illinois Observatory)
  • Simon Newcom, E. C. Pickering (Harvard Observatory)
  • D. Kurt Laves (University of Chicago)
  • Mary Whitney (Vassar Observatory)
  • J. A. Parkhurst (Marengo, IL)
  • O. H. Basquin (Evanston, IL)
  • Miss Cunningham (Swarthmore Observatory)
  • A. S. Flint (Washburn Observatory)
  • F. R. Moulton (University of Chicago)
  • A. A. Michelson (physics professor University of Chicago)
  • Miss Furness (Vassar)
  • E. F. Nichols (Colgate University)
  • Professor Upton (Ladd Observatory Brown University)
  • Professor Van Vlack (mathematics and astronomy professor, Wesleyan University)
  • Professor Malcome McNeil (Lake Forest University)
  • Edwin F. Sawyer (brighton, Mass)
  • F. H. Scares (University of California)
  • Father Searle (Catholic University at Washington)
  • G. M. Hobbs (Ryerson Laboratory University of Chicago)
  • Dr. S. D. Townley (Detroit Observatory, University of Michigan)
  • William Harness (professor US Naval Observatory and superintendent of Nautical Almanac)
  • W. W. Payne (professor director Goodsell Observatory)
  • E. B. Frost (director Shattuck Observatory Dartmouth)
  • Professor Snyder (Philadelphia Observatory)
  • Professor Stockwell (Cleveland)
  • Professor McLeod (McGill University of Montreal)
  • Rev. A. W. Quimby (Berwyn, PA)
  • Reginald Fessenden (professor physics Western University Pennsylvania)
  • E. L. Nichols (physics professor Cornell)
  • Professor Leavenworth (director University of Minnesota Observatory)
  • Professor Paul (US naval observatory of Washington)
  • Professor Pupin (physics Columbia University)
  • C. A. Becon (director Smith Observatory at Beloit College)
  • William H. Collins (director Haverford College Observatory)
  • Charles Rockwell (Tarrytown, NY)
  • Dr. Tatnall (physics professor University of Pennsylvania)
  • Mr. Brooks (director Geneva, NY observatory)
  • Frank W. Very (Ladd Observatory, Brown)
  • E. D. Eaton (Beloit College)
  • Winslow Upton (Brown University)
  • N. E. Bennett (Wilmington College)
  • C. K. Adams (University of Wisconsin)
  • W. P. Lackland (Illinois Wesleyan University)
  • General Schofield (Wisconsin)
  • Charlie Schaefer (State University of Iowa)
~~~~~~~~~~~~~~

Set of 6 fridge magnets featuring the early years of Yerkes Observatory.


Additional reading

          Nova Centauri 2013: a crucial 24 hours        
My long-suffering wife is clearly bemused why I keep getting up at 3.00 am to "go and look at the nova".  So I thought I'd try to explain some of the excitement.

I posted in some depth about the nova here.  So the short version is simply that a small, incredibly dense star -a white dwarf - has staged a gigantic runaway thermonuclear explosion, blasting clouds of hydrogen and other elements into space at incredible speed, while pumping enormous energies at visible wavelengths, X-ray and gamma ray wavelengths.  This started last Tuesday, nearly a week ago.  On Saturday it reached its peak brightness, and it's now fading fast.

This star is quite close to the top pointer to the Southern Cross - so invisible to most (Northern hemisphere) variable star enthusiasts.  The upshot is, I and a handful of Australian, New Zealand, South African and South American observers have been hauling ourselves out of bed to measure and observe the thing. 

A few of us have rudimentary spectroscopes - devices that can spread the white light of the star into its constituent spectrum. It's a simple filter which screws into the front of the camera.  With this one can measure the intensity of each wavelength of light, from deep violet into the red and infra-red.  You can see this at the bottom of the photo below:


The graphs simply plot the intensity of each wavelength of light.

So what does this tell us?  The key to the whole process is to understand that, for some fascinating quantum-physical reasons, particular elements radiate and absorb light at particular wavelengths.  For instance if hydrogen is heated or bombarded with ultraviolet or otherwise energised, it will radiate light at a very specific set of wavelengths - 4861 angstroms, (in the light blue part of the spectrum);  6562 angstroms (in the red zone); and others.  Other elements emit light at different wavelengths.  So, by analysing the spectra of glowing clouds of gas, we can work out their chemical compositon.

The same effect works in reverse.  If a cloud of cool hydrogen is in between us and a bright light source (like an exploding white dwarf star), the gas will absorb light at the same wavelengths.  This also applies to other elements and compounds.  For instance, the big dip in the far right of the spectra above, labelled "Telluric", has nothing to do with the nova: these are the wavelengths absorbed by the water vapour and oxygen in the Earth's atmosphere.

The red line in the graph above shows the nova's spectrum when it was at its brightest, on 6 December.  The red line is the spectrum a day later.  An awful lot has changed; as you'd expect given that the star is in the process of exploding. 

First, and perhaps least interesting - we can see what sort of elements the star is flinging into space.  This particular nova is a "Helium-Nitrogen" nova; slightly less common than the "Iron" novae.  We can tell because we see particular wavelengths glowing that correspond to ions of these elements.  Uninteresting - but it's pretty cool that I can measure the chemical composition of an exploding star 25,000 light years away from the comfort of my own balcony in Canberra. 

Next, we can build a picture of exactly what's happening to the star through comparing successive spectra.  First, let's visualize the explosion.  A cloud of gas has been blasted away from the surface of the star, and this cloud is then being bombarded by high energy waves from the star, casing the gas to glow.






This is a photo the Hubble Space Telescope took of a nova that exploded in 1992.  The ejected gas has expanded to the point where we can actually see it.  In the current nova in  Centaurus, the gas is far too close to the star for us to see it.  But we can observe it with our spectrographs.

As you can see, the gas is moving away from the star, and glowing owing to the intense energies it is being bombarded with,  This causes "emission lines"in the spectra.  You can see in my spectra from 7 December (the blue line in the graph) that the hydrogen line at 6562 A has begun to glow much more than was the case even 24 hours before (the red line in the graph). This accounts for the peaks in the spectra - the energetic gas expanding outwards from the central star.

But remember that elements also absorb energy.  Part of the expanding, glowing sphere of gas is coming straight towards us, and being "backlit" by the intense energy of the star itself.  In this case, the high-intensity light from the star itself is actually absorbed by the expanding gas cloud.

Now here's the best bit.  In the circled part of the red graph, you can see both the emission lines from the expanding cloud of hydrogen (the peak), and the absorption line that comes from the part of the cloud directly between us and the star, attenuating its energy (the trough).   These are at exactly the same wavelength - 6562 Angstrom.  But hang on - if both the emission and the absorption are at the same wavelength, why don't they just cancel each other out?

The answer is is the Doppler effect.  The emission lines come from the gas that is moving out at a right angle to us - so is neither getting closer nor further away.  But the absorption line comes from the gas coming directly towards us, so the emission line appears bluer than it is, because the energy of the velocity at which the gas is moving towards us is added to the energy of the light waves.  It's the same principle that causes the engine tone of a car moving towards us sounds higher, while a car moving away sounds lower.

By measuring the shift between the emission lines and the absorption lines, we can calculate how fast the gas is moving towards us.  The emission line is at 6562, while the absorption line is at about 6505.  6505/6562 = 0.99131.  Thus, the gas is moving towards us at 1-0.99131 = 0.00868 times the speed of light.  The speed of light is 299 792 458 m/s, so the velocity of the expanding gas cloud is 299 792 458 * 0.00868 = 2,604 km/s.  Which is about right for this type of nova; but bloody fast if you think about it.

          Carnegie shows its stuff at USA Science & Engineering Festival        
 

Do you know how a diamond is formed? Can you name one of the craters of Mercury? Have you ever held a fossilized shark tooth?

For anyone who stopped by the Carnegie booth at the USA Science & Engineering Festival this weekend, the answer to all of those questions would be a resounding “yes!”

More than 40 volunteers from four departments, including scientists, Carnegie Academy for Science Education educators, and administrative staff, welcomed thousands of the estimated 350,000 Festival visitors to our booth with a range of fun, interactive science. Some volunteers even brought their families along to lend a hand!

“Thank you so much to everyone at Carnegie who came out and volunteered their time and their knowledge to help make our booth one of the best at the Fest,” said Dione Rossiter, Carnegie’s Scientific Programs & Outreach Manager, who planned and organized the booth’s schedule, activities, giveaways, and appearance.

Some scientists, such as the Geophysical Lab's Dan Hummer, and Plant Biology's Cindy Ast, brought their own educational materials. Dan filled a blacklight box with his personal supply of fluorescing minerals and Cindy brought a homemade tool that uses a tiny lens and a light to turn a smartphone into a microscope for studying leaves and flower petals up close.

Other scientists, such as Steve Shirey and Alycia Weinberger of the Department of Terrestrial Magnetism shared their expertise with activities that have long been favorites of Carnegie's education and outreach teams. Shirey supplied a box of raw diamonds and garnets that could be studied under microscopes—popular with the parents as well as the kids. Alycia brought her supplies for making homemade spectrographs and a range of lightbulbs, the light from which looks basically the same to the naked eye, but very different using one of her nifty, handheld tools.

Fossilized shark teeth, donated by the Geophysical Lab’s Bob Hazen, were especially in demand, as kids got to sift through boxes of sand looking for treasure to take home.

Julie Edmonds’ CASE team brought some of their favorite activities for teaching kids about Mercury and the MESSENGER spacecraft that orbited it for four years, including a floor puzzle and cards explaining the different types of craters found on the planet’s surface. And the events team offered the spinning Giant Magellan Telescope hologram, which was so cool it got highlighted by the Festival’s own outreach team on social media.

And right next door, Embryology’s Steve Farber and his bioEYES gave kids a look at different stages of zebrafish development, from egg to adult, with new babies on display every day.

“Outreach efforts like this are crucial for communicating the scope of our research at Carnegie to the general public, as well as the importance and excitement of discovery science—both of which are high institutional priorities,” said President Matthew Scott.

Department breakdown at the booths:

  • BioEYES: 6 volunteers
  • CASE: 4 volunteers
  • DTM: 10 volunteers
  • Embryology/JHU: 11 volunteers
  • GL: 16 volunteers
  • PB: 1 volunteer, Cindy Ast, who gets the farthest traveled award!
  • P St: 6 volunteers
Scientific Area: 

          The Smallest Star        

Cory McAbee is one of my favorite artists. I mistakenly discovered his work when I watched Stingray Sam on Netflix thinking it was a 50s western. It was not. His story is incredible. His work is weird and wild and free. So I'm really very excited that he's bringing his latest show, The Small Star Seminar, to Atlanta on March 2. It's the story of a traveling salesman/motivational speaker who motivates people to stop improving themselves in the name of science. Each city will be filmed and edited together to create a documentary of the event. 

I got to thinking about the story of this speaker and what might have motivated him to begin his travels and this is what came out. I hope it is in keeping with the spirit of the performance.
----------------------------------------------------------------------------------------------------
Before the door opened he composed himself. The smile, seemingly painted on, stretched almost literally from ear to ear. The suit, while a little shabby, fit like a dream. Nevermind the bit of dust on his shoulders. The stance, if not off-putting, was solid. Two feet on the ground, knees bent, hips turned. It was a solid looking pose. The kind of pose a man wore when he was about to make the sale of his life. The door opened.

"May I help--"

"Hello, ma'am. I'm here today representing Minuscule Moon Visual Enhancements and I have singularly the most important purchase of your year with me here this very day."

From seemingly nowhere he presented a red telescope, held in both hands, as evidence. His grin never wavered, somehow remaining in place even while he was speaking. The pitch continued as the door creaked on its hinges, beginning its slow closing journey. It took a turn then, the pitch, and as he sang the door stopped its closing. She kept it open. Only an inch, but it was still open.

"Have you ever sat in your yard and wondered,
or even blundered,
in your mind for the wonder of all of this?"

To make his point the salesman gestured towards the sky in lax fashion, his smile only outdone by the twinkle of faint stars in waning daylight.

"With a little help from me
you can simply see
that all those spots are sawdust flying by.
Telescopic visions for you
allow your eyes to see true
all those beautiful and wonderful stars inside your sky!"

The door didn't budge. She wasn't sure if she should clap or not. It seemed a good song but, really, she just needed to get back to dinner.

He continued the pitch, now without song. "All this for on $49.95, or two payments of $24.95. Or, we have a family pack for all the many Minuscule Moon mariners in your house. If you'll--"

It was unclear if the sounds he heard were echoes or if she was, very quietly and politely, saying something about how she needed to return to her meal and her family. In any case the door shut with a whooshing sound and he stood perfectly still, red telescope still in his hands. A dog barked from inside. Dusk was quiet then, painfully so, and he wished for nothing more than to try his pitch at another home where they would receive the gifts he brought with tremendous praise. "Oh, thank you!" they'd say. "You can't imagine how often we'd wondered at the wonder of the night sky, curious as to how we might ever unlock its visual splendor. You are truly here in the nick of time!"

Alas, it was half past six and they were eating chicken and watching the news.

And so he walked for a time, brogues clacking nobly on the sidewalk, and he entered the first door his shape darkened. The suitcase that held his telescopes and a second black suit, identical to the one currently on his person, fit snugly between the bar and the stool. There was gratitude, somewhere in his subconscious, for the sturdy seat. He couldn't stand wobbly stools. They drove him mad.

The little bar was quiet and dim. He liked the steady murmur of voices and the moan of the cowboy on the radio, the little hills and valleys they produced in his mind. When the bartender finally stood before him he asked for a glass of red wine and wondered why the tall, thin person reminded him of a rabbit. Must have been the pronounced front teeth and deep, tired eyes.

Halfway through the cheap glass something caught his eye. It broke through the ceaseless thought-stream of starscapes and tunes and empty checkbooks. It was a newspaper. Well, it wasn't the newspaper but an image printed on the newspaper. That of a star, bright white against black ink. It shone with a light of its own, seemingly, and he sent his hand to snatch it off the bar.

Neither heads nor tails could be made of the ad (he assumed it was an advertisement because there was an address at the bottom), but on it were fascinating line drawings, figures of humans exploring some branch of the omniverse with hope. Written on it were exciting words like "astroneurology" and "neurostronomer", as in "Are you a neurostronomer? Would you like to be?"

Yes, he thought, yes I would!

The glass was left unattended, still half full, with a five dollar bill nestled underfoot (the wine was listed as $6 on the menu but he probably hadn't read it). His shoes clacked harder this time as he walked with purpose, hoping to reach the place before it closed. Surely it had already but there was always a chance, the smallest of chances, that they (whoever they might be) were there waiting for him. It surprised him to realize that the storefront was a scant five blocks away, which he covered in a matter of minutes. He didn't mind the sweat; his undershirt already smelled a little bit but his deodorant masked it well. His heart skipped when he thought he'd passed it but he hadn't. Turning to his right put a door before him, black and smooth. A star was mounted over the door, the very same star that had been printed on what he had presumed and hoped to be a hiring ad.

There were no lights, no windows for the lights to shine through, no 'Open' or 'Closed' sign. But he tried the door and it opened.

Inside the door was darkness like pitch. "Hello?" he shouted, but the sound fell flat as if crashing into a soft mattress.  He wasn't afraid. He checked but there wasn't any fear, just anticipation, so he stepped in.

Instantaneously, when his foot hit the tile, white lights flicked on in a line on the floor. The little rays led him to a second doorway, dark as the rest of the odd space but with a faint glow coming from the wall. It was a screen casting dead black. Slowly, resolutely, gentle music began to pipe in from unseen speakers. On the screen appeared another star with a shape below it, that of a skeleton mermaid forming a crescent. The image faded away to neon purples and and greens and when those faded away words appeared on the screen matching those sung by a disembodied voice.

"Out of the mud grows the lotus.
Be the mud and let the future shine!
It will never be your time."

He smiled and sat on the floor. The lovely voice continued.

"Pressure creates the diamond.
Be free of the pressure in your mind!
It will never be your time."

I like this song, he thought.

"Be free of possibility.
You'll see that everything is fine!
It will never be your time."

Heeding the suggestion of the song he felt himself drift away. With him went expectation and station, position and wealth. Before he could go away completely, swimming out of the music, a voice spoke up as the screen yet again shifted images. Now were more purples and greens in spectrographic lines that followed the new voice.

"Welcome to the Small Star Corporation!" said the voice. It could not be described as anything but restful. It was neither masculine nor feminine, gentle nor harsh. It was rest given speech. "We are so pleased to see you. Thank you for responding to our inquiry."

"You're welcome," he said.

"Here at the Small Star Corporation, we don't believe in reaching for the stars. What are stars anyway? Has anyone ever even reached those things? We doubt it. And why does anybody really care about that shit? Success. Authority. It's a lot of work for a lot of trouble. Think about it."

"I will," he said.

"Here at the Small Star Corporation we are much more interested in reaching for the stars...in your mind. Everything you need is right there within the magical synapses and pathways and cells and electromagnetism that is your brain. It's science. No more looking for anomalous acceptances and praise out there in the cold, heartless world. It's all up there. What's more, we believe in extending this belief to others and we are looking for a gifted few who will take the message to the masses."

After that came an explanation, more information than he needed for he was sold from the get-go. No benefits package was needed, no per diem required. It didn't matter that he hadn't met an actual person. The important thing was the message. He would recall every word, and he did. He began the next day by walking to the airport and leaving his old life behind. No longer would he peddle telescopes and false dreams of astronomical flimflam. He didn't bother informing Minuscule Moon Visual Enhancements of his decision. From now on, he was selling hope for the Small Star Corporation.

          Participation in Student Solar Spectrograph Competition        
none
          Opening a Wider Window on the Universe        

An innovative astronomical spectrograph (WIFIS) has achieved “first light.” It was developed by a team including U of Toronto and Dunlap astronomers,

The post Opening a Wider Window on the Universe appeared first on Dunlap Institute.


           MEASUREMENT OF THE INSTRUMENTAL RESPONSE FUNCTION OF THE MOUNT-STROMLO COUDE ECHELLE SPECTROGRAPH         
CRAWFORD, IA; REES, PCT; DIEGO, F; (1987) MEASUREMENT OF THE INSTRUMENTAL RESPONSE FUNCTION OF THE MOUNT-STROMLO COUDE ECHELLE SPECTROGRAPH. OBSERVATORY , 107 (1079) pp. 147-153.
           Preliminary Engineering Design and Cost Estimate for a Moderate Resolution Imaging Spectrograph for the Keck Telescope         
Charalambous, A; Walker, DD; (1987) Preliminary Engineering Design and Cost Estimate for a Moderate Resolution Imaging Spectrograph for the Keck Telescope. (Report of design study commissioned by Caltech , pp. pp. 1-77 ).
           Overall Philosophy of the Echelle Spectrographs for the Anglo-Australian Telescope and William Herschel Telescope         
Walker, D; (1987) Overall Philosophy of the Echelle Spectrographs for the Anglo-Australian Telescope and William Herschel Telescope. (Instrumentation for Ground-Based Optical Astronomy, Present and Future , pp. 21-XX ).
          DESI, le coup d’envoi est donné !        
L’instrument Desi (Dark Energy Spectroscopic Instrument) analysera la lumière émise par 35 millions de galaxies et quasars à plusieurs moments du passé de l’Univers et jusqu’à 11 milliards d’année, pour mieux cerner l’énergie noire. Son passage en phase de construction en 2016 couronne plusieurs années de recherche et développement qui ont abouti à un design solide et une stratégie d’observation crédible. L’Irfu, partenaire du projet depuis la première heure, y a tenu toute sa place. Retour sur une année qui a vu le projet devenir réalité. Une nouvelle phase commence pour DESI La phase de construction de DESI a été lancée l’été dernier après approbation par le département de l’énergie américain (DOE). Son installation auprès du télescope Mayall de 4 m (Fig. 1) situé à l’observatoire national Kitt Peak en Arizona commencera en 2018 avec l’arrivée du correcteur de champ.   La campagne d’observations, portant sur un tiers du ciel, débutera en 2019 et durera 5 ans. Elle devrait produire 10 fois plus de données que le projet précédent, BOSS (Baryon Oscillation Spectroscopic Survey) achevé il y a deux ans. Cette dernière phase d’approbation par le DOE permet de lancer la construction des pièces maîtresses de l’instrument. A savoir, les 5000 robots positionneurs de fibres (Fig. 2) qui permettront de pointer précisément les objets dont on veut capter la lumière - galaxies, quasars, étoiles - et les spectrographes alimentés par les fibres optiques qui analyseront la lumière recueillie en la décomposant en multiples longueurs d’ondes. 
          Looking Ahead        
Earlier this month the 2011B observing schedule for the 200-inch Hale Telescope was announced. The astronomers who applied for time in early April finally found out if and when they will be coming to Palomar from August through January.

I thought that the readers of Palomar Skies might like summary of the projects coming our way this fall, so here goes.


Photo by Iair Arcavi.

Transients are all the rage and 13 nights, spread out across the months, will be devoted to following up on objects discovered with the Palomar Transient Factory survey. An additional four nights will be devoted to doing similar work, but for transients discovered via the Catalina Real-Time Transient Survey. Both of these programs will primarily use our visible light spectrograph to identify the type of transients discovered. One other night will specifically devoted to a particular type of supernova known as a Type Ia.

The other big item on the agenda for 2011B is the study of exoplanets. Some of this is follow-up work from the Kepler mission. 14 nights are devoted to various studies on Kepler exoplanets or their host stars. Much of this is visible or near infrared spectroscopy, but some of it also makes use of our newly souped-up adaptive optics system known as PALM-3000. This high-resolution imaging system will be used 12 nights to study and hunt for exoplanets and planet-forming disks of debris located around young stars. Using instruments other than the AO system, two nights will be used to study some of these disks discovered by the WISE mission and another two to study some “hot Jupiters” as they are seen to transit their host stars. All together that comes to 30 nights of exoplanets in 2011B or 1/6th of the telescope time.

Speaking of planets and things that orbit a star, worlds of our own solar system are a subject of study too. This includes studies of asteroids (8 nights), the Galilean moons of Jupiter (1), the irregular satellites of the outer planets (2), the atmosphere of Uranus (1), and the frozen world located beyond Neptune in the Kuiper Belt (2).

Looking a little further out, 12 nights will be devoted to studying brown dwarfs, so called “failed stars” – objects that are more massive than a planet but not massive enough to sustain nuclear fusion the way that stars do. Many of the objects to be observed were first discovered by the WISE mission.

Lots of stellar astrophysics will be going on as our astronomers study star formation (3), young stars and protostars (4), young variable stars, novae (4), white dwarfs (2), x-ray binary systems (1). The presence of dark matter in our own galaxy will be mapped via studies of the motions of RR Lyrae type variable stars that are part of the Pisces tidal stream (3).


Photo by Iair Arcavi.

Looking beyond our galaxy is still a big part of science at Palomar. In fact, aside from engineering time, it comprises the rest of the time on the schedule. Massive stars and the chemistry of the stars in M31 (aka the Andromeda Galaxy), our nearest big galaxy, will be the subject of study for 8 nights. Included on the list are blue compact dwarf galaxies (2), massive elliptical galaxies (5), hyperluminous galaxies (1), low-luminosity star-forming galaxies (5), galaxies known as Lyman-alpha emitters (7), luminous infrared galaxies (7), and galaxy clusters (6). Five nights will be directed toward the evolution of galaxies and six nights will be devoted toward using the Cosmic Web Imager instrument to map out the presence of gas located between galaxies.

Supermassive black holes, which lie at the core of quasars and various galaxies with active galactic nuclei are to be studied for six nights, while quasars themselves are studied another seven nights. The environment in and around another type of active galaxy – radio galaxies— is to be studied for five nights.

It takes time to keep the telescope & its instrumentation in tip-top shape. Seven nights will be lost because we will be re-aluminizing the 200-inch mirror in October. An additional twelve nights will be spent on engineering various scientific cameras, mostly related to our new PALM-3000 adaptive optics system. Two of those nights will be a demonstration of a new instrument known as ARCONS – the ARray Camera for Optical to Near-IR Spectrophotometry. It is likely that there will be science observations on a good fraction of these “engineering” nights.

Finally, we will be closed to astronomy and engineering December 24 & 25 for our only two holidays of the year.

There is the summary of what we will be looking at from August through January. Hopefully I didn't miss anything.
          Beta Persei (Algol)        

"...the Gorgon's head, a ghastly sight, deformed and dreadful, and a sight of woe".
- Homer, writing of Algol in the Iliad.

algol!

This is a PSPC image of a portion of the Perseus region of the sky. The image was taken by the ROSAT spacecraft and is courtesy of the Max Planck Institute.

A Look at Algol

Algol is one of the most popular and well known variable stars in the sky. One of the reasons for this is that it is a star which can be observed with the unaided eye. Another reason is because it has a relatively short period of less than three days. This means a new observer can go outside everynight and see a complete cycle of Algol in their first week of observing if the star is visible at night in their location.

Algol is an eclipsing binary star system 93 light-years away as determined by the Hipparcos satellite. The main star is a B8 main-sequence star 3 times as large as our sun and the secondary star is a K2-type subgiant. Together they rotate around each other. As seen from Earth, when one star blocks our view of the other star its overall brightness changes. There is a very faint third star in the system. It is an F1 main-sequence star orbiting the inner pair every 1.86 years.

Algol's variability was discovered in 1667 by the Italian astronomer Geminiano Montanari making it one of the first ever non-nova variable stars discovered. John Goodricke of England is credited with the discovery of Algol's periodicity in 1782-83. It was apparently also independently discovered by a German farmer named Palitzch. At first it was believed that a planet was causing the eclipses. In 1881 astronomers theorized it was actually an eclipsing binary system based on evidence presented by Edward Pickering, the Director of the Harvard College Observatory (HCO). In 1889 this theory was proven through spectrographic analysis by H.C. Vogel at Potsdam.

"The Demon Star"

Human history has not been kind to this star. Homer wrote of Algol in the Iliad: "...the Gorgon's head, a ghastly sight, deformed and dreadful, and a sight of woe". Some common names for Algol are The Demon, the Demon Star, the Blinking Demon, the Ghoul, and the Spectre's Head. Sounds rather more like members of a hard rock goth band than a beautiful astronomical object. The earliest known maligning of this star is from the Arabian name Ri'B al Ohill, the Demon's Head. We also have Al Ghul meaning Mischief-maker. In Hebrew it is called Rosh ha Sitan, Satan's Head, and also Lilith, Adam's legendary demonic first wife (predecessor to Eve) according to Babylonian myth. 17th century maps referred to it as Caput Larvae, a translation of "The Spectre's Head". The Chinese referred to it as Tseih She, the Piled-up Corpses. Even astrologers refer to it as the worst star in the heavens to be involved with. More recently, the name Algol has been given to a violent video game. What does a star have to do to get respect?

"The Algol Paradox"

One way is to excite scientists. Despite its popularity and the attention focused on Algol, it still is not fully understood and has a few surprises for researchers. Recently, "The Algol Paradox" is a term that has been used to describe a discrepancy in our theories of stellar evolution. The primary star should expand first due to its greater mass, yet we find that the secondary is the older star in the Algol system. Many theories abound about how this can be. The most popular is that the secondary star is indeed older than the primary. It is only smaller because it dumped a lot of its mass onto the younger star, making it more massive and subsequently to look beyond it's years.


The above light curve is based upon observations of Algol made and submitted by John Isles. It is printed in Chapter 11 of the Hands-On Astrophysics manual.

More Info

The text below was written by Dr. John R. Percy, former AAVSO president, and Dr. Janet A. Mattei, AAVSO director. It was originally published in the Royal Astronomical Society of Canada Observer's Handbook in 1995.

Algol (ß Persei) is the brigh eclipsing binary with deep eclipses. It is also the brightest and closest semi-detached binary, a type of binary system in which one component has filled its Roche lobe (the volume within which gas is gravitationally bound to the star) and is now transferring material to its companion.

Algol varies in V magnitude from 2.1 at maximum to 3.4 at primary minimum, with a period of 2.867315 days; this period, however, is slowly lengthening. The primary eclipse occurs when the fainter K2IV star passes in front of the brighter B8V star, and lasts for some 10 hours in total. Because the eclipse is partial, the minimum is not flat, but rounded. There is also a shallow secondary eclipse when the B8V star passes in front of the K2IV star. It can only be detected photoelectrically. The primary eclipse, however, can easily be detected with the unaided eye, and the magnitude and the time of minimum can be measured.

These images reflect modelled theories of the circumstellar flow of Algol. Results were published in the The Astrophysical Journal, 1995, 445, 939-946. The authors are John M. Blondin, Mercedes T. Richards & Michael L. Malinowski.

For More Information

For more information on observing eclipsing binaries contact the AAVSO Eclipsing Binary Committee Chairperson Gerry Samolyk (gsamolyk@wi.rr.com).

This month's Variable Star of the Month was prepared by Aaron Price.


          Planetary System Gliese 581        
Planetary System Gliese 581

After more than four years of observations using the most successful low-mass exoplanet hunter in the world, the HARPS spectrograph attached to the 3.6-metre ESO telescope at La Silla, Chile, astronomers have discovered in this system the lightest exoplanet found so far: Gliese 581e (foreground) is only about twice the mass of our Earth. The Gliese 581 planetary system now has four known planets, with masses of about 1.9 (planet e, left in the foreground), 16 (planet b, nearest to the star), 5 (planet c, centre), and 7 Earth-masses (planet d, with the bluish colour). The planet furthest out, Gliese 581d, orbits its host star in 66.8 days, while Gliese 581 e completes its orbit in 3.15 days.

Image Credit: ESO/L. Calçada
Explanation from: https://exoplanets.nasa.gov/resources/174/
          Kate Bush: (Another) Whole Story        
This just in:



I have finally updated the Special Artists section of femalefront.com to add a tribute to a very special artist indeed: The amazingly gifted Kate Bush.

I had originally intended "Special Artists" to be the main section of the website, but it turned out to be the one that I updated the least. The music from these artists is so meaningful to me, that it's difficult to properly express in writing, and Kate has been the biggest challenge so far; but I gave it a shot, and I think that the resulting wall o' text is testimony to her influence on me.

This particular tribute was prompted by my finally purchasing her long-awaited album Aerial (pictured above). One thing I didn't point out in the review was the amazing album cover. To me, it initially looked like what it is: A series of jagged rock formations rising out of a still lake, with a sky of honey reflected in the water. But if you look carefully, you'll see that the image also resembles a spectrograph -- a picture of sound waveforms, similar to how a heart monitor graphs cardiac activity. How fucking cool is that? (Rhetorical.)

So, if you're brave enough and have lots of free time, click here to go directly to the article; or here for the "Special Artists" section's main page.
          What professional astronomers know about telescopes (often, not much!)        
Professor Astronomy and the Kitt Peak telescopes.
Yours truly at Kitt Peak in 2002 (I think).
Most people assume that we astronomers know everything there is to know about telescopes.  After all, we use giant ones for much of our work!  So it shouldn't be surprising that one of the most common questions we get asked (after the black holes and aliens have been addressed) is something like: "I've been thinking about getting a telescope.  What should I get?"

Many of these people are then quite disappointed to find out that I cannot help them much.  Sure, I give them the standard (and excellent, IMHO) advice that they should avoid $49 specials at Walmart, start with binoculars and then, if still interested, progress to something like an Astroscan. (Full disclosure - I own an Astroscan and love it, but I don't get any compensation whatsoever to talk them up).

But if you ask me which is better: a Celestron NexStar or an Orion StarMax, and I will give you a blank star.  I have no clue.  Or if you ask me why your iOptron SmartStar Maksutov has this weird coma when you put a certain filter in but not with a different filter by the same manufacturer, and I'll only be able to blurt out the obvious "maybe there is something wrong with the filter?"

Most professional astronomers probably know less about telescopes and the nitty-gritty details about how they work than many amateur and semi-pro astronomers.  Certainly I understand optics, and I know the basics of telescope design and operation.  When I am observing, I can tell if something is wrong and have helped diagnose the problem through testing.  But if I'm using the Keck Telescope and determine that a metal plate in the spectrograph is blocking most of our image, I don't go out into the dome and start banging on things with a wrench.  In fact, I wouldn't even know where the metal plates in the spectrograph are.  I call the engineers who come and fix everything.
A picture of the sky with a metal plate blocking three-quarters of the view.
It doesn't take a rocket scientist to see that something is blocking this picture of the sky.  Fixing it is altogether different.  (Keck I Telescope, August 2001)
 There are exceptions to this ignorance.  For example, our planetarium director, Dr. Kent Montgomery, was building his own telescopes as a teenager.  He directed the construction of our A&M - Commerce observatory, and has overseen its operation since.  I would have struggled mightily with these tasks, but Dr. Montgomery and his staff have developed a nice system.

This week, Dr. Montgomery started a two week vacation.  We have two undergraduate students here as part of our Research Experience for Undergraduates program, and they are using our observatory almost nightly to study asteroids and extrasolar planets.  And weird things have started happening in their images - instead of nice round dots for stars, sometimes they are little trails.  That's not supposed to happen.

So, Monday night I went with our assistant planetarium director, her staff, and the students to troubleshoot.  We checked wire connections, telescope balance, camera connections, and everything we could think of.  Yet at certain parts of the sky, the images were still wonky (a scientific term).  I ran some tests that convinced me the problem was mechanical - something in our telescope was moving when it shouldn't - and I was even able to narrow it down to a list of three most likely things: the mirror was moving (but it seemed tight), our guide telescope was moving (but it seemed tight, too), or our camera was bending slightly (it seemed tight, but this was my personal guess).  But at this point, I didn't know what to do.

Since our summer students are here only 10 weeks, I didn't want to wait for Dr. Montgomery to return to fix the telescope, but I don't trust myself to go mucking about in the telescope's guts.  A quick Google search did not help, and my schedule doesn't have a lot of time for deep searches on Internet forums.

So I put out a call for help.  Rather than contacting my colleagues at other PhD institutions (most of whom would not know any better than I, and those with the requisite knowledge are busy working on 2 to 30 meter telescopes and probably not likely to know much about modern 0.4-meter commercial telescopes), I emailed some contacts at the AAVSO and at the Central Texas Astronomical Society.  Within a couple of hours, I had a very detailed and extraordinarily diagnosis and likely resolution from an expert citizen scientist named Tom Krajci.  I still don't trust myself with the repairs, but at least we know what is going on and have some ideas how to minimize the problem until Dr. Montgomery returns.

I am very grateful to Tom and Mike Simonsen at the AAVSO as well as Brad, Willie, and Dean at the Central Texas Astronomical Society for their help, quick responses, and kindness not to roll their eyes when a bumbling novice like me comes along with a question.

Now, hopefully, you see why I can't give you detailed answers to your questions on commercial telescopes.  If you need help, your best bet is to find a nearby amateur astronomy club and ask - you'll get a better and more accurate answer than I would be able to help you with!  Now if you ever need help diagnosing problems with your 10 meter telescope, I may be able to help...
          RR Lyrae        


RR Lyrae, 1 degree field, DSS I survey plate
(copyright 1993-1995 CalTech/STScI)

Our Variable Star of the Season series returns from hiatus with a long-neglected astronomical gem: RR Lyrae, the prototype of one of the most important classes of variable star in astronomy. RR Lyrae and the class of pulsating variable stars that bears its name had a profound influence on astrophysics of the 20th Century, and it's likely that our understanding of both the size and nature of our Universe would be far more incomplete without these important stars.  RR Lyrae itself is a variable easily within view of most northern observers with modest telescopes or binoculars, and yet it remains a target for major observatories and research programs.  Both its visual prominence and its historical stature make it a fitting target for the September 2010 Variable Star of the Season.

RR Lyrae: the story begins

Harvard College was a hive of variable star activity in the late 19th century. The director, Edward Charles Pickering, and his extensive staff of "computers" -- women who carefully conducted many of the tedious calculations or searches of photographic plates at the observatory -- released dozens of papers and catalogues detailing their efforts in stellar cartography and photometry, asteroid searches and photometry, and variable stars.  One of these was a short paper in Harvard Circular Number 29 (1898) describing a simple technique for the study of short period variables.  In it, Pickering describes a technique for obtaining multiple photographic exposures of a star in a short amount of time -- a primitive but effective form of time-series photometry.  A photographic plate was alternately exposed and covered over preestablished intervals in a telescope whose alignment and tracking rate were not precisely aligned with the sky.  The result is that multiple exposures of a given star were obtained during an evening's observing, and that the periods for short stars might be more efficiently obtained.

A 1901 Astrophysical Journal paper by Pickering provides a list of sixty four new variables, one of which -- a star in the constellation Lyra -- was found using the method above on a plate from July 13, 1899. Examination of this plate by one of Pickering's staff, Wilhelmina Fleming, revealed a short-period, high amplitude star.  The star, with a range of more than 3/4 of a magnitude and period of just over half a day, clearly resembled those of the cluster variables (also discovered by Fleming in her analysis of plates from Solon Bailey's cluster survey in 1893).  Regular observations of this brightest "cluster variable" of the field commenced at Harvard as well as at other major observatories including Lick and Mt. Wilson.  RR Lyrae's brightness (between 7th and 8th magnitude) made it bright enough to observe spectroscopically in such a way that the changes in its spectrum could be traced throughout its cycle of variability.  This enabled astronomers to measure changes in spectral type, as well as to detect the presence of emission lines.

In his comprehensive 1916 review paper on RR Lyrae, Harlow Shapley made it clear that the binary hypothesis for variations in the "Cepheid variables" (with which he included the cluster variables) was inconsistent with both the spectroscopic and photometric variations; spectra suggested that the "orbits" of these binaries would have to be unphysically small, which photometry showing variations in the rise time to maximum required unphysical variations in the hypothetical orbital parameters.  Shapley also noted an important fact about RR Lyrae using the observations of Harvard's Oliver Wendell as well as his own: the times of maximum and the shape of RR Lyrae's light curve varies in a cyclical way with a period of around 40 days.  This effect, later known as the Blazhko Effect, has continued to provide a puzzle for astrophysicists to the present day.

Although RR Lyrae was not the first "RR Lyrae star" discovered -- both the cluster variables and the two field stars U Lep and S Ara came first -- RR Lyrae is by far the brightest, and its brightness made it an easy target for both photometrists and spectroscopists.  The name RR Lyrae variable subsequently became a fitting title for this important class of stars.

The Instability Strip

The RR Lyrae are members of an elite class of pulsating variables known as instability strip pulsators.  These stars, all confined to a narrow region of the Hertzsprung-Russell diagram, pulsate for the same reason: pulsations are driven by radiation being partially blocked from escaping the star, and the resulting increase in pressure and temperature makes them expand.  When gravity makes them contract again, the cycle repeats.  Due to the physical properties of stars and stellar interiors, only stars with very specific physical properties can do this, and those that can lie on a narrow diagonal strip of the H-R diagram running from hot, blue, and faint stars at lower left, to cooler, redder, and brighter stars at upper right.  Where this strip intersects a common population of stars within the H-R diagram is where you'll usually find pulsators.  Where it intersects the white dwarf sequence, you find the ZZ Ceti (DAV white dwarf) stars.  Where it intersects the main-sequence, you find the delta Scuti stars.  Where it intersects the post-main sequence, you find the Cepheid variables and W Virginis stars.  And in low-metallicity stellar populations, where it intersects the horizontal branch is where you find the RR Lyrae stars.  The RR Lyrae have intermediate luminosities between those of the (brighter) Cepheids and (fainter) delta Scuti stars.

The RR Lyrae stars are very evolved members of lower-metallicity stellar populations.  They have evolved through the main sequence, burned all of the hydrogen in their cores, and then made one quick run up the post-main sequence red giant branch and settled back onto the horizontal branch -- a short period of a low-metallicity star's life where it burns helium in its core and hydrogen in a shell around the core.  RR Lyrae stars are subgiants, more luminous than our Sun, but less luminous than the Cepheid variables.  Globular clusters with well-defined horizontal branches can sometimes have significant numbers of RR Lyrae stars in them, a fact that we can put to very good use here on Earth.

Cluster variables, the Universe, and Everything

RR Lyrae stars are astrophysically interesting in their own right, but what makes them most interesting is how they can be used. Another of the Harvard computers, Henrietta Swan Leavitt, was largely responsible for discovering another peculiarity of stars on the instability strip.  Leavitt studied the Cepheid variables in the Small Magellanic Cloud, measuring their apparent magnitudes and their pulsation periods.  The Small Magellanic Cloud was an important target because it was (correctly) assumed that all of the stars in the Cloud were physically associated, and were at approximately the same distance from the Earth.  By 1912 Leavitt established a clear relationship between the apparent brightness of these Cepheid variables in the SMC and their pulsation periods -- the brighter the star, the longer the period.  Further, it was a very tight and well defined relationship. You could estimate with very good accuracy how bright a Cepheid would be given its period and vice versa.


The PL relation for Cepheids in the SMC, showing magnitude on the y-axis versus log(Period, days) on the x-axis.  From Leavitt and Pickering 1912 (Harvard Circular 173).

This was an amazing discovery because of what it implies: (a) if the period-luminosity relation is universal for all stars, and (b) if you can find some way of calibrating the relation using Cepheids of known distance, then you can use Cepheids and other instability strip pulsators to measure distances.  Astronomers were soon able to calibrate this relationship using nearby stars with distances known by parallax, and they indeed confirmed that the relationship between period and luminosity was real and universal.  This relationship, known as the Period-Luminosity relation, was critically important to our eventual understanding of the nature and size of the Milky Way and of the size of the Universe. Harvard Astronomers Solon Bailey and Harlow Shapley were major players behind the adoption and use of the cluster variables as distance indicators.  Shapley was himself a participant in The Great Debate of 1920 between himself and Heber Curtis on the topic of the size of the Milky Way and the nature of "spiral nebulae" (now known to be other galaxies like our own).  Much of the argument centered on the globular clusters -- their distances and location within the Milky Way.  Parts of Shapley's arguments hinged both upon the distribution of globular clusters, and their distances from us.  The cluster variables -- mostly RR Lyrae stars -- were used as "standard candles" to measure the distances to the globular clusters, and so provided us with a first glimpse of the true size of the Milky Way.


RR Lyrae stars in Messier 3 (images and animation copyright J. Hartmann, Harvard U., and K. Stanek, Ohio State U.)

The relationship between a pulsator's period and its luminosity is know known as the Leavitt Law.  It has been used to measure everything from the distances to Cepheids, RR Lyrae, and delta Scuti within the Milky Way, to measuring the distances to galaxies nearly 100 million light years away.  It is still used today as a measuring tool in the cosmos, and there are constant efforts to better understand and refine this relation for all of the individual classes of stars on the instability strip.

A Century-old mystery: the Blazhko effect

In 1907 the Russian astronomer Sergei Blazhko first noticed the modulating amplitude of RW Draconis' pulsation light curve.  Unlike other similar pulsators, its light curve wasn't regular from cycle to cycle, but changed in both amplitude and shape in a regular and predictable way.  This effect came to be called the Blazhko effect, and was soon discovered in many other high-amplitude RR Lyrae stars (those of type RRab).  The class prototype RR Lyrae was itself found to be a Blazhko star by Harlow Shapley, with a Blazhko period (the time it takes to go through one Blazhko modulation cycle) of about 40 days.  Thus the brightest of the RR Lyrae stars also has this peculiarity in pulsation.  One might assume that since the Blazhko stars have been known for so long and include the brightest member of the class that the effect would be well understood by now, but this curious phenomenon has remained mysterious to the present day.  A number of explanations exist and great progress has been made very recently, but a definitive cause has yet to be proven.

What are some ideas?  One of the earliest hypotheses was that the Blazhko stars were multimode pulsators in which the main pulsation -- the radial fundamental mode -- was interacting with one or more weak non-radial modes to create the beating pattern of the amplitude modulations.  Some additional refinements to this included the addition of rotation, and a non-linear interaction between the pulsation modes.  Another possibility was that there are magnetic cycles within these stars similar in nature to the 11-year solar magnetic cycle but on a shorter timescale.  Further refinements to that theory include the idea that the rotation axis of the star is not aligned with the magnetic poles, that there's an interaction with magnetic fields and convection, or perhaps some combination of all of these.  Work by Chadid et al suggests that magnetic fields are probably not the cause of the Blazhko effect; she and her collaborators found that RR Lyrae itself has no strong magnetic field (at least above a limit of 80 Gauss), and so its Blazhko effect must be due to something else.  However, no one theory has been proven beyond a shadow of a doubt.

The Blazhko phenomenon remains a major topic of research for the stellar variability community, and there are several major facilities (including the CoRoT satellite shown here) spending time observing these stars.  Where is the field headed?  Right now, there are two things needed to make good progress: very high precision photometry, and high-resolution time-series spectroscopy.  The high-precision photometry will aid researchers in accurately measuring the shape of the light curve, and in Blazhko stars every small bump and wiggle can have significance.  Ground-based photometry at the level of a few millimagnitudes of accuracy is still being collected and used, but the micromagnitude precision and gapless coverage offered by satellites like CoRoT and Kepler may provide important new clues of their own.  Indeed, Szabó et al. (2010) may have found an important clue to the Blazhko effect using ultra-precise Kepler observations of half a dozen stars.  They suggest that "period doubling" caused by a resonance of two pulsation modes may be responsible.  Period doubling, where there is apparent variation at twice the actual period, is seen in RV Tauri and (sometimes) W Vir stars, although in those cases it produces much greater irregularity.

Likewise, large ground-based telescopes with high-resolution spectrographs are also being turned toward these stars, most notably RR Lyrae itself.  As Geza Kovács noted in his 2009 review, "...accurate time-series spectral line analysis [will] reveal any possible non-radial components and thereby let [us] include (or exclude) non-radial modes in explaining the Blazhko phenomenon."  Why is this?  A non-radial pulsation means that the star is not pulsating in spherical symmetry -- different parts of the star's surface are moving in and out at different times, and the shape of the surface depends upon the type of mode that's pulsating.  Since different parts of the star are moving in different directions at different speeds, and this may appear in a spectrum of the star as asymmetries in absorption line profiles.  An absorption line in a stationary gas will have a line profile that is similar to a Gaussian -- symmetric, with one central peak.  But if different parts of the star are moving at different speeds relative to our line of sight, then each parcel of gas will have its own red- or blue-shifted line profile resulting in a single line profile with waves and bumps.  These features may also shift around in wavelength if the star is rotating.  Careful analysis of the changes in line profile with time may reveal the presence of non-radial modes, or it may eliminate the possibility.

As those of you doing spectroscopy know, it's much easier to obtain a spectrum of a bright star, and the higher the resolution of the spectrum, the longer it takes to get good signal-to-noise.  That's as true for a spectrograph on a major ground-based telescope as it is for the one on the C11 in your backyard.  Since RR Lyrae is the brightest Blazhko star of the bunch, it remains an important target for both spectroscopic and photometric observations by the research community.  In particular, RR Lyrae was a primary target for the Blazhko Project of the University of Vienna, and the star has been a target for several collaborative observing programs by Horace Smith of Michigan, Katrien Kohlenberg of Vienna, and many other collaborators.

RR Lyrae and the AAVSO

Although it is not formally one of the target stars of the AAVSO's Short Period Pulsators Section (nor of its predecessor, the AAVSO RR Lyrae Committee), the AAVSO has over 8500 observations of RR Lyrae, about half of which are visual, and the other half are from intensive CCD time series by two observers.  The AAVSO has small stretches of visual observations, typically one season by one observer, between 1976 and 1995 from which visual times of maximum (TOMs) can be derived.  Starting in 1995, the AAVSO's visual community began observing this star in earnest, and there are a number of cycles from which TOMs can be derived up to and including the present day.  Data for RR Lyrae dates back well before the AAVSO archive however; you can find some of these data archived at the GEOS RR Lyrae database.

     

Phase diagrams of RR Lyrae using AAVSO data: (left) Visual data, JD 2450200-2450400; (right) V-band data, JD 2453941-2453992, where different colors are different cycles.

The RR Lyrae research community has shifted away from visual observations to the use of CCD timings, since they allow higher time and magnitude precision and can reveal finer details in the behavior of RR Lyrae star timings than can visual data.  While the complex problems of RR Lyrae astrophysics require instrumental observations for TOMs and for light curve analysis, RR Lyrae remains an enjoyable visual target with minute-to-minute changes sometimes visible during the rising branch of the pulsation. 

The AAVSO Sequence team has recently updated and expanded the sequence; visual observers should use B-scale charts and observe with a wide-field instrument like binoculars or a low-power telescope.  Instrumental observers should have a number of comparison stars to choose from within the field, but comparisons comparable in brightness to RR Lyrae itself (between V=7.2 and 8.2) will produce optimal signal-to-noise.  As with visual observing, a wide-field camera will provide the greatest range of comparison stars.  As always, we encourage instrumental observers to fully reduce, calibrate, and transform their observations, including airmass corrections and transformation to a standard system.  This will make it much easier to combine your observations with those of other observers.

RR Lyrae is an understated gem among the variable stars in the AAVSO archives.  While there are many RR Lyrae stars actively pursued by AAVSO observers and the research community, RR Lyrae itself remains an important target for modern astrophysicists.  More than a century after its discovery, the secrets of this bright northern variable have yet to be fully uncovered.  However, there is real hope and excitement within the astrophysics community that the complex problems of the variability of RR Lyrae and other stars like it may finally be yielding to more and better observational data more than a century after its discovery.  Our Variable Star of the Season, RR Lyrae, shows the unbroken chain of discovery and understanding beginning more than 100 years ago and stretching to the present day.

For more information:

 

This Variable Star of the Season article was written by Dr. Matthew Templeton, AAVSO.


          Case Of The Spectrograph by Counterspy        
This week on Relic Radio Thrillers, Counterspy brings us their story from December 3, 1950.  Here is, The Case Of The Spectrograph. Download Thriller344
          RR170: Cabin B-13 and Counterspy        
Cabin B-13 starts things off this week with an episode from December 12, 1962 titled The Bride Vanishes.  Then it’s Incredible But True and Two Heads Are Better.  We finish off with David Harding, Counterspy and The Case Of The Spectrograph from December 3, 1950. [audio:http://www.archive.org/download/RelicRadioShow/RelicRadio170.mp3] Download
          Kiddie Lit‑ter - February 2016        
February 2016 | Kiddie Lit‑ter | Harper's puzzle solution

Hello, Dear Readers! Are you ready for puns obscene and filfy in their puntacularity? Are you ready for some audacious head canon from Richard E Maltby Jr? Then you are ready for February 2016.


The Theme!

Four clues given without number of letters, and four possible locations in the fill. A resultant theme‑relevant sentence running around the perimeter. The theme clues turned out to be: not classic cryptic clues per se but rather set‑ups for some outrageous punnery themed around children's books. At first glance of the puzzle title we thought, sortof as a joke, that the theme would point to Harry Potter. Then we saw clue c) which references Severus Snape, and o shit! For real there's some Harry Potter up in here!
  • a) Bear stage = POOHBERTY
  • b) Like a deer that goes either way? = BAMBIDEXTROUS
  • c) Severus Snape, speculatively? = POTTER FAMILIAS*
    * more on thissun inna sec
  • d) Wild elephant acts? = BABARISM
And the meaningful perimeter sentence:
  • Stastically speaking, six out of seven dwarves are not happy.
Except we had it wrong, Dear Readers, and entered “six of the seven”:
SIX OF THE SEVEN | Tacky Harper's Cryptic Clues
All the crosses work, except 41A starting with EIACR_ which is just piffle. Twas there an error? Twould there be yet another apology in the upcoming answer key? Twould not. Twerror was twours this twime.
SIX OUT OF SEVEN | Tacky Harper's Cryptic Clues
Obv we didn't check against the dum anagram. Didn't even consider “out of” but it definitely reads more natural. “Nine out of ten doctors agree” blah blah. Definitely. Thus 41A becomes sensible and solveable, yea tho it be anachronism:
  • 41A) Old‑time hack providing back lot, perhaps (6)
    ((providing = IF) back = FI) (lot = ACRE) = FIACRE
Never hearda fiacre before, but it's this:
fiacre | Tacky Harper's Cryptic Clues
Image courtesy Brittannica


But so ok that's settled, so now going back to c) and ok so whoa, just, whoa. Whoa. Slow your roll, slow your heart rate. Whoa. Ok. So in order to solve this puzzle one must entertain Maltby's wild speculation that Severus Snape is Harry Potter's dad???

This claim is so far out there, we wouldn't even tag it a SPOILER. Maltby is a Snape Daddy Truther. Interestingly, in poking around Quora and Yahoo! Answers posts for more information (“information”) we came across this passage lifted from Harry Potter and the Half‑Blood Prince:
[Harry Potter,] you look very like your father.
Ok but then so next question, Prof Slughorn: when you say “father,” to whom exactly do you refer and WHAT DO YOU REALLY KNOW?????
Harry Potter and Snape hug | Tacky Harper's Cryptic Clues
Image courtesy Deviant Art user mathiaarkoniel

Do you feel that, Dear Readers? That was a shift in the Force as we, too, became a Snape Daddy Truther. Potter Familias. It makes so much sense! Not vis á vis the million jillion times when one of James's contemporaries tells Harry, “zomg you look exactly like him so cray.” But narratively. Like in a Campbell Masks of G0d archetypal human stories sense. Like if we were writing Harry Potter as a TV show, this would totally be our second season reveal, not long after a mid‑season reveal that James was a shitty bully in high school**.
** which is, of course, actual canon

We floated clue c) to our friends Clara, Dr Jesse, and Auntie Maim. All declared it “tacky.” Auntie also called it “wildly inappropriate.”

Puzzle‑wise, or unwise, we much dislike balancing a heavy load of uncrossed theme letters with “well but they form this anagram so that's how you can check.” Meh.


Highlights!

  • 12A) Bird track (4)
    Bird = track = RAIL
Hadna hearda this birda before, but forgiven for the neatness of a two‑word cryptic clue! Double syns of this nature are our new second favorite, directly after anagrams of course :)
rail (bird) | Tacky Harper's Cryptic Clues
  • 13A) Arthur, for one; Teddy, not quite (3)
    (Teddy = BEAR) not quite = BEA
Automatic true love for reference to Grandpa Bea Arthur, rest in peace.
Grandpa Bea Arthur | Tacky Harper's Cryptic Clues
Did you know she was in the Star Wars Holiday Special?? Bea Arthur | Tacky Harper's Cryptic Clues
  • 16A) With a zeal, I cut ingredients to make concrete (9)
    ZEAL I CUT * anagram = ACTUALIZE
So strong. Of course especially love potential anagrinds like CUT used instead to form the anagram. Mwa!
  • 18A) She left a chair for meatier diversion (7)
    MEATIER * anagram = EMERITA
Yas! Positive female presence in the puzzle! Twas a lotta that in this puzzle, actually. Perhaps the feminist yawp of Tacky Harper's Cryptic Clues has been heard??
  • 27A) Clothing that has an adversarial position (4)
    adverSARIal = SARI
Seeni sari often in the puzzle, but thumbs up for inclusive “clothing” rather than ethnically coded “Indian clothing” or “Eastern clothing” &c. Clothing of the people. Human normative. We had the first S in the fill and wanted this to be SCON, somehow. Like “adversarial position” = CON.
  • 32A) Director who made Isadora right size in a new format (5)
    (right = R) SIZE in a new format = REISZ
Fun! Some Dear Readers may recall that we're in the pool of potential Jeopardy! contestants until April 2017. We study every day. Some names and topics seem to come up disproportionately frequently in American trivia. That means, “we've seen them more than twice in the last six months.” Offa top those topics include:
  • the author Sinclair Lewis
  • Don Quixote
  • Isadora Duncan
  • &c.
We try to maintain at least “first paragraph of Wikipedia” knowledge about each of these. Isadora was an early 20th century French dancer. She was a fashionable Communist and she wore big red scarves, but the scarves were what killed her when one wrapped around the axle of her car. And then Grandpa Gertrude Stein said, “affectations can be dangerous.” Fuck yes, Gertrude Stein :)  We love that bitch.

Had never heard of Reisz but it's always good to collect more intel on Isadora D.
Isadora Duncan | Tacky Harper's Cryptic Clues
  • 36A) Head of trainees gets A‑minus for “Oscillating Wave” (7)
    (Head of trainees = T) gets A MINUS for oscillating = TSUNAMI
Nice. Thought for a long time this would be term from high school physics, ending in, like, ‑IUS or ‑NUS. Like HERTZ or something. This paragraph is where we reveal how little we remember of high school physics.
  • 38A) Rework G.O.P. script—reach for representing all colors (14)
    Rework GOP SCRIPT REACH = SPECTROGRAPHIC
O FOCK YES!! O GLORY YES!! This was a sweet anagrama. The only longy of its kind this puzzle, but so sweet and worthy. This was also the big solve this month courtesy husband Sweet V. Also a fun narrative. Reach for it, Republican buddies! Big tent, buddies! All the colors. Flip the script. Try.
Donald Trump w/ black pastors | Tacky Harper's Cryptic Clues
  • 50A) Group of rocket scientists, left of a wind tunnel (5)
    (Group of rocket scientists = NASA) (left = L) = NASAL
HAHAHA this is a fun way to get “nose.” Incongruency of “wind tunnel” (noun) and “nasal” (adj) is forgiven! Dear Readers are invited to quibble with us on this point in the Comments. Per Wise Tyler below, the “of” makes the definition side adjectival. Wise Tyler knows nose!
  • 1D) A pop group, Ache (4)
    ACHE * anagram = EACH
Was hung up for a long time that this was “pop” as in “soda” (what's up to my brothers and sisters in the Middle West!!) and that there might exist something like HECA, sortof a sister soda to NEHI. Woops. Also, Ache is a great name for a pop group! Gratuitous pic of mother Poly Styrene:
Poly Styrne | Tacky Harper's Cryptic Clues
  • 5D) Leak produces audible gasps (4)
    audible (gasps = OOHS) = OOZE
This was just so nice. And gross. Our dark secret is sometimes we like things that are gross.
  • 6D) The enemy, song without end (4)
    (song = THEME) without end = THEM
Fresh reference to the notion of Other! Separation is inherently antagonistic. Yas.
  • 7D) Power found in the gem onyx (8)
    tHE GEM ONYx = HEGEMONY
A daring word‑spanner! Hiding in plain slight! And a reference to stones of power, cf every anime ever, most excellent :)
  • 8D) Rattles used in the style of royal address for women (6)
    (in the style = A LA) (royal = R) (address for women = MS) = ALARMS
Ahhhh!!!!! YES! Unqualified apolitical “women” qua “Ms” which is wonderful to see! Could this be the most feminist Harper's cryptic crossword puzzle yet?
Miss Giddy from Mad Max: Fury Road | Tacky Harper's Crypic Clues
  • 9D) Brownie mix, mostly—an ingredient in tart (5)
    (MIX mostly = IX) an ingredient in (tart = PIE) = PIXIE
Yass!! Shout out to Brother Kevin Pollak and Brother Rick Overton, brownies from Willow.
Kevin Pollak and Rick Overton | brownies from Willow | Tacky Harper's Cryptic Clues
  • 19D) Leave time for Christmas morning—pressure comes later (6)
    (time for Christmas = December = DEC) (morning = AM) (pressure = P) = DECAMPS
Raise yer hand if you were expecting NOEL to rear her head [raises hand]. V nice surprise instead.

Our parents' dog Hank is a chewer and destroyer of toys. For Christmas this year we bought Hank a plushy shark toy made from special multi‑ply fibers. The lady at the pet store swore that no dog could chew through it. Hank loved his shark and ripped it apart within ten minutes. We showed video footage of the carnage to the lady at the pet store. She was not satisfactorily bashful. She offered to give us a fresh replacement shark. “You don't get it. Nothing in this store is strong enough,” we thought and did not say.
Hank and shark | Tacky Harper's Cryptic Clues
the shark lost | Tacky Harper's Cryptic Clues
  • 20A) Endorsement (obscure) seen at the front of book? (5)
    (obscure = BLUR) seen at the (front of book = B) = BLURB
So nice! So excellent for so many reasons! Ah just the tightness of book blurbs and book‑as‑in‑letter‑B. So good.
  • 22A) Works in tips from regulars under buddy system (4)
    tips from Regulars Under Buddy Sstem = RUBS
Wonderful! Thought it was DUOS for a while (buddies). Couldn't shake the image of Hall & Oates. You ever get that? The clue evokes an image that sticks?

personal story about working things in, rubbing
Our husband Vlad, aka Sweet V, aka The Sweet One, has many beautiful features (physical, spiritual, intellectual) and is super chill about them all (such chillness only compounding his beauty) … except for the softness of his feet. He is totally vain about how soft his feet are. Only good socks and the comfiest of shoes for the Sweet Feet! In contrast, our feet are quite dry and rough. The other night while sitting barefoot in the easy chair, we heard our heel FRIPPPP against the fabric. Yes, as if our feet were covered in rough Velcro. “That's it!” we said, and went in Internet search of a solution. This Marine's review of Dr Scholl's was charming, promising:
5.0 out of 5 stars • Afghanistan Tested, Me Approved, July 12, 2011

I have recommended this product to MANY Marines (males as well) and every single one of them felt the difference.

Source: Glamazon

  • 23D) Hunks involved in holdups? (5)
    STUDS (double syn.)
WOOT! Wut's up, sexualized male body? What, is up.

Dear Readers who follow us in real life may already be familiar with our blow‑by‑blow of Magic Mike 2 as understood from watching on a plane without headphones or subtitles. For those that read this blog for our writing style and sense of humor, rather than strictly for a post mortem of the Harper's puzzle, here is a clicky linky to said post:
http://ericaricardo.com/blog-151230.php
the Mikes from Magic Mike XXL | Tacky Harper's Cryptic Clues
  • 35D) Abbreviated birthday basket for farm horse (6)
    (abbreviated (birthday = date of birth) = DOB) (basket = BIN) = DOBBIN
What's up to the fam, what's up to the farm. Hadn't heard of “dobbin” before, but we like!
My Dobbin | Tacky Harper's Cryptic Clues
  • 37D) Hello! I'm going after a fish! (3)
    (Hello! = HI) going after A = AHI
Oh this was nice! So sweet and silly! Use of over‑frequent puzzle fish AHI forgiven!
  • 40D) A neat organization is a healthy company! (5)
    A NEAT organization = AETNA
We interpret this as a dark joke about health insurance corporate giants as “healthy companies” … haha NOT!
  • 44D) Intuit conclusions drawn from Jung or Otto Frank (4)
    conclusions drawn from JunG oR OttO FranK = GROK
Love grok. Every puzzle should have grok. Even if Stranger in a Strange Land has what we interpret as generally oppressive gender and sexuality orthodoxy. There's of course this ultra‑discouraging line said by Jill:
“Nine times out of ten, if a girl gets raped, it's at least partly her own fault.”
Another good example, again pinned on Jilly‑Jill:
Jill... had explained homosexuality, after Mike had read about it and failed to grok—and had given him rules for avoiding passes; she knew that Mike, pretty as he was, would attract such. He had followed her advice and had made his face more masculine, instead of the androgynous beauty he had had. But Jill was not sure that Mike would refuse a pass, say, from Duke—fortunately Mike's male water brothers were decidedly masculine, just as his others were very female women. Jill suspected that Mike would grok a 'wrongness' in the poor in-betweeners anyhow—they would never be offered water.

Source: Goodreads

Maybe these views were meant to be only those of ol' backwards silly Jilly? But so the other characters don't get on her case about it when she says that shit. In our Stranger in a Strange Land fan fiction of course such shit does not fly.
Stranger in a Strange Land book cover | Tacky Harper's Cryptic Clues
  • 47D) A special killer (3)
    A (special = SP) = ASP
Nice and neat! Tight tight tight! And many thanks for the reference to ASP without mention of Yas Queen Cleo.
black Cleopatra | Tacky Harper's Cryptic Clues

Lowlights!

  • 17A) Spell “a millimeter” upon entering? What for? (6)
    A (millimeter = MM) entering (What for = WHY) = WHAMMY
A “whammy” is a spell? Like a witch's spell? Like as in a span of time, like, “I need to sit for a spell”? [looks it up] Ok so like a witch's spell, interesting:
whammy
noun wham•my
: something (such as a magical spell) that causes someone to have bad luck

Source: Merriam Webs

  • 24A) A lot of athletes swarm to the left (4)
    (swarm = TEEM) to the left = MEET
Like a swim meet? [harsh Cockney accent] “Staht swimmin, then! The lot o' you!!”
  • 25A) In broken line, train little Helen (6)
    broken LINE (train = EL) = NELLIE
Whoa, Nellie. Never heard of this diminutive for Helen but that's fine. Our beef is with “train” = “el” for the millionth. Even if it gives us cause to reference our all‑time ever forever favorite scene from The Fugitive
aka Play That Back I Wanna Hear the Sounds of an Elevated Train
aka Don't Ever Argue with the Big Dog; Big Dog's Always Right:

  • 26A) Ward off untoward word in the Bible (4)
    WARD off untoWARD = UNTO
Barf. Couching this in the feeblest of idiom doesn't disguise the overly simple charade. Ai yi yi [for an eye].
  • 30A) County leader replaced by second‑level liberality (6)
    COUNTY leader replaced by (second‑level = B) = BOUNTY
Bro, so like, COUNTY and BOUNTY even rhyme, bro. Bro. It's not even like BROTHER to FROTHER. How about COUNTY to MOUNTS, and make that crossing 22D RUBS instead change to RUMS. And then how about this clue:
  • County center in a lady's magazine about horses (6)
Just a reminder and FYI, literally any time Harper's is in need of help with clues, just send us an email attached to a PayPal donation :)
  • 34A) Bull breaks into lodge that's packed (7)
    (Bull = OX) breaks into (lodge = EMBED) = EMBOXED
Um, so “bull” ≠ “ox” starting with: “ox” can be male or female; “bull” is necessarily male.
bull vs ox | Tacky Harper's Cryptic Clues
The differences continue:
1. The oxen are draft or pulling animals, usually used for cart transportation, or to pull plows.

2. While both are part of the bovine family, the oxen are a sub-genus of the male cattle, or bull.

3. Oxen are castrated, and breeding is more controlled and selective.

4. The typical ox is larger than the typical bull.

5. The ox and the bull have similar, yet unique, genetic DNA codes.

6. While they maintain religious and ethnic symbolism, they are often heralded separately.

Source

More importantly, EMBOXED is justa dum word. Save it for the Scrabbo board, where bulls*it ‑ED words with a medial X belong.
  • 48A) Old Chinese bread—there's a story to be told here (4)
    (story = TALE) to be told here = TAEL
Chinese tael | Tacky Harper's Cryptic Clues
We remember TAEL from an earlier puzzle (Honorable Mention - November 2014) which, ok, after a year that's fine to pull a refry. But TALE => TAEL is just very butt. At least give us a TAIL at least a homophone that, like, uses different letters. And if you weren't bored and dead by 48A, here's 49A for more of similar:
  • 49A) Where to put elements taken from soil? (4)
    SILO (pun)
“elements”? That's what the corn and the wheat and … ok. Unless we're mistaken, and we often are, this is one of the hermaphroditic ourobouri clues that consumes itself, both parts in one. Which is fine, but SOIL => SILO? These single letter translations make us SO IL(L).
silo | soil | Tacky Harper's Cryptic Clues
  • 2D) Astringent person who went to college (4)
    Astringent = person who went to college = ALUM
Simple double syn. Enjoy the phrase “astringent person” but otherwise this was meh. Not as meh as the next clue, tho! Beholt:
  • 3D) It's necessary to feel yet hard to grasp (4)
    fEEL Yet = EELY
Much as a chef might re‑use old fish as part of a stew, this read as an attempt to make the over‑frequent entry EEL seem new and fresh. With the right chef such attempt might be successful, but often it just stinks.
eel | Tacky Harper's Cryptic Clues
  • 31D) A number of layers—that could be plenty (3‑3)
    could be PLENTY = TEN‑PLY
What number? Oh, just “a” number. Buh! We're curious about what ten‑ply creation is imagined here? Cardboard? Toilet paper? A shark toy that even Hank could not take apart?
  • 39D) Two thirds of league breaks up—someone in Britain appears (4)
    (Two thirds of LEAGUE = LEAG) breaks up = GAEL
Uh. The sun set on the British Empire, thanks. Here's our favorite Gael, tho [this month's Nerd Hot Guy]:
Gael Garcia Bernal | Tacky Harper's Cryptic Clues
Gael Garcia Bernal with glasses | Tacky Harper's Cryptic Clues
  • 42D) Golfer Aoki is a nothing (4)
    IS A (nothing = O) = ISAO
Uh, whut? Isao Aoki, World Golf Hall of Famer with a generous name fulla vowels, is a “nothing”? Gross!
Isao Aoki | Tacky Harper's Cryptic Clues


The Tacky

  • 29D) My friend in the hood gets colic, turning green (8)
    (My friend in the hood = BRO) gets COLIC turning = BROCCOLI
Um. How about “my urban friend” how about “my black friend” how about just say what you mean. Buh. “the hood.” Gross.

Altho of course enjoy BROCCOLI in the puzzle.
Samuel L Jackson | broccoli | Tacky Harper's Cryptic Clues


Comments are fuel for more blogging.


          WOW this community is quiet        
Can´t believe no one posted THIS yet!

Also, I´m particulary interested in this part of the article, but I´m not following what it´s saying about how the method of detecting planets works:

Confirmation of a planet, however, requires additional observations, usually of its star’s wobbles as it gets tugged by the planet going around. The gravitational pull of planets as small as the Earth on their parent star is too small to measure with the current spectrographs. And so the astronomers resorted to a statistical method called Blender, developed by Dr. Fressin and Guillermo Torres of the Harvard-Smithsonian Center, in which millions of computer simulations of background stars try to mimic the Kepler signal. They concluded that Kepler 20e was 3,400 times more likely to be a planet than background noise, while the odds in favor Kepler 20f being real were 1,370 to 1.

Someone can clarify this for me? Please and thank you!
          Alert Notice 487: Supernova 2013dy in NGC 7250 = PSN J22181760+4034096        

July 19, 2013

Event: Supernova 2013dy in NGC 7250 (Lacerta) = PSN J22181760+4034096

Independent discovery by:
 - Lick Observatory Supernova Search (LOSS), reported by C. Casper, W. Zheng, W. Li, and A. V. Filippenko (University of California at Berkeley) and S. B. Cenko (Goddard Space Flight Center)
 - Kuniaki Goto (Miyoshi-shi, Hiroshima Prefecture, Japan), communicated by Shoichi Itoh (National Astronomical Observatory of Japan)

Discovery magnitude:
 - LOSS: CCD magnitude 17.0, on unfiltered Katzman Automated Imaging Telescope (KAIT) images
 - Goto: about 16, using 35-cm Schmidt-Cassegrain telescope

Discovery date:
 - LOSS: 2013 July 10.45 UT
 - Goto: 2013 July 11.735 UT

Coordinates: R.A. = 22 18 17.60, Decl.= +40 34 09.6 (2000.0)
SN 2013dy is offset 2.1" west, 24.9" north from the nucleus of NGC 7250 (coordinates and offset from LOSS).

Spectra: SN 2013dy is a Type-Ia supernova discovered one to two weeks before maximum, according to spectra by:
 - D. D. Balam (Dominion Astrophysical Observatory, National Research Council of Canada (NRCC)), M. L. Graham (Las Cumbres Observatory Global Telescope, University of California at San Diego), and E. Y. Hsiao (Las Campanas Observatory) obtained on Jul 13.31 UT with the NRCC 1.82-m Plaskett Telescope;
 - J.-J. Zhang (Yunnan Astronomical Observatory (YNAO)) and X.-F. Wang (Tsinghua University) obtained on Jul 14.75 UT with the 2.4-m telescope (+YFOSC) at YNAO LiJiang Gaomeigu Station;
 - W. Zheng (University of California, Berkeley), S. B. Cenko (Goddard Space Flight Center, NASA), K. I. Clubb, O. D. Fox, P. L. Kelley, and A. V. Filippenko (University of California, Berkeley), and J. M. Silverman (University of Texas) obtained on Jul 11.7 with the 10-m Keck II telescope (+ DEIMOS spectrograph) at Keck Observatory.

Observations reported to the AAVSO:
2013 Jul 8.45 UT, <18.5 U (unfiltered KAIT CCD photometry, via CBET 3588);
10.086, 19.1 (F. Ciabattari, Borgo a Mozzano, Italy, 0.5-m Newtonian telescope + FLI Proline 4710 camera, via CBET 3588);
10.7, 16.6 (A. Mantero, Bernezzo, Italy; 0.25-m f/4 reflector, via CBET 3588);
11.909, 16.0 (G. Masi and F. Nocentini, remotely using 43-cm robotic telescope, Virtual Telescope Project facility in Ceccano, Italy, via CBET 3588);
11.994, 16.3 V (M. Martignoni, Magnago, Italy;0.25-m f/10 Schmidt-Cassegrain reflector, via CBET 3588);
12.423, 15.7 (L. Elenin, Lyubertsy, Russia, and I. Molotov, Moscow, Russia; remotely using 0.45-m f/2.8 telescope at ISON-NM Observatory near Mayhill, NM, via CBET 3588);
14.37, 14.5 U (KAIT, via CBET 3588);
15.96528, 14.5 (K. Wenzel, Grossostheim, Germany, visual);
16.19444, 14.4 (T. C. Hoffelder, Norway, ME, visual);
16.93750, 13.9 (Wenzel, visual);
18.91319, 13.5 (Wenzel, visual);

Charts: Charts for SN 2013dy may be created using the AAVSO Variable Star Plotter (VSP) at http://www.aavso.org/vsp.

Submit observations: Please submit observations to the AAVSO International Database using the name SN 2013dy.

Notes:
a. Announced on IAU CBAT Central Bureau Electronic Telegram 3588 (Daniel W. E. Green, ed.). Except for observations reported to the AAVSO and Note e, all information in this Alert Notice comes from CBET 3588.

b. SN 2013dy was designated PSN J22181760+4034096 when it was posted on the CBAT TOCP webpage (http://www.cbat.eps.harvard.edu/unconf/tocp.html). Note that the offset was incorrectly posted on the TOCP page as 24.9" south.
 
c. Position end figures and additional observation details for all observations reported here via CBET 3588 are available in CBET 3588.

d. SN 2013dy images:
 - F. Ciabattari (Jul 10.086, 19.1), at http://www.flickr.com/photos/snimages/9277396759/
 - Andrea Mantero (Jul 10.7, 16.6), at http://www.flickr.com/photos/andreagalaxy/9261869119/
 - L. Elenin and I. Molotov (Jul 12.423, 15.7), at http://spaceobs.org/images/TOCP/PSNJ22181760+4034096-20130712.png).

e. J. Ryan (Harvard-Smithsonian Center for Astrophysics) reports in ATel #5216 (http://www.astronomerstelegram.org/?read=5216) that he and colleagues will be taking HST UV spectra of SN 2103dy 10 times over the next month, beginning 2013 July 21 ~11:00 UT. He requests observations at all wavelengths.

Congratulations to the LOSS team and to Kuniaki Goto on their independent discoveries!

This AAVSO Alert Notice was prepared by Elizabeth O. Waagen.
---------------------------------------------------‬

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Information on submitting observations to the AAVSO may be found at‭:‬
http‭://‬www.aavso.org/webobs

ALERT NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION

An Alert Notice archive is available at the following URL‭:‬
http‭://‬www.aavso.org/alert-notice-archive

Subscribing and Unsubscribing may be done at the following URL‭:‬
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          Sarah (Jack's secretary)        
RED DRAGON
Sarah is Jack Crawford's secretary. She orders a helicopter to transport Jack to collect the "Tooth Fairy" killer's note from Hannibal Lecter's cell at the Chesapeake State Hospital. She also transcribes dictation of an advertisement to be placed in The National Tattler which turns out to be from Lecter, and telexes it to CIA cryptography section.

She took a call from someone claiming to be "The Pilgrim" (which is Lecter's nickname for the "Tooth Fairy" killer) who was looking for Will Graham. The caller said he'd call again the next afternoon, by which time Sarah's desk had been fitted with a voiceprint spectrograph, tape recorders, and a stress evaluator. Sarah's role was to listen in on the calls and identify the voice of the person who called himself "The Pilgrim" and to signal to Beverly Katz to answer the call.

"HANNIBAL" (Four years before)
It is unknown if Sarah will appear before Season 4.
           The CASSINI ultraviolet imaging spectrograph investigation         
Esposito, L.W. und Barth, C.A. und Colwell, J.E. und Lawrence, G.M. und McClintock, W.E. und Stewart, I.F. und Keller, H.U. und Korth, A. und Lauche, H, und Festou, M.C. und Lane, A.L. und Hansen, C.J. und Maki, J.N. und West, R.A. und Jahn, H. und Reulke, R. und Warlch, K. und Shemansky, D.E. und Yung, Y.L. und George M. L, (2004) The CASSINI ultraviolet imaging spectrograph investigation. In: Space Science Review Kluwer Academic Publishers, Netherland. Seiten 299-361. ISBN ISSN 0038-6308.
          Alert Notice 173: Request to monitor cataclysmic variables during ORFEUS mission AND 1908+01 Nova Aquilae 1993 [V1419 Aql] AND Fading of 1910-33 RY Sagittarii AND Request to monitor 1834-23 V348 Sagittarii        

THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
BITNET: aavso@cfa8 SPAN: nssdca::cfa8::aavso
INTERNET: aavso@cfa0.harvard.edu
Tel. 617-354-0484    FAX 617-354-0665

AAVSO ALERT NOTICE 173 (July 7,1993)

REQUEST TO MONITOR CATACLYSMIC VARIABLES DURING ORFEUS MISSION

ORFEUS Mission: On July 17, 1993, the NASA's Space Shuttle Discovery is scheduled to launch a German-built, free-flying space platform equipped with an international cargo of science instruments. This first mission m the ASTRO-SPAS series of NASA and the German Space Agency (DARA) is called ORFEUS (Orbiting and Retrievable Far and Extreme Ultraviolet Spectrograph). The mission's primary goal during the planned 5-day science mission is to observe stars that emit most of their light in the ultraviolet band of the electromagnetic spectrum to help understand the evolution of these stars and their interaction with the interstellar medium. Once the instruments have completed their observations, the platform and the instruments will be retrieved and returned to Earth, where they will refurbished for later shuttle flights, at least three more over the next four years. NASA-Astrophysics Division is supplying us with a very informative pamphlet on ORFEUS mission which will be sent to you separately.

OBSERVATIONS OF CATACLYSMIC VARIABLES with the ORFEUS Mission: Astronomers at the Harvard-Smithsonian Center for Astrophysics and Lawrence Livermore National Laboratories at Livermore, California, will be observing some cataclysmic variables - dwarf novae (DN) and magnetic novalike (NL) variables - during the ORFEUS Mission and have requested our assistance. Below is a list of their primary observing targets during this mission.

Designation    Star       Type   Magnitude Range
0058+40        RX And    DN    10.3-14.5
0409-71        VW Hyi     DN      8.4-14.4
0814+73        Z Cam     DN    10.2-13.8
1813+49        AM Her    NL    12.4-15.3
2138+43        SS Cyg    DN     8.1-12.4
2209+12        RU Peg    DN     9.4-13.1

The astronomers are particularly interested in monitoring outbursts of the dwarf novae and the different states ("down" or "up") of the novalike stars.

Please monitor these stars between now and the end of the mission or the end July (which ever is later - in case of change in the launch date), and call in your observations of the outbursts of the dwarf novae, and the brightness state of AM Her, to AAVSO Headquarters, using the charge free 800 number  (800-642-3883) that was established for the monitoring of cataclysmic variables for NASA's EUVE mission.

In addition to the stars above, if any of the brighter dwarf novae go into outburst (i.e, with outbursts  brighter than 12.0 magnitude), please inform us at Headquarters, as these stars may also be observed  during the ORFEUS Mission.

SPECIAL NOTES ON 2138+43 SS CYGNI and 0409-71 VW HYDRI

SS Cygni: This dwarf nova went into outburst on May 22, right before the ASCA mission (see AAVSO Alert Notice 171). This outburst was an anomalous one, in which the rise to maximum was slow, and the outburst was faint and short. Since then, SS Cyg has been particularly active during quiescence, with our observers reporting it brightening to 10.6 and oscillating between 10.6 and 12.1 over the last few weeks. This behavior is rare for SS Cyg and has happened only few times since its discovery in 1896. It is particularly important to monitor SS Cyg closely at this time and to record the exact time of the observations. We have prepared a special information package to help observers determine the exact time of their observations, particularly in converting local time to Greenwich Mean Astronomical Time (GMAT). If you need this package, please let us know.

VW Hydri: This bright southern-hemisphere dwarf novae has been of interest to astronomers with observing programs with several satellites, such as the International Ultraviolet Explorer (IUE) and the Hubble Space Telescope (HST) and ORFEUS. HST is scheduled to observe VW Hyi in the coming months during quiescence in order to study the primary component (white dwarf) of this close binary system. Please monitor VW Hyi closely and inform us of its outbursts from now until December 1993. It is particularly important to know if the outburst is a superoutburst (predicted to occur in the coming months).

1908+01 NOVA AQUILAE 1993 [V1419 Aql]

Accompanying are 'b' and 'd' scale charts recently prepared by C. Scovil. Please use the 'd' scale chart as this nova continues to fade. N Aql 93 was reported at magnitudes 12.5 and 12.8 on July 6.1 UT by J. Bortle and C. Scovil, respectively.

FADING OF 1910-33 RY SAGITTARII

Our observers J. Bortle, P. Collins, L. Hiett, D. Overbeek, and D. York have reported that the R Coronae Borealis type variable RY Sgr has started to fade. From June 15 to July 7 it has faded from magnitude 6.5 to 9.1. Its last fading was in 1990. Please monitor RY Sgr closely as it continues to fade and call in your observations to AAVSO Headquarters.

REQUEST TO MONITOR 1834-23 V348 SAGITTARII

This interesting variable, whose light curve resembles that of an R CrB type variable, has been at its minimum state. Astronomers at Louisiana State University are interested to observe it with the IUE satellite when it starts to brighten. Please keep a close eye on it and call in your observations to Headquarters when it is brighter than magnitude 13.0.

As always, thank you very much for your efforts and for your valuable contributions to variable star research.

Clear skies and good observing!


Director

files: N Aql 1993 'b' and 'd' preliminary charts;

---------------------------------------------------‬
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An Alert Notice archive is available at the following URL‭:‬
http‭://‬www.aavso.org/alert-notice-archive

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http‭://‬www.aavso.org/observation-notification#alertnotices

-------------------------------------------------

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          By: Matt Young        
To me type 9's (aka South Hills; see for probably taxonomic changes at http://www.aou.org/committees/nacc/proposals/pending.php ) have a harsh, slightly angry sound..... hence, the lower pitch. Type 9's sound a bit like type 2's but harsher and lower pitched, and the spectrographs can look a lot like a lower pitched type 1 --typical type 1 and 9 have the distinctive initial uptick whereas type 2's don't. The split between type 10 and 4 appears to be real to me given the vocal, behavioral and ecological differences between the two types. Type 10 is a dryer empid like whit, whereas type 4's sound bouncy thus reflecting the down up quality and not just the upward "whit" quality of type 10. Again, to me (differences between vocalizations can be personal) type 3's are very thin, short, weak and squeaky sounding whereas type 5's are more powerful, less squeaky and a tad longer or complex sounding. All the types appear to have conifers they are closely associating with, but not necessarily a single conifer resource.
          Feb. 7: Fieldwork        


Feb. 7
Reading for today:
Ashmore and Sharer, Chapter 5, "Fieldwork," pp. 87-124.
Feder, Chapter 10, "Good Vibrations: Psychics and Dowsers," pp. 261-277.

Fieldwork



ARCHAEOLOGICAL SURVEY

Archaeological survey: Methods archaeologists use to locate sites or acquire data from sites or regions without excavation; observing surface remains and using remote sensing for surface and subsurface remains (ibid. 87). Includes ecological factors. Reveals site numbers/types/form/size/spatial distribution. Not all sites found by survey, some known from history or general knowledge. High quality maps and/or aerial photographs necessary to plot site locations.

Three Basic Methods of Site Discovery:

1. Surface survey: Direct inspection of the terrain while walking at ground level, also called archaeological reconnaissance or reconnaissance survey. Should be done along transects at set intervals based on initial plans, but sometimes field conditions require rethinking the strategy. Oldest and most common survey method.

2. Aerial survey: Survey from above, including aerial photography (high altitude, low altitude, and radio-controlled airplanes with rigged cameras). Low raking light at sunrise and sunset very helpful. Not just regular film, use also infrared, radar, thermography (differential heat on ground). Satellites also used at times; for example Landsat especially useful for roads and regional studies. GIS (Geographical Information Systems) data incorporate multiple sources. All remote sensing techniques require ground truth (or "ground truthing") which simply means physically checking the ground itself to check the features being interpreted in the aerial photos, for example.

3. Subsurface survey: Survey of resources under the surface, either by direct intrusive methods like auguring, coring, or shovel testing (this last is the most common and often done on archaeological reconnaissance if the soil development indicates the likelihood of subsurface deposits; such tests are done on transects, and are often called STPs, or shovel test pits), or remote sensing technologies :
-- magnetometer (for variations in magnetism under ground, as with certain kinds of stone features like walls, or large areas of fired materials like clay in kilns)
-- resistivity detector- measures the differences in subsurface features to conduct electrical current, often because of moisture differences
-- ground-penetrating radar- sends back echoes revealing different densities below surface

These last three technologies require expensive technologies, expert interpretation of the results, and are generally limited in usefulness to larger built subsurface features and remains like walls and floors of structures, and sometimes burials
Not mentioned in the text, archaeologists have also used metal detectors, especially for systematic battlefield surveys; one of the first and most famous examples of this use was at the Little Bighorn Battlefield in Montana.

Once a site is located, it is given a trinomial designation in the U.S. as I described in the last class; other numbering or naming systems are used in other countries. Sites are sometimes also given names, either the historic name if known (Diamond City, near Helena), or as is common in the U.S., a landowner's name (MacHaffie Site, near Helena) or descriptive term (Pictograph Cave, near Billings). Finally, sites locations are established using satellite-based GPS (Global Positioning Systems). This is only a consistent development over the last ten years or so; back when I was doing surveys we used only a topographic map and the UTM system (boy that was fun…you young whippersnappers don't know how easy you got it these days!)

After a site is located, by old-fashioned walking or by one of the remote-sensing based surveys, then it all comes back to walking the ground, mapping the site, and describing what is seen on the surface. The site is mapped, either using traditional mapping technologies such as the transit, or newer technologies such as the laser transit and GPS. Topographic maps and planimetric maps can provide different views of the same site data.

EXCAVATION

Excavation is the principle method that archaeologists use to recover data beneath the surface, and is also sometimes a method of discovery. Subsurface remains are generally the best preserved and least disturbed data (but not always…note that subsurface remains can suffer massive disturbance through rodent burrowing even within recent years… and that some surface remains have laid essentially undisturbed for thousands of years in high remote deserts!)

The two basic goals of excavation:
1. Reveal the three-dimensional patterning/structure in deposition of artifacts, ecofacts, features; evaluation of the provenience and association
2. Assess the functional and temporal significance of the patterning; evaluation of the context
The goal is to reconstruct the past behavior; proper and complete records are VITAL to this effort-- archaeology without proper recordation, notes, maps, etc. is simply LOOTING

For the three-dimensional patterning, it is important to note the distinction between the two horzontal dimensions of a surface (usually synchronous..of the same time period), and the one of depth (usually diachronous…of different periods)

Stratigraphy

Stratification- observed layers of matrix (pl. matrices) and features; each layer is a stratum (strata is plural)

Law of Superposition- geological principle that the sequence of strata from bottom to top reflect the order they were laid in, from earliest at the bottom to the most recent at the top (Please check out the figures in your text for a nice illustration, fig. 5.14 on p. 104 and fig. 5.15 on page 105) Even though there may be cases of reverse stratigraphy that seem to fly in the face of the law of superposition, it still holds true (see fig. 5.15, p. 105).

Stratigraphy- the study and interpretation of stratification. Looking for evidence of redeposition or disturbance--sometimes clarification in complex cases is assisted through conjoining studies ("refitting studies") in which fragments of artifacts and ecofacts from different strata are fitted back together. Stratigraphic evaluation includes both temporal and functional evaluations.

Nonarchitectural features: middens, burials, hearths, quarries
Architectural features: walls, floors, platforms, staircases, roadways

One way to approach stratigraphic evaluation is by using a schematic diagram called a Harris Matrix, a way to abstract the relationships between various stratigraphic elements (see fig. 5-16, p. 108)

Excavation Methods

There are two basic kinds of excavations:

1. (Vertical) - Penetrating excavations- Mainly going deep vertically, to see in cross section the depth, sequencing, and composition of the deposits; test pits, trenches, tunnels.

2. (Horizontal) - Clearing excavations- clears occupation levels horizontally to see the extent of the deposit and the arrangement of features/artifacts/ecofacts of the deposit

Usually both types are excavation are used at a site to fit the different goals of research. Excavation is like taking apart a giant 3D puzzle, and putting it back together on paper/computer…thus the vital importance of complete notes and recordation!

The Toolkit
Take a look at the tools for an excavator's toolkit on p. 111…I will comment for you to note that the "gold standard" for archaeologists is the sharpened Marshalltown triangular trowel (medium size)…it is the identifying badge of the profession of field archaeologist beyond all others! At the minimum you also need a good compass (Brunton is the ideal, but Silva is ok too), folding rule, and tape measure (metric for prehistoric, standard inches and feet for historic). Add a shovel (flat-nose for excavations!) and a good screen, and by gum, those are the essentials.

Micromorphology- The microscopic study of fine deposit residues cut from excavated matrices such as floors.

Provenience Control

Horizontal and vertical provenience must always be the guide and structure for excavation; words fail here…Be sure and look at the excellent diagrams of the grid and excavations on pp. 112-113. It is one of those things easier to show than to tell.

Remember…excavation of a site is destruction of the site. Without proper controls, notes, and research design, there is little noticeable difference between archaeology and looting.
The goal is to take enough proper field notes, scaled drawings, photographs, and standardized info on forms, to be able to reconstruct the site as an ideal.

Field drawings are done as:
1. Sections (side/profile view, or vertical/stratified sections; arifacts in the unit walls, etc.)
2. Plan view (horizontal relationship of features and artifacts/ecofacts)

DATA PROCESSING

Data are collected (artifacts, ecofacts, soil samples from the matrix and features for pollen and other analysis, etc.). There are established systems of collecting, storing, processing, and labeling/storing the data for efficient retrieval later (much like a library or archives). Ecofacts are usually processed by specialists in faunal analysis, floral analysis (including pollen or phytolith analysis), etc. Lithic analysis is also important to understand where the source materials for stone artifacts originated.

CLASSIFICATION

Classification is the process of rearranging or ordering objects into groups on the basis of shared characteristics that archaeologists call attributes.

An attribute is any observable trait that can be defined and isolated. Three basic categories of _directly observable_ attributes are used in archaeology, and the classification will depend on the research questions being asked:

1. Stylistic attributes: color, surface finish/texture, decoration (painted/unpainted), alterations, etc. Stylistic types include pottery classifications based on decoration and finish (ex: the many types of pottery styles of the Pueblo Indians of New Mexico

2. Form attributes: overall 3D form and aspects of the artifact's shape; dimensions (metric attributes)- length, width, thickness, weight. Form types include pottery component shape attributes (ex: thickness of wall, curve of wall, strap or loop handles) or grinding stones cross-sections (ex: round, rectangular, etc.)

3. Technological attributes: raw materials (constituent attributes) and traits relating to the manufacturing process. Technological types include metallurgy processes (ex: different alloys of copper such as brass or bronze) and kiln processes (ex: tempering of sand using sand grit or crushed shell)

Besides classification based on _directly observable_ attributes, artifacts can be classified using _inferred attributes_ measurable only by tests such as spectrographic or chemical analysis, which are not done in the field.

Classification serves 4 basic purposes:

1. Classification divides a mass of undifferentiated data into groups/classes

2. Classification allows the researcher to summarize characteristics of many objects by listing only shared attributes through the definition of …
---------Types: represent clusters of attributes that occur together repeatedly in the same artifacts. For example, Oneota Allamakee Trailed pottery which my tribe the Ioway made in precontact times, is typically distinguished by generally globular form (form attribute), trailed decorations such as chevrons (stylistic attribute), and shell-tempered clay (technological attribute)…other types of precontact pottery in the Midwest may have one or the other of these attributes, but all three attributes taken together make up the Oneota Allamakee Trailed TYPE.

3. Classification defines variability of the artifact, which can lead to further to understanding, as when variability in pottery in some cultures relates to social subgroupings of status or lineage identity.

4. Classification, by ordering and describing types, enables the researcher to suggest a series of relationships among classes.

Ultimately there is no right or wrong classification scheme…it is only a working cognitive tool to get at answering a particular research question. For example, for pottery, if one is studying food storage, one might choose to classify based on form attributes, but if one is studying social identity, one might choose stylistic attributes instead.

It is also possible to relate hierarchies of artifact classifications with hierarchies of social groupings, but depends on the base data.
- Individuals make artifacts based on cultural standards, or norms (attributes).
- Subassemblage -Patterned set of artifacts used by occupational or other groups (hunters, farmers, mothers, etc.).
- Assemblage -Patterned set of subassemblages that represent a community's behavior patterns.
- Archaeological culture -Patterned set of assemblages, sum total of material remains, assumed to represent the culture of a past society


Sites and other subjects also mentioned in this chapter:
Stonehenge (Britain)
Tehaucan Valley (Mexico)
Athens, Rome, Carthage (Mediterranean region)
Troy (Greece); Heinrich Schliemann
Olduvai Gorge (Tanzania); the Leakeys
Lascaux Cave (France)
Tell / tepe - hill/mound (term used in SW Asia/Middle East)
Shahr-I Sokhta (Iran)
Sarepta (Lebanon)
Nile Valley (Egypt)
Sybaris (Greece)
Cahokia (Illinois)
China Lake Valley (California)
Teotihaucan (Mexico)
Pompeii (Italy)
Cerén (El Salvador)
Koobi Fora (Lake Turkana, Kenya)
Lindenmeier Site (Colorado)
Royal "Acropolis", Copan (Honduras)

FEDER

FEDER's chapter on "Good Vibrations: Psychics and Dowsers" is a good match for the Ashmore and Sharer chapter. Feder discusses the real life hard work of finding and excavating sites (which I can vouch for personally), compared to the fantasy of being able to predict where a site is using a dowsing rod or pretending to be able to see into the past and explain what happened at a site.

Claims that are not testable, through excavation, etc., are not science. The evidence of incidents that have been tested does not support the claims of psychic archaeology or dowsing for sites.

On the other hand, Feder is pretty dismissive of water dowsing, but my very down-to-earth Grandpa swore by it, and he and his dad could dowse for water. I do not claim that ability. But then my Grandpa actually tracked down a Will-o-the-Wisp in his youth in the dark brush along the Missouri River in pre-WWII Nebraska, when no one else would go with him because they were afraid of ghosts. He didn't believe in ghosts, as he had never seen one. But the Will-o-the-Wisp he tracked down was actually a piece of phosphorescent wood, its internal gases causing it to float its ghostly way through the dark trees. Grandpa caught that Wisp that dark night…but he didn't crush it like lesser men when confronted with the unknown…he let the Wisp-wood go, content with discovering its mystery, and letting it go on its own mysterious way.

Archaeology is a matter of hard work, though we wish it were otherwise…wishing doesn't make it so.

I believe there is room for science and for mystery in this world. The trick is to not be deceived, and confuse one for the other. Science is an astounding tool to discover empirical truth…but it is a very cold God.

Next Time: Fieldwork
Readings for Next Class on Tuesday:
Reading assignment for next class: Ashmore and Sharer, Chapter 6: “Analyzing the Past,” pp. 125-156.
          The Legend of the Loneliest Whale in the World        

This article is excerpted from “52 Blue,” the newest single from the Atavist. You can purchase the full story from the Atavist’s website. It is also available on Amazon.

Dec. 7, 1992: Whidbey Island, Puget Sound. The World Wars were over. The other wars were over: Korea, Vietnam, the Persian Gulf. The Cold War was finally over, too. The Whidbey Island Naval Air Station remained. So did the Pacific, its waters vast and fathomless beyond an airfield named for an airman whose body was never found: William Ault, who died in the Battle of the Coral Sea.

But at that naval air station, on that day in December, the infinite Pacific appeared as something finite: audio data gathered by a network of hydrophones spread along the ocean floor. These hydrophones had turned the formless it of the ocean and its noises into something measurable: pages of printed graphs rolling out of a spectrograph machine. These hydrophones had been used to monitor Soviet subs until the Cold War ended; after their declassification, the Navy started listening for other noises—other kinds of it—instead.

On Dec. 7, the it was a strange sound. The acoustic technicians thought they knew what it was, but then they realized they didn’t. Petty Officer 2nd Class Velma Ronquille stretched it out on a different spectrogram so she could see it better. She couldn’t quite believe it. It was coming in at 52 hertz.

She beckoned one of the technicians. He needed to come back, she said. He needed to take another look.

The technician came back. He took another look. His name was Joe George.

Petty Officer 2nd Class Ronquille told him, “I think this is a whale.”

Joe thought, Holy cow. It hardly seemed possible. For a blue whale, which is what this one seemed to be, a frequency of 52 hertz was basically off the charts. Blue whales usually come in somewhere between 15 and 20—on the periphery of what the human ear can hear, an almost imperceptible rumble. But here it was, right in front of them, the audio signature of a creature moving through Pacific waters with a singularly high-pitched song.

Whales make calls for a number of reasons—to navigate, to find food, to communicate with each other—and for certain whales, like humpbacks and blues, songs also seem to play a role in sexual selection. Blue males sing louder than females, and the volume of their singing—at more than 180 decibels—makes them the loudest animals in the world. They click and grunt and trill and hum and moan. They sound like foghorns. Their calls can travel thousands of miles through the ocean.

The whale that Joe George and Velma Ronquille heard was an anomaly: His sound patterns were recognizable as those of a blue whale, but his frequency was unheard-of. It was absolutely unprecedented. So they paid attention. They kept tracking him for years, every migration season, as he made his way south from Alaska to Mexico. His path wasn’t unusual, only his song—and the fact that they never detected any other whales around him. He always seemed to be alone.

So this whale was calling out high, and he was calling out to no one—or at least, no one seemed to be answering. The acoustic technicians would come to call him 52 Blue. A scientific report, published 12 years later by researchers at Woods Hole, would describe his case like this:

No other calls with similar characteristics have been identified in the acoustic data from any hydrophone system in the North Pacific basin. Only one series of these 52-Hz calls has been recorded at a time, with no call overlap, suggesting that a single whale produced the calls. … These tracks consistently appeared to be unrelated to the presence or movement of other whale species (blue, fin and humpback) monitored year-round with the same hydrophones.

Much remained unknown, the report confessed, and difficult to explain:

We do not know the species of this whale, whether it was a hybrid or an anomalous whale that we have been tracking. It is perhaps difficult to accept that … there could have been only one of this kind in this large oceanic expanse.

*  *  *

Soon after the report was published, the researchers started getting notes about the whale. They weren’t just typical pieces of professional correspondence. They came, as New York Times reporter Andrew Revkin wrote at the time, “from whale lovers lamenting the notion of a lonely heart of the cetacean world”; others were “from deaf people speculating that the whale might share their disability.”

After Revkin’s story ran that December, headlined “Song of the Sea, a Cappella and Unanswered,” more letters flooded Woods Hole. One marine-mammal researcher quoted in the story, Kate Stafford, may have inadvertently fanned the flames: “He’s saying, ‘Hey, I’m out here,’ ” she told Revkin. “Well, nobody is phoning home.” These letters came from the heartbroken and the deaf, from the lovelorn and the single; the once bitten, twice shy and the twice bitten, forever shy—people who identified with the whale or hurt for him, hurt for whatever set of feelings they’d projected onto him.

A legend was born: the loneliest whale in the world.

In the years since, 52 Blue—or 52 Hertz, as he is known to many of his devotees—has inspired numerous sob-story headlines: not just “The Loneliest Whale in the World” but “The Whale Whose Unique Call Has Stopped Him Finding Love,” “A Lonely Whale’s Unrequited Love Song,” “There Is One Whale That Zero Other Whales Can Hear and It’s Very Alone. It’s the Saddest Thing Ever, and Science Should Try to Talk to It.” There have been imaginative accounts of a solitary bachelor headed down to the Mexican Riviera to troll haplessly for the biggest mammal babes alive, “his musical mating calls ringing for hours through the darkness of the deepest seas, broadcasting a wide repertory of heartfelt tunes.”

A singer in New Mexico, unhappy at his day job in tech, wrote an entire album dedicated to 52; another singer in Michigan wrote a children’s song about the whale’s plight; an artist in upstate New York made a sculpture out of old plastic bottles and called it 52 Hertz. A music producer in Los Angeles started buying cassette tapes at garage sales and recording over them with 52’s song, the song that was quickly becoming a kind of sentimental seismograph suggesting multiple storylines: alienation and determination, autonomy and longing; not only a failure to communicate but also a dogged persistence in the face of this failure.

People have set up Twitter accounts to speak for him, like @52_Hz_Whale, who gets right to the point:

I started seeking out some of the people who’ve become obsessed by this whale over the years: a 19-year-old English major at the University of Toronto who thinks 52 Blue is “the epitome of every person who’s ever felt too weird to love.” A 26-year-old photo editor at the biggest daily tabloid in Poland, who decided to get the outline of 52 Blue tattooed across his back after the end of a six-year relationship:

i was deeply in love. but as it came out she was treating me like a second category person in relationship…i was devastadem mainy becose i have given her everything i could, and i thought she would do the same for me. [Because] of her i lost connection with important friends. View of the wasted time made me sad….Story of 52 hz whale made me happy. For me he is symbol of being alone in a positive way...He is like a steatement, that despite being alone he lives on.

I heard from Shorna, a 22-year-old in Kent, England, who relates to 52 Blue because he reminds her of how difficult it was for her to communicate with anyone after her brother was killed when she was 13: “I felt I couldn’t talk to no one. That no one understood or cared enough.”

I spoke to Sakina, a 28-year-old medical actor living in Michigan, who associates 52 with a different kind of loss—a more spiritual struggle. She says 52 immediately made her think of the prophet Yunus, or Jonas, who was swallowed by a whale. “It makes sense that the loneliest whale feels lonely,” she says. “Because he had a prophet with him, inside of him, and now he doesn’t.”

*  *  *

Hast thou seen the white whale? The hunt for an elusive whale is—of course—the most famous narrative in the history of American literature. The whiteness of Moby Dick is “a dumb blankness, full of meaning,” full of many meanings: divinity or its absence, primal power or its refusal, the possibility of revenge or the possibility of annihilation. “Of all these things the Albino whale was the symbol,” Ishmael explains. “Wonder ye then at the fiery hunt?”

No one has ever conducted a physical search for 52 Blue. An entrepreneur named Dietmar Petutschnig is currently prowling the South Pacific in a small sailboat, but his hunt for the whale seems more metaphorical, a kind of personal branding. Dietmar calls himself skipper and whalefinder and is joined by a co-captain and a chef, along with a little spaniel named Vienna Linz who is billed as security, angler, and crew morale officer. When I spoke to him on the phone while his boat was docked in Vanuatu, Dietmar was reluctant to do an interview but wanted to offer me a job working for him as a freelance editor. “We are still in the middle of our discovery,” he’d written earlier. “We do hope the whale will go out of fashion.”

If anyone actually finds 52, it will probably be Josh Zeman, a filmmaker currently working on a documentary called 52: The Search for the Loneliest Whale in the World. Zeman had been hoping to conduct his actual search this fall, planning to take a research vessel into the Pacific for 50 days, but his funding fell through two weeks after it was announced by his producer, actor Adrian Grenier, at the Cannes Film Festival in May.

Zeman first heard the story of 52 at an artists colony in the summer of 2012, and it struck him immediately. He was in the aftermath of a breakup. He’s been working on the project ever since; he described his relationship to the movie as “Ahabian.” But figuring out how to make the trip work “is fucking complicated,” he told me. The plan was to have a research vessel staffed with five scientists and three crew, using sonar and old migration routes to locate 52. The data was more than a decade old.

One of the themes of Zeman’s film is modern loneliness, that people are particularly responsive to the story of 52 in the digital era—when the Internet promises connectivity but can actually deliver us even deeper into isolation. Ironically enough, the film’s Facebook page has become an effective epicenter for the 52 Hertz community: It’s where people post their responses to the story of the whale, register their sympathy, report their desires. “This story touched me so deeply,” wrote a woman named Pamela. “I wish we could all help and play whale songs for him.” She wanted to know why “we can build laptops and smart phones but we cannot figure out a way to get this whale some companionship?”

Some posts struck a different chord. Catherine was actually a little sick of all the “mawkish sadness” at this “anthropomorphized meme,” and wasn’t afraid to say so, though another user responded immediately to her post. “52 Hertz isn’t a myth or a meme,” she shot back. “He’s real, and I think we’re all damn curious about him.”

Most of the posts converge on two themes: helping 52 and feeling bad for 52. A woman named Denise posted one message—“find 52 hertz”—over and over and over again one morning: at 8:09, 8:11, 8:14, 8:14 (a second time), and 8:16. A woman named Jen wrote, only once: “Just want to give it a hug.”


          Machining and Surface Characteristics of AISI 304L After Electric Discharge Machining for Copper and Graphite Electrodes in Different Dielectric Liquids        

In Electric Discharge Machining (EDM), the thermal energy used for material erosion depends on the intensity of electric sparks, the thermal conductivities of electrode material and the dielectric liquid. In this paper, the effect of EDM on AISI 304L steel is studied using copper and graphite electrodes and distilled water and kerosene oil as dielectric liquids. Material Removal Rates (MRR), Tool Wear Rates (TWR) and surface conditions are calculated for four different combinations with the two electrode materials and the two dielectric liquids. These investigations are carried out at different pulse currents. Machined surfaces are evaluated by morphological studies, energy dispersive spectrographs (EDS) and white layer thickness using Scanning Electron Microscopy (SEM). It is found that a transfer of carbon takes place from the kerosene oil and the graphite electrodes into the machined surface which alters the metallurgical characteristics, depending on the electrical and thermal conductivities of the electrode material and the dielectric liquid.


          MAVEN Gives Unprecedented Ultraviolet View of Mars        
New global images of Mars from the MAVEN mission show the ultraviolet glow from the Martian atmosphere in unprecedented detail, revealing dynamic, previously invisible behavior. They include the first images of "nightglow" that can be used to show how winds circulate at high altitudes. Additionally, dayside ultraviolet imagery from the spacecraft shows how ozone amounts change over the seasons and how afternoon clouds form over giant Martian volcanoes. The images were taken by the MAVEN Imaging UltraViolet Spectrograph (IUVS).
          Special Notice #298: Second set of HST COS CV targets announced        

October 6, 2012:  Following on AAVSO Alert Notice 471 (Gaensicke, Patterson, and Henden, www.aavso.org/aavso-alert-notice-471), the second set of targets the HST COS (Cosmic Origins Spectrograph) will be observing has been announced.
 

Primary Name in VSX RA (2000.0) DEC (2000.0) Type Vmin Vmax
AX For 02 19 28.00 -30 45 45.6 SU 18.5 12.2
1RXS J023238.8-371812 02 32 37.96 -37 17 54.9 WZ 18.8 11
SDSS J001153.08-064739.1 00 11 53.08 -06 47 39.2 DN 17.8 15
HS 2214+2845 22 16 31.19 +29 00 19.7 DN 16.8 12.5
CC Scl 23 15 31.86 -30 48 47.6 SU 17 13.4

Please begin monitoring these cataclysmic variables nightly in preparation for more intensive coverage when the HST observation dates are announced. Instructions are given in Alert Notice 471.

Charts for these targets may be created using VSP (www.aavso.org/vsp).

Please report observations promptly to the AAVSO International Database using the names given in the table (the primary VSX names). If you see a target in outburst, please contact the AAVSO immediately and post a message to the Observations and Campaigns & Observations Reports forum (http://www.aavso.org/forum).

Your observations will be crucial to the success of this campaign. Many thanks!

This AAVSO Special Notice was compiled by Elizabeth O. Waagen.
-------------------------------------------------
SUBMIT OBSERVATIONS TO THE AAVSO

Information on submitting observations to the AAVSO may be found at:
http://www.aavso.org/webobs

SPECIAl NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION

A Special Notice archive is available at the following URL:
http://www.aavso.org/special-notice-archive

Subscribing and Unsubscribing may be done at the following URL:
http://www.aavso.org/observation-notification#specialnotices


          Super-Earth: Newly discovered exoplanet may be most promising yet in search for signs of life        

New Delhi: Earlier, astronomers have discovered a number of nearby exoplanets - or planets outside our solar system - that could harbour life like Proxima b and the seven TRAPPIST-1 planets.

Now, an international team of astronomers has discovered a so-called 'super-Earth' that could contain liquid water, a situation that would make it a very good candidate for harbouring life.

Researchers believe the new exoplanet may be one of the best candidates that may offer the most promising target yet in the search for life beyond the Solar System.

 

Named LHS 1140b, the distant planet is orbiting a nearby star - an M class red dwarf star a little smaller and dimmer than the Sun but the most common type of star in our galaxy.

Super-Earth is a rocky, temperate planet orbiting a red dwarf star, Efe news agency reported.

The super-Earth and its parent star are located in the constellation Cetus, the Whale, 39 light years from the Sun, thus - relatively speaking - putting it in our galactic "neighbourhood," according to Felipe Murgas, the coauthor of the study and a researcher with Spain's Canary Islands Institute of Astrophysics.

The study's main author, Jason Dittmann, with the Harvard-Smithsonian Centre for Astrophysics, said that this is the "most interesting" exoplanet that he's seen in the last decade.

The new planet was discovered thanks to the MEarth-South telescope network devoted exclusively to seeking out exo-planets.

The MEarth-South instruments enabled scientists to measure the planet's diameter and, using the HARPS spectrograph at the LaSilla ESO Observatory in Chile, they also were able to measure its mass, density and orbital period.

According to the measurements, LHS 1140b has a diameter 1.4 times that of Earth and a mass 6.6 times that of our own planet. Early measurement also revealed that the new planet’s orbit is 10 times closer to its star than the Earth is to the Sun.

But more important than that are the climatological conditions, and its orbital distance from its star puts LHS 1140b in the "habitable zone" - thus meaning that the planet's surface temperature allows water to exist in all three of its states: liquid, solid and as a gas.

Whether there is actually water on the planet or not depends on the composition of its atmosphere and other factors, including the presence of a magnetic field, such as the one Earth has, but the most important thing is for the planet to "fulfil the requirements to have water," which means that it must be in its star's habitable zone, Murgas said.

Regarding the age of the planet, the authors of the study said that it probably formed in a manner similar to Earth and its star is probably 5 billion years old, about the same age as the Sun, although the age of M-class stars is hard to determine for a variety of factors, the Spanish researcher added.

In the coming decades, LHS 1140b is sure to be investigated much more intensively, an ongoing project for the powerful next-generation telescopes, including the James Webb instrument and the E-ELT device, which will be installed in Chile and - within a few years - will be able to study the system and try to detect its atmosphere, along with other characteristics.

The planet is designated as a 'super-Earth' because it is 40% larger than our home planet -- 11,000 miles in diameter, 6.6 times the mass of Earth and a much higher density.

The findings have been published in the journal Nature magazine.

(With IANS inputs)

Super-Earth: Newly discovered exoplanet may be most promising yet in search for signs of life
Section: 
Image Caption: 
In this artist tendering provided by M Weiss Harvard-Smithsonian Center for Astrophysics, a newly-discovered rocky exoplanet, LHS 1140b. This planet is located in the liquid water habitable zone surrounding its host star, named LHS 1140b
Yes
News Source: 
Facebook Instant Article: 
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          ASTRONOMIK at the European AstroFest 2013        
ASTRONOMIK will take part at the European AstroFest 2012 held in the Kensington Conference Center in London. At the 8th and 9th of february Gerd will be at the booth of "The Widescreen Center" to answer all your questions. We will also have our large spectrograph with us, so we can demonstrate the effect of all filters directly on the spot! Please bring your filters with you! You may read more about the AstroFest here. If you have any specific needs, please drop an eMail to Gerd until the 5th. of february. (info@gerdneumann.net)
          ASTRONOMIK at the European AstroFest 2012        
ASTRONOMIK will take part at the European AstroFest 2012 held in the Kensington Conference Center in London. At the 10th and 11th of february Gerd will be at the booth of "The Widescreen Center" to answer all your questions. We will also have our new digital mobile spectrograph with us, so we can measure all your filters directly on the spot! Please bring your filters with you! You may read more about the AstroFest here. If you have any specific needs, please drop an eMail to Gerd until the 3rd of february. (info@gerdneumann.net)
          Seeing double        

Approximately 95 million light-years away, in the southern constellation of Octans (The Octant), lies NGC 7098 — an intriguing spiral galaxy with numerous sets of double features. The first of NGC 7098’s double features is a duo of distinct ring-like structures that loop around the galaxy’s hazy heart. These are NGC 7098’s spiral arms, which have wound themselves around the galaxy’s luminous core. This central region hosts a second double feature: a double bar.

NGC 7098 has also developed features known as ansae, visible as small, bright streaks at each end of the central region. Ansae are visible areas of overdensity — they commonly take looping, linear, or circular shapes, and can be found at the extremities of planetary ring systems, in nebulous clouds, and, as is the case with NGC 7098, in parts of galaxies that are packed to the brim with stars.

This image is formed from data gathered by the FOcal Reducer and low dispersion Spectrograph (FORS) instrument, installed on ESO’s Very Large Telescope at Paranal Observatory. An array of distant galaxies are also visible throughout the frame, the most prominent being the small, edge-on, spiral galaxy visible to the left of NGC 7098, known as ESO 048-G007.


          Guarding the galactic heart        

Like sentries guarding the heart of our home galaxy, the ESO 3.6-metre telescope and the Coudé Auxiliary Telescope stand tall in this stunning ultra high definition photograph from the La Silla Observatory, situated in the southern outskirts of the Chilean Atacama Desert.

Since its inauguration in 1976, the ESO 3.6-metre telescope has undergone various upgrades, including the installation of a new secondary mirror that has allowed the telescope to remain as efficient and productive as ever. Since 2008, the telescope has housed the HARPS spectrograph, the most precise exoplanet hunter in the world. HARPS, the High Accuracy Radial velocity Planet Searcher, is the most successful finder of low-mass exoplanets to date.

The now-decommissioned 1.4-metre Coudé Auxiliary Telescope (CAT) is housed in the smaller dome to the right of the 3.6-metre telescope. When active, the telescope fed the 3.6-metre’s Coudé Echelle Spectrometer through a light tunnel, which can be seen connecting the two facilities in this photograph. Fully computer controlled, CAT was used for many different types of astronomical observations, including measuring the ages of ancient stars.

Positioned 2400 metres above sea level and located far from sources of light pollution, the ESO 3.6-metre telescope experiences excellent observing conditions, as does the observatory’s entire family of telescopes. This family includes the New Technology Telescope (NTT), the MPG/ESO 2.2-metre telescope, and a selection of national telescopes.


          The new Hubble servicing mission        

NASA has decided to launch a Space Shuttle mission in 2008 to repair and upgrade the NASA/ESA observatory. This servicing mission will ensure that Hubble can function for perhaps as many as another ten years and will increase its scientific capabilities in some key areas. Two new scientific instruments will be installed as part of the upgrade: the Cosmic Origin Spectrograph and the Wide Field Camera 3. Both will improve Hubble's potential for discovery. Around the same time of this mission, ESA will launch Herschel, the Orbiting Telescope with the largest mirror ever deployed in space. Herschel will complement Hubble in the infrared part of the spectrum.

ESApod video programme

          Optics:Introduction and History        
What is optics?
Optics is the science which deals with the science of study of light , the properties of light , it's transmission and behaviour. optics involves the relationship of light of with matter and their interaction. It has found its use even in ophthalmology and spectrography , while rapidly finding its application in various fields.

History of Optics

The word optics has been derived from the Greek word Ï„α ὀπτικά (ta optiká) which means the visual.It was the Greek and Indian civilizations that made great advances in optics, though the development of the first lens was by the Assyrians , which is modern day Iraq was the first to make the lens.These lenses were made of Quartz and were used as burning glasses.They were housed in the palace of Nimrud thus giving their name Nimrud Lens.Light was considered as one of the vital elements which is required for life by the Greeks.Euclid, around 300 BC compiled his book known as optics which dealt with the geometry and behaviour of light.It dealt with vision and how it is perceived.He thus put forth :

1.Lines (or visual rays) can be drawn in a straight line to the object.
2.Those lines falling upon an object form a cone.
3.Those things upon which the lines fall are seen.
4.Those things seen under a larger angle appear larger.
5.Those things seen by a higher ray, appear higher.
6.Right and left rays appear right and left.
7.Things seen within several angles appear clearer.

Even the Hero of Alexandria in his famous catoptrics has dealt with various factors of optics.While in the Islamic countries, al-kindi and Ibn stahl put forth a number of axioms related to optics.





          Technology of UFOs with Robert Schroeder        
People are often skeptical about the UFO phenomenon but phenomenon but they shouldn't be. At least a subset of UFO reports of around 5 percent are from credible witnesses and frequently backed by hard data such as radar tapes or gun camera film. For example astronauts Gordon Cooper and Buzz Aldrin as well as Harvard astronomer Clyde Tombaugh
have all publicly described their UFO sightings. But the interesting thing is that we may be on the threshold of understanding the technology of UFOs. In a nutshell it was once thought that the idea of extra dimensions was strictly the domain of science fiction. That has all changed in the last several decades as physicists appear to be closing in on a final ''theory of everything'' which suggests we may live in an eleven dimensional universe. These cutting edge theories are now being tested at the Large Hadron Collider particle accelerator in Geneva, Switzerland. Among the theories being tested is one called Warped Geometry by a Harvard physicist which may allow for fast interstellar travel in the extra dimensions. Spectrographic data from actual UFO sightings would confirm if these craft are using technology we are now on the cusp of unraveling.

           2003 North American interagency intercomparison of ultraviolet spectroradiometers: scanning and spectrograph instruments         
Article Lantz, K. , Disterhoft, P. , Slusser, J. , Gao, W. , Berndt, J. , Bernhard, G. , Bloms, S. , Booth, R. , Ehramjian, J. , Harrison, L. , Janson, G. , Johnston, P. , Kiedron, P. , McKenzie, R. , Kimlin, M. , Neale, P. , O'Neill, M. , Quang, V. , Seckmeyer, G. , Taylor, T. , Wuttke, S. and Michalsky, J. (2008) 2003 North American interagency intercomparison of ultraviolet spectroradiometers: scanning and spectrograph instruments , Journal of Applied Remote Sensing, 2, 023547, 2 . doi:10.1117/1.3040299 , hdl:10013/epic.31887
          An 'absolutely phenomenal' discovery hints 4 Earth-size planets may orbit the closest sun to our own        

exoplanets extrasolar planets earth like artist illustration shutterstock_600502655

  • Astronomers have detected what may be four roughly Earth-size planets orbiting Tau Ceti, the nearest sun-like star.
  • Two of the worlds appear to orbit within Tau Ceti's habitable zone, though a cloud of debris and asteroids may pose a threat to any life on them.
  • If the result is confirmed, independent astronomers say it would be "astonishing.

Astronomers may have just hit a crucial milestone in the search for other Earth-like planets. Scientists from the University of Hertfordshire and University of California, Santa Cruz announced they've discovered four planets orbiting a nearby, sun-like star — two of which may be habitable.

Researchers have turned up thousands of planet candidates in recent years, about 10 of which may be small, rocky, and habitable like the Earth. You'd think most of these worlds would orbit suns like ours, but that's not the case, since such stars are so big and bright that they easily drown out the faint signals of tiny planets.

That's why the new discovery of four roughly Earth-size worlds  — some 12 light-years away from our solar system — is all the more exciting.

"If true this discovery is absolutely phenomenal — that one of our nearest neighboring sun-like stars might have rocky worlds," Sara Seager, a planetary scientist at MIT who wasn't involved in the research, told Business Insider in an email.

Worlds in the closest sun-like solar system

The suspected planets all orbit Tau Ceti, a star located 11.9 light-years away from us, according to a forthcoming study in The Astrophysical Journal. (You can read a pre-print version of the paper on arXiv.)

The star is about three-quarters the mass of the sun, but its brightness and color are very sun-like. It's the closest sun-like star to Earth.

The planets' sizes aren't known yet, but they're estimated to have about 1.7 times the Earth's mass. That would make them the smallest planets ever detected around a distant sun-like star, according to a press release emailed by the University of Hertfordshire.

Two of the four worlds orbit in a searing-hot zone close to Tau Ceti. The other two "super-Earths" seem to orbit within a "Goldilocks" habitable zone, where water on the surface can be liquid (rather than frozen solid or boiled away), according to a press release by the University of California Santa Cruz.

tau ceti solar system habitable zone planets university hertfordshire

Two things make this particular discovery stunning to astronomers like Seager.

First, our solar system is the only place we know where life exists, which means that sun-like stars may be the best places to look for life (though there is some debate about whether smaller, cooler red dwarf stars could be better to explore).

Second, it's incredibly difficult to spy a relatively tiny planet in the figurative shadow of a sun-like star.

"Earth is so small in mass compared to its host sun-like star that finding the signal amidst the noise is really like finding the proverbial needle in a haystack," Seager added. "The authors have come up with a special technique to get rid of the noise to find the signal. It's always a tricky situation to look for very weak signals."

Scouting for tiny wobbles

Most planets are detected by a "wobble method," where a planet slightly jerks around its star.

Such wobbles or wiggles (technically called Doppler shifts) come from planets sharing a center of gravity that doesn't reside precisely in the middle of a star. Jupiter, for example, actually orbits a spot some 30,000 miles above the sun's surface — and not in a perfect circle.

jupiter sun barycenter center of mass distance nasa business insider labeled

This wobbling causes slight speeding up and slowing down of a star as a planet orbits it, leaving an imprint on the light the star emits.

In their new study, the team detected variations on the order of 30 centimeters per second — a gap of about 2/3 of a mile per hour. Astronomers think they'll need a sensitivity three times better (about 0.2 mph) to reliably detect Earth analogs around sun-like stars.

"We're getting tantalizingly close to observing the correct limits required for detecting Earth-like planets," Fabo Feng, an astrophysicist at the University of Hertfordshire who led the research, said in the press release. "Our detection of such weak wobbles is a milestone in the search for Earth analogs and the understanding of the Earth's habitability through comparison with these [new planets]."

telescopes hawaii w m keck observatoryTo find the planets, it took Feng and his colleagues four years to sift through, analyze, and model the data gathered by two telescope instruments: the European Southern Observatory's HARPS spectrograph in Chile and the W.M. Keck Observatory's HiRes instrument in Hawaii.

Seager emphasized that "it would take a long time" for other astronomers to replicate and verify the discovery.

"There is no sugar-coating how hard it is to find an Earth-mass planet signal in a sun-like star, due to star noise and instrument noise," Seager said.

Two hits to habitability

Small, rocky worlds in a habitable zone aren't necessarily cozy environments for life.

One possible problem with Tau Ceti's two habitable-zone-worlds is their unknown size.

"They surely don't conclude that the four planets are Earth-sized, because the method they used to detect them provides no information on their sizes," Michaël Gillon, an astronomer at the Université de Liège who wasn't involved in the study, told Business Insider in an email. (Gillon helped with the discovery of the seven Earth-size planets orbiting the TRAPPIST-1 star system.)

"All they can say is that each planet is more massive than X Earth-masses," he said. In the case of Tau Ceti, this lower limit seems to be about 1.7 times as hefty as Earth, and it's uncertain if complex life could thrive on a planet like this.

Another problem is the debris.

dust asteroids disk planets star solar system nasa PIA06939 1920x1200

In fact, estimates suggests that the Tau Ceti system has roughly 10 times the mass of asteroids (and dust) than our solar system.

That's not a great sign, because asteroid impacts are known to wipe out vast numbers of species.

Still, Seager characterized the result as "astonishing." Once the planets are confirmed by other researchers, she added, it could be "a tremendous milestone en route to finding our Earth twin."

Join the conversation about this story »

NOW WATCH: Stephen Hawking warned us about contacting aliens, but this astronomer says it's 'too late'


          Alert Notice 247: 1224-22 Supernova 1998bn in NGC 4462        

THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
INTERNET:  aavso@aavso.org
Tel. 617-354-0484       FAX 617-354-0665

AAVSO ALERT NOTICE 247 (April 29, 1998)

1224-22 SUPERNOVA 1998bn IN NGC 4462

We have been informed by the Central Bureau for Astronomical Telegrams (IAU
Circular 6886
) that W.D. Li, M. Modjaz, R.R. Treffers, and A.V. Filippenko,
University of California at Berkeley, report the discovery of a supernova
made during the course of the Lick Observatory Supernova Search, using the
0.8-m Katzman Automatic Imaging Telescope.  Unfiltered CCD images obtained
on April 17.3 UT and April 27.3 UT showed the supernova at magnitude
approximately 17.4 and 13.7, respectively.  No star was seen at the position
of SN 1998bn on the Digital Sky Survey.

SN 1998bn is located at:

    R.A. = 12h 29m 18.88s    Decl. = -23 degrees 09' 49.2"  (equinox 2000.0)

and is about 32.3" west and 9.7" north of the nucleus of NGC 4462.

Spectroscopic confirmation was obtained by F. Patat, European Southern
Observatory, and M. Maia, Observatorio Nacional, Rio de Janeiro (IAU Circular
6888
), using the ESO 1.5-m telescope (+ Boller & Chivens spectrograph).  They
report that full reduction of their CCD spectrogram taken on April 28.10 UT
indicates that SN 1998bn is a Type Ia supernova about 4 days before maximum,
very similar to SN 1994D.

Observations of SN 1998bn submitted to the AAVSO include: Apr. 28.6611 UT,
13.9, R. Stubbings, Drouin, Victoria, Australia (vsnet sequence); 28.714,
13.4:, B. Monard, Pretoria, S. Africa (EX Hya sequence); 28.749, 13.5:, Monard
(Monard sequence); 28.795, 13.5:, Monard (Monard sequence).

Accompanying is an AAVSO 'e' scale Supernova Search Preliminary chart of
NGC 4462, prepared by C. Scovil and showing the location of SN 1998bn.
Please use this chart to observe the supernova, and report your observations
of 1224-22 SN 1998bn to AAVSO Headquarters, making sure you indicate which
comparison stars you used.

Congratulations to the Lick Observatory Supernova Search team on their
latest discovery!

CHARTS AVAILABLE ON AAVSO FTP SITE

Chart links obsolete, 11/2013: Create charts using VSP at http://www.aavso.org/vsp

Electronic copies of the AAVSO chart of SN 1998bn in NGC 4462 mentioned in
this Alert Notice are available from our FTP site:

            ftp.aavso.org (198.116.78.2), in /pub/alerts/alert247/
or
          ftp.aavso.org (198.116.78.2), in /pub/charts/crv/sn1998bn/

The chart may also be accessed through our Web site at the following address:

                         http://www.aavso.org

The answering machine at AAVSO Headquarters is on nights and weekends for your
convenience.  Please call our charge-free number (800-642-3883) to report your
observations.  We also encourage observers to send observations by fax to
617-354-0665 or by e-mail through the Internet to observations@aavso.org.

Many thanks for your valuable astronomical contributions and your efforts.

Good observing!

Elizabeth O. Waagen, Senior Technical Assistant
on behalf of
Janet A. Mattei, Director

---------------------------------------------------‬
SUBMIT OBSERVATIONS TO THE AAVSO

Information on submitting observations to the AAVSO may be found at‭:‬
http‭://‬www.aavso.org/webobs

ALERT NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION

An Alert Notice archive is available at the following URL‭:‬
http‭://‬www.aavso.org/alert-notice-archive

Subscribing and Unsubscribing may be done at the following URL‭:‬
http‭://‬www.aavso.org/observation-notification#alertnotices

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Please support the AAVSO and its mission -- Join or donate today:
http://www.aavso.org/apps/donate/


           Spectrography of Disputed Speech Samples by Peripheral Human Hearing Modelling         
Howard, DM, Hirson, A, Brookes, TS and Tyrrell, AM (1995) Spectrography of Disputed Speech Samples by Peripheral Human Hearing Modelling Forensic Linguistics, 2 (1). pp. 22-38.
          An 'absolutely phenomenal' discovery hints 4 Earth-size planets may orbit the closest sun to our own        

exoplanets extrasolar planets earth like artist illustration shutterstock_600502655

  • Astronomers have detected what may be four roughly Earth-size planets orbiting Tau Ceti, the nearest sun-like star.
  • Two of the worlds appear to orbit within Tau Ceti's habitable zone, though a cloud of debris and asteroids may pose a threat to any life on them.
  • If the result is confirmed, independent astronomers say it would be "astonishing.

Astronomers may have just hit a crucial milestone in the search for other Earth-like planets. Scientists from the University of Hertfordshire and University of California, Santa Cruz announced they've discovered four planets orbiting a nearby, sun-like star — two of which may be habitable.

Researchers have turned up thousands of planet candidates in recent years, about 10 of which may be small, rocky, and habitable like the Earth. You'd think most of these worlds would orbit suns like ours, but that's not the case, since such stars are so big and bright that they easily drown out the faint signals of tiny planets.

That's why the new discovery of four roughly Earth-size worlds  — some 12 light-years away from our solar system — is all the more exciting.

"If true this discovery is absolutely phenomenal — that one of our nearest neighboring sun-like stars might have rocky worlds," Sara Seager, a planetary scientist at MIT who wasn't involved in the research, told Business Insider in an email.

Worlds in the closest sun-like solar system

The suspected planets all orbit Tau Ceti, a star located 11.9 light-years away from us, according to a forthcoming study in The Astrophysical Journal. (You can read a pre-print version of the paper on arXiv.)

The star is about three-quarters the mass of the sun, but its brightness and color are very sun-like. It's the closest sun-like star to Earth.

The planets' sizes aren't known yet, but they're estimated to have about 1.7 times the Earth's mass. That would make them the smallest planets ever detected around a distant sun-like star, according to a press release emailed by the University of Hertfordshire.

Two of the four worlds orbit in a searing-hot zone close to Tau Ceti. The other two "super-Earths" seem to orbit within a "Goldilocks" habitable zone, where water on the surface can be liquid (rather than frozen solid or boiled away), according to a press release by the University of California Santa Cruz.

tau ceti solar system habitable zone planets university hertfordshire

Two things make this particular discovery stunning to astronomers like Seager.

First, our solar system is the only place we know where life exists, which means that sun-like stars may be the best places to look for life (though there is some debate about whether smaller, cooler red dwarf stars could be better to explore).

Second, it's incredibly difficult to spy a relatively tiny planet in the figurative shadow of a sun-like star.

"Earth is so small in mass compared to its host sun-like star that finding the signal amidst the noise is really like finding the proverbial needle in a haystack," Seager added. "The authors have come up with a special technique to get rid of the noise to find the signal. It's always a tricky situation to look for very weak signals."

Scouting for tiny wobbles

Most planets are detected by a "wobble method," where a planet slightly jerks around its star.

Such wobbles or wiggles (technically called Doppler shifts) come from planets sharing a center of gravity that doesn't reside precisely in the middle of a star. Jupiter, for example, actually orbits a spot some 30,000 miles above the sun's surface — and not in a perfect circle.

jupiter sun barycenter center of mass distance nasa business insider labeled

This wobbling causes slight speeding up and slowing down of a star as a planet orbits it, leaving an imprint on the light the star emits.

In their new study, the team detected variations on the order of 30 centimeters per second — a gap of about 2/3 of a mile per hour. Astronomers think they'll need a sensitivity three times better (about 0.2 mph) to reliably detect Earth analogs around sun-like stars.

"We're getting tantalizingly close to observing the correct limits required for detecting Earth-like planets," Fabo Feng, an astrophysicist at the University of Hertfordshire who led the research, said in the press release. "Our detection of such weak wobbles is a milestone in the search for Earth analogs and the understanding of the Earth's habitability through comparison with these [new planets]."

telescopes hawaii w m keck observatoryTo find the planets, it took Feng and his colleagues four years to sift through, analyze, and model the data gathered by two telescope instruments: the European Southern Observatory's HARPS spectrograph in Chile and the W.M. Keck Observatory's HiRes instrument in Hawaii.

Seager emphasized that "it would take a long time" for other astronomers to replicate and verify the discovery.

"There is no sugar-coating how hard it is to find an Earth-mass planet signal in a sun-like star, due to star noise and instrument noise," Seager said.

Two hits to habitability

Small, rocky worlds in a habitable zone aren't necessarily cozy environments for life.

One possible problem with Tau Ceti's two habitable-zone-worlds is their unknown size.

"They surely don't conclude that the four planets are Earth-sized, because the method they used to detect them provides no information on their sizes," Michaël Gillon, an astronomer at the Université de Liège who wasn't involved in the study, told Business Insider in an email. (Gillon helped with the discovery of the seven Earth-size planets orbiting the TRAPPIST-1 star system.)

"All they can say is that each planet is more massive than X Earth-masses," he said. In the case of Tau Ceti, this lower limit seems to be about 1.7 times as hefty as Earth, and it's uncertain if complex life could thrive on a planet like this.

Another problem is the debris.

dust asteroids disk planets star solar system nasa PIA06939 1920x1200

In fact, estimates suggests that the Tau Ceti system has roughly 10 times the mass of asteroids (and dust) than our solar system.

That's not a great sign, because asteroid impacts are known to wipe out vast numbers of species.

Still, Seager characterized the result as "astonishing." Once the planets are confirmed by other researchers, she added, it could be "a tremendous milestone en route to finding our Earth twin."

SEE ALSO: 25 photos that prove you're a stowaway on a giant spaceship

DON'T MISS: Why stars that are very different from the sun may be the best place to look for alien life

Join the conversation about this story »

NOW WATCH: Stephen Hawking warned us about contacting aliens, but this astronomer says it's 'too late'


          An 'absolutely phenomenal' discovery hints 4 Earth-size planets may orbit the closest sun to our own        

exoplanets extrasolar planets earth like artist illustration shutterstock_600502655

  • Astronomers have detected what may be four roughly Earth-size planets orbiting Tau Ceti, the nearest sun-like star.
  • Two of the worlds appear to orbit within Tau Ceti's habitable zone, though a cloud of debris and asteroids may pose a threat to any life on them.
  • If the result is confirmed, independent astronomers say it would be "astonishing.

Astronomers may have just hit a crucial milestone in the search for other Earth-like planets. Scientists from the University of Hertfordshire and University of California, Santa Cruz announced they've discovered four planets orbiting a nearby, sun-like star — two of which may be habitable.

Researchers have turned up thousands of planet candidates in recent years, about 10 of which may be small, rocky, and habitable like the Earth. You'd think most of these worlds would orbit suns like ours, but that's not the case, since such stars are so big and bright that they easily drown out the faint signals of tiny planets.

That's why the new discovery of four roughly Earth-size worlds  — some 12 light-years away from our solar system — is all the more exciting.

"If true this discovery is absolutely phenomenal — that one of our nearest neighboring sun-like stars might have rocky worlds," Sara Seager, a planetary scientist at MIT who wasn't involved in the research, told Business Insider in an email.

Worlds in the closest sun-like solar system

The suspected planets all orbit Tau Ceti, a star located 11.9 light-years away from us, according to a forthcoming study in The Astrophysical Journal. (You can read a pre-print version of the paper on arXiv.)

The star is about three-quarters the mass of the sun, but its brightness and color are very sun-like. It's the closest sun-like star to Earth.

The planets' sizes aren't known yet, but they're estimated to have about 1.7 times the Earth's mass. That would make them the smallest planets ever detected around a distant sun-like star, according to a press release emailed by the University of Hertfordshire.

Two of the four worlds orbit in a searing-hot zone close to Tau Ceti. The other two "super-Earths" seem to orbit within a "Goldilocks" habitable zone, where water on the surface can be liquid (rather than frozen solid or boiled away), according to a press release by the University of California Santa Cruz.

tau ceti solar system habitable zone planets university hertfordshire

Two things make this particular discovery stunning to astronomers like Seager.

First, our solar system is the only place we know where life exists, which means that sun-like stars may be the best places to look for life (though there is some debate about whether smaller, cooler red dwarf stars could be better to explore).

Second, it's incredibly difficult to spy a relatively tiny planet in the figurative shadow of a sun-like star.

"Earth is so small in mass compared to its host sun-like star that finding the signal amidst the noise is really like finding the proverbial needle in a haystack," Seager added. "The authors have come up with a special technique to get rid of the noise to find the signal. It's always a tricky situation to look for very weak signals."

Scouting for tiny wobbles

Most planets are detected by a "wobble method," where a planet slightly jerks around its star.

Such wobbles or wiggles (technically called Doppler shifts) come from planets sharing a center of gravity that doesn't reside precisely in the middle of a star. Jupiter, for example, actually orbits a spot some 30,000 miles above the sun's surface — and not in a perfect circle.

jupiter sun barycenter center of mass distance nasa business insider labeled

This wobbling causes slight speeding up and slowing down of a star as a planet orbits it, leaving an imprint on the light the star emits.

In their new study, the team detected variations on the order of 30 centimeters per second — a gap of about 2/3 of a mile per hour. Astronomers think they'll need a sensitivity three times better (about 0.2 mph) to reliably detect Earth analogs around sun-like stars.

"We're getting tantalizingly close to observing the correct limits required for detecting Earth-like planets," Fabo Feng, an astrophysicist at the University of Hertfordshire who led the research, said in the press release. "Our detection of such weak wobbles is a milestone in the search for Earth analogs and the understanding of the Earth's habitability through comparison with these [new planets]."

telescopes hawaii w m keck observatoryTo find the planets, it took Feng and his colleagues four years to sift through, analyze, and model the data gathered by two telescope instruments: the European Southern Observatory's HARPS spectrograph in Chile and the W.M. Keck Observatory's HiRes instrument in Hawaii.

Seager emphasized that "it would take a long time" for other astronomers to replicate and verify the discovery.

"There is no sugar-coating how hard it is to find an Earth-mass planet signal in a sun-like star, due to star noise and instrument noise," Seager said.

Two hits to habitability

Small, rocky worlds in a habitable zone aren't necessarily cozy environments for life.

One possible problem with Tau Ceti's two habitable-zone-worlds is their unknown size.

"They surely don't conclude that the four planets are Earth-sized, because the method they used to detect them provides no information on their sizes," Michaël Gillon, an astronomer at the Université de Liège who wasn't involved in the study, told Business Insider in an email. (Gillon helped with the discovery of the seven Earth-size planets orbiting the TRAPPIST-1 star system.)

"All they can say is that each planet is more massive than X Earth-masses," he said. In the case of Tau Ceti, this lower limit seems to be about 1.7 times as hefty as Earth, and it's uncertain if complex life could thrive on a planet like this.

Another problem is the debris.

dust asteroids disk planets star solar system nasa PIA06939 1920x1200

In fact, estimates suggests that the Tau Ceti system has roughly 10 times the mass of asteroids (and dust) than our solar system.

That's not a great sign, because asteroid impacts are known to wipe out vast numbers of species.

Still, Seager characterized the result as "astonishing." Once the planets are confirmed by other researchers, she added, it could be "a tremendous milestone en route to finding our Earth twin."

SEE ALSO: 25 photos that prove you're a stowaway on a giant spaceship

DON'T MISS: Why stars that are very different from the sun may be the best place to look for alien life

Join the conversation about this story »

NOW WATCH: Stephen Hawking warned us about contacting aliens, but this astronomer says it's 'too late'


          Knight Rider’s 15-Second Clip Released        


Finally the long wait is over. NBC network in America has released a 15 second clip of the upcoming remake of the 1980’s iconic television show Knight Rider. The 540 horsepower Ford Mustang Shelby GT500KR is officially the new KITT (Knight Industries Three Thousand) with the artificial intelligence voice provided by Will Arnett. NBC network will air the Knight Rider TV movie at 9pm ET on February 17, 2008 Sunday.

Knight Industries Three Thousand: 2008 Ford Mustang Shelby GT500KR

Vehicle Type: Front engine, on-demand all-wheel drive, two-door coupe
Engine Type: Aluminum block/titanium heads 5.4-liter V8 internal combustion with Whipple supercharger and Knight Industries liquid air cycle auxiliary turbine engine. 540 hp in Hero mode. Power output can’t be measured in Attack mode.
Transmission: Continuously variable transmission with infinite power band
Price New: $45.6 million, as tested
Acceleration: 0 to 60 mph: 1.77 seconds. Standing quarter mile: 3.87 seconds
Braking (300 to 0 mph): 12 ft.
Fuel Economy: Not testable

Special Features as KITT:

Knight Industries 2000 microprocessor: Version 2.3
Auto Cruise
Auto Pursuit
Auto Collision Avoidance
Voice Interaction
Emergency Eject
Audio/Video In-Dash Functions
Radar
Sonar
X-Ray
Autopilot
Voice Analyzer
Infrared Tracking Scope
Range: 20 miles
Pyroclastic Lamination
Blood Analyzer
Microwave Jammer
Interior Oxygenator
Rocket Boosters
Smokescreen
Olfactory Detector
Spectrograph
Electromagnetic Field Generator
Microwave Ignition Sensor
Aquatic Synthesizer
Electronic Field Disrupter
Ultra Magnesium Charges
Ultraphonic Chemical Analyzer
Graphic Translator
Anamorphic Equalizer
DNA Analysis Equipment
Mass Spectrometer
Targeted Electromagnetic Pulse
Military-Grade GPS
Heated Seats
3D Heads-Up Display
Laser Weapons System
Holographic Projection
Keyless Entry and Ignition
Personal Safety System
Nanotech Cloaking
360-Degree Video Surveillance
Laser-Guided Missile Defense
Mini-KITT Reconnaissance Drone
24-Hour Roadside Assistance
1000-Watt Quadraphonic Stereo System
In-Seat Medical Diagnosis
Biometric Analysis