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January 2013 HAD Meeting Abstracts
All sessions and meetings in the Long Beach Convention and Entertainment Center.
HAD I Special: Making Astronomy Public, Los Angeles Style
Session #90: Sunday, 6 Jan 2013, 1:30–3:30 p.m. Room 103B
Session Chair: David DeVorkin, Smithsonian Institution.
Description: This 120 minute special session will explore aspects of popular astronomy in the Los Angeles area over the past 150 years that stimulated public awareness and interest in astronomy. Topics include: (1) organized amateur astronomy in Los Angeles, (2) the growth of the amateur telescope industry in Los Angeles, (3) L.A. style astronomical evangelists, (4) the forces that created and shaped the Griffith Observatory and the Mt. Lowe Observatory, (5) the influence of astronomers ranging from George Ellery Hale to Frederick C. Leonard to Tommy Cragg in all these aspects of public astronomy in the Los Angeles area, (6) if there is a distinguishable "L.A. style" to public astronomy in Los Angeles.
Peter Abrahams, Thomas Williams, and David DeVorkin, Session Organizers
1:30 1. Creating Griffith Observatory
Anthony Cook, Griffith Observatory.
Griffith Observatory has been the iconic symbol of the sky for southern California since it began its public mission on May 15, 1935. While the Observatory is widely known as being the gift of Col. Griffith J. Griffith (1850-1919), the story of how Griffith’s gift became reality involves many of the people better known for other contributions that made Los Angeles area an important center of astrophysics in the 20th century. Griffith began drawing up his plans for an observatory and science museum for the people of Los Angeles after looking at Saturn through the newly completed 60-inch reflector on Mt. Wilson. He realized the social impact that viewing the heavens could have if made freely available, and discussing the idea of a public observatory with Mt. Wilson Observatory’s founder, George Ellery Hale, and Director, Walter Adams. This resulted, in 1916, in a will specifying many of the features of Griffith Observatory, and establishing a committee managed trust fund to build it. Astronomy popularizer Mars Baumgardt convinced the committee at the Zeiss Planetarium projector would be appropriate for Griffith’s project after the planetarium was introduced in Germany in 1923. In 1930, the trust committee judged funds to be sufficient to start work on creating Griffith Observatory, and letters from the Committee requesting help in realizing the project were sent to Hale, Adams, Robert Millikan, and other area experts then engaged in creating the 200-inch telescope eventually destined for Palomar Mountain. A Scientific Advisory Committee, headed by Millikan, recommended that Caltech physicist Edward Kurth be put in charge of building and exhibit design. Kurth, in turn, sought help from artist Russell Porter. The architecture firm of John C. Austin and Fredrick Ashley was selected to design the project, and they adopted the designs of Porter and Kurth. Philip Fox of the Adler Planetarium was enlisted to manage the completion of the Observatory and become its temporary Director.
1:50 2. The Early Years of Amateur Astronomy in Los Angeles—Conflicts and Contradictions
Thomas R. Williams, AAVSO.
Astronomy had an active audience in Los Angeles from the latter years of the nineteenth century on. However, it is surprising that organized avocational astronomy did not really flower until the promotion of amateur telescope making as a hobby beginning in the mid-1920s. Even though astronomy burgeoned as a local industry with the Mount Wilson Astronomical Observatory visible from much of the LA Basin on most days, astronomers from the observatory providing informative talks to local groups, and the Griffith Observatory actively promoting interest in astronomy as well as science more generally, interest in telescope making and recreational observing continued to dominate the activities of Los Angeles amateurs for the first twenty-five years of the local society’s existence. Even the later active membership of outstanding scientific contributors like Tom Cave and Tom Cragg, and the participation of astronomy students from UCLA and Caltech like George Herbig, yielded little change in direction over this period.
2:10 3. The Space-Age Legacy of Telescope Designer George A. Carroll
John W. Briggs, HUT Observatory.
Remembered particularly as a founding member of Stony Ridge Observatory near Mount Wilson, George A. Carroll (1902-1987) was legendary in the Southern California telescope making community. In Texas at the age of sixteen, Carroll built and flew his own aircraft, becoming one of the youngest aviators in the country. He eventually became an employee of Lockheed’s “Skunk Works” in Burbank. His earliest known commercial telescopes were high-end amateur instruments built by R.R. Cook. As described in a brochure describing his later telescope work, he had “experience in so many branches of technology that it is unbelievable.” By the time Carroll's designs were built by Thomas Tool & Die in Sun Valley, his telescopes were well known in the solar community and in use at National Solar Observatory, Caltech, and at many other domestic and international research institutions. Among the most remarkable were large solar spars for Lockheed Solar Observatory in California and Ottawa River Solar Observatory in Canada. His instrumentation also equipped educational facilities including observatories at UCLA, Westmont College, Pasadena City College, Bevard Community College, and many others. A Carroll telescope boasting a particularly distinguished educational history was a small astrograph built in 1953 for Professor George Moyen of Hollywood and subsequently used for the long-running Summer Science Program in Ojai, California. Later solar instruments built by Carson Instruments were closely derivative of Carroll designs.
2:30 4. Los Angeles and Its Influence on Professional and Popular Astronomy—A Hollywood Love Story
Lew Chilton, Los Angeles Astronomical Society.
The purpose of this presentation is to show through visualizations how the Los Angeles, California milieu of the early 20th century benefited the advancement of astronomy and captured the public consciousness through popular press accounts of these advancements and of the scientists who made them. The thesis of this presentation purports that a symbiosis developed between astronomers of Los Angeles-area scientific and educational institutions and a local community of interested laypersons, and was the catalyst that sparked future generations to enter the fields of astronomy, the allied sciences, education and technology. This presentation attempts to highlight the importance of continued public outreach by the professional astronomical community, for the ultimate benefit to itself, in Los Angeles and beyond.
2:50 5. Public Performance
E.C. Krupp, Griffith Observatory.
America's first planetaria all opened in the 1930s, and each was the distinctive product of local circumstances. In Los Angeles, the populist sensibilities of Griffith J. Griffith prompted him to value the transformative power of a personal encounter with a telescope, and he quickly embraced the idea of a public observatory with free access to all. Griffith Observatory and its planetarium emerged from that intent. Authenticity, intelligibility, and theatricality were fundamental principles in Griffith’s thinking, and they were transformed into solid and enduring scientific and astronomical values by those who actually guided the Observatory’s design, construction, and programming. That said, the public profile of Griffith Observatory was most defined by its inspired hilltop location, its distinctive, commanding architecture, and its felicitous proximity to Hollywood. The Observatory is theatric in placement and in appearance, and before the Observatory even opened, it was used as a motion picture set. That continuing vocation turned Griffith Observatory into a Hollywood star. Because entertainment industry objectives and resources were part of the Los Angeles landscape, they influenced Observatory programming throughout the Observatory’s history. Public astronomy in Los Angeles has largely been framed by the Observatory’s fundamental nature. It has exhibits, but it is not a museum. It has a planetarium, but it is essentially an observatory. As a public observatory, it is filled with instruments that transform visitors into observers. This role emphasized the importance of personal experience and established the perception of Griffith Observatory as a place for public gathering and shared contact with the cosmos. The Observatory’s close and continuous link with amateur astronomers made amateurs influential partners in the public enterprise. In full accord with Griffith J. Griffith’s original intent, Griffith Observatory has all been about putting people eyeball to the universe with authenticity, showmanship, and style.
3:10 6. Commentary
David DeVorkin, Smithsonian Institution.
Commentary based upon the papers in this session will focus on historical issues relevant to promoting science literacy.
3:30 End of session.
HAD II Special: Preservation of Astronomical Heritage and Archival Data
Session #91: Sunday, 6 Jan 2013, 4:00–6:00 p.m. Room 103B
Session Chair: Wayne H. Osborn, Central Michigan University.
4:00 Description: This session will deal with preserving astronomy’s rich cultural heritage, including its largely untapped archival collections of scientific data, sites of historical importance and the many historical papers and instruments that have yet to be scholarly discussed. In January 2007, in response to concerns that parts of the heritage were in serious danger of being lost, the AAS created the Working Group on the Preservation of Astronomical Heritage (WGPAH) charged with “developing and disseminating procedures, criteria and priorities for identifying, designating, and preserving astronomical structures, instruments, and records so that they will continue to be available for astronomical and historical research, for the teaching of astronomy, and for outreach to the general public.” In 2008 the IAU and UNESCO’s World Heritage Committee approved the Astronomy and World Heritage Initiative (AWHI) which aims to “identify, safeguard and promote cultural properties connected with astronomy.” Now five years on with WGPAH and AWHI, it is an appropriate time to see what has been accomplished.
Wayne H. Osborn and Jim Lattis, Session Organizers
4:05 1. UNESCO’s Astronomy and World Heritage Initiative: Progress to Date and Future Priorities?
Clive Ruggles, University of Leicester.
UNESCO's thematic initiative on Astronomy and World Heritage was created in 2005 "to establish a link between science and culture on the basis of research aimed at acknowledging the cultural and scientific values of properties connected with astronomy." Since 2008, when a formal Memorandum of Understanding (MoU) was signed between the IAU and UNESCO to work together to advance the Initiative, the IAU, through its Working Group on Astronomy and World Heritage, has been working to help identify, safeguard and promote the world’s most valuable cultural properties connected with astronomy. The Working Group's first major deliverable was the Thematic Study on the Heritage Sites of Astronomy and Archaeoastronomy, which was prepared in collaboration with ICOMOS, the Advisory Body to UNESCO that assesses World Heritage List applications relating to cultural heritage. Published in 2010, this has been endorsed by the World Heritage Centre as a basis for developing specific guidelines for UNESCO member states on the inscription of astronomical properties. The IAU's General Assembly in Beijing saw the launch of perhaps the most significant deliverable from the Initiative to date, the Portal to the Heritage of Astronomy (www.astronomicalheritage.net) which is a dynamic, publicly accessible database, discussion forum, and document-repository on astronomical heritage sites throughout the world, whether or not they are on UNESCO's World Heritage List. In recent months the Working Group has completed a set of nine "Extended Case Studies", which raise a wide range of general issues, varying from the integrity of astronomical sightlines at ancient sites to the preservation of dark skies at modern observatories. Given the progress that has been made to date, how would we wish to see the Initiative develop in the future and what should be the Working Group's priorities in the coming months and years? Among the suggestions I shall be discussing is that the WG should find ways to work more directly with national State Parties to encourage and help them prepare viable nominations for astronomical heritage sites on the World Heritage List.
4:45 2. Issues and Challenges in the Protection of Different Categories of Astronomical Heritage: A Report from Beijing 2012
Sara Schechner, Harvard University.
On the occasion of the IAU's General Assembly in Beijing in 2012, the Working Groups for Astronomy and World Heritage (WG-AWH) and Historical Instruments (WG-HI) of Commission 41 (History of Astronomy) — led by Clive Ruggles and Sara Schechner — held a joint science meeting concerning shared issues in the "Conservation and Protection of Different Categories of Astronomical Heritage." Since 2008, the WG-AWH had been working with UNESCO and its advisory bodies to identify and safeguard significant astronomical sites and assist in their eventual nomination for inclusion on the World Heritage List. That initiative was restricted to fixed sites and monuments. Moveable, tangible objects, such as scientific instruments, could not be included even though their significance was often interconnected with that of immovable sites. To address this concern, the 2012 joint science meeting convened international experts in the history, scientific, and cultural value of astronomical buildings, instruments, photographic plates, archives, and meteorites in order to discuss ways to develop and coordinate integrated approaches to the documentation and protection of these valuable things. A wide range of materials was discussed. It was evident that the historical, scientific, and cultural value assigned to any particular item might differ from one community to the next, and that the question of whom or what ultimately will determine how any heritage item is treated is complex, political, and negotiated. An important point of agreement was the idea of developing a "science heritage" (rather than "architectural heritage") approach in which the value is enhanced (rather than diminished) by changes to a facility that could lead to further scientific discoveries. It was hoped that such an approach would make observatory directors and others more comfortable with outside recognition of the heritage value of their working institutions.
5:10 3. Preserving a Piece of the True Cross
David H. DeVorkin, Smithsonian Institution.
I will discuss shared concerns of Curators and Collections Management Specialists at the National Air and Space Museum over the proper methods for identifying, documenting and preserving astronomical instrumentation in the Museum’s purview as well as in the realm of modern astronomical research. Questions of "what" and "how" will be raised and discussed, including the issue of preserving the historical character of instrumentation deemed still useful to astronomy. As part of this discussion, we will also consider: "why" make the effort to preserve? What is the value of a personal physical encounter with the "real thing?"
5:35 3. AAS Working Group on the Preservation of Astronomical Heritage (WGPAH): The Preservation of Astronomical Plates and Other Efforts
Wayne Osborn, WGPAH and Yerkes Observatory.
The WGPAH was created in 2007 in response to concerns that parts of astronomy’s rich heritage were in serious danger of being lost. Three classes of heritage were listed as of concern: (1) historically significant astronomical sites, (2) historically significant instruments, and (3) archives of historical documents and observations. During its six years the WG’s efforts have been directed mainly toward the third area, and in particular toward the preservation of astronomical plates. This talk first provides an overview of the WGPAH—charge, structure and membership. It then describes the results from its two major initiatives—the census of North American astronomical plates carried out in 2008 and the Workshop on Developing a Plan for preserving Astronomy’s Archival Records held in 2012. It concludes with the WG’s future challenges.
6:00 End of session.
HAD III Special: Fifty Years of Celestial X-ray Astronomy [Joint with HEAD]
Session #113: Monday, 7 Jan 2013, 10:00–11:30 a.m. Room 201B
Session Chairs: Hale Bradt, Massachusetts Institute of Technology and Richard Rothschild, University of California, San Diego.
Description: In the 50 years since the 1962 discovery of the first extrasolar x-ray source, the field of x-ray astronomy has grown from a few unidentified sources to a full-fledged branch of celestial astronomy. This session brings together 17 researchers from the early decades who will share with each other and the audience highlights of their experiences in an informal setting. The session will consist of three panels, and will be videotaped for the historical record. Each panelist will make a brief statement after which the panelists will engage in free discussion.
Hale Bradt and Richard Rothschild, Session Organizers
10:00 Panel 1: (Moderator: Richard Rothschild)
1. Two Amazing Rocket Launches That Began My Career
Richard E. Rothschild, University of California, San Diego.
I began my X-ray astronomy career by being given the responsibility for the Goddard rocket program by Frank MacDonald in the early 70’s. I am forever grateful to him and Elihu Boldt for the opportunity. The rocket’s observing program was three compact binary X-ray sources that could not have been more different: Cyg X-1, Cyg X-3, and Her X-1. A sounding rocket launch is nothing like a satellite launch with its large booster, Cape Canaveral experience, and lots of procedures and no touching of the hardware. First of all, one can walk up to the sounding rocket tower (at least you used to be able to) and go up in it to fix or adjust something with the yet-to-be-fueled rocket, booster, and payload just sitting there. At launch, you can see it up close (~100 m) and personal, and it is spectacular. There is an explosion (the Nike booster igniting), a bright flash of light, and it is gone in a second or two. And back in the block house, I watched Her X-1 pulse in real time, after Chuck Glasser calmed me down and explained that the detectors were not arcing but it was Her X-1. The Cyg X-1 observations resulted in the discovery of millisecond temporal structure in the flux from a cosmic source —13 1-ms bursts over a total of two minutes of observing in the 2 flights. Cyg X-3 was seen in a high state in the first flight and in a lower harder state in the second, where we detected the iron line for the first time in a Galactic source. The Her X-1 observation clearly showed the high energy roll-over of the spectrum for the first time. The light curves of the first flight found their way into many presentations, including Ricardo Giacconi’s Nobel lecture. The Goddard rocket program was an amazing beginning to my career.
2. Origins of the Rossi X-ray Timing Explorer Mission
Frederick Lamb, University of Illinois at Urbana-Champaign.
In the mid 1970s, X-ray astronomy missions such as Uhuru, SAS-3, HEAO-1, and others achieved dramatic scientific breakthroughs, such as the discovery of X-ray pulsars, thermonuclear X-ray bursts, and other rapid variations in X-ray emission from neutron stars and black hole candidates. However, by the late 1970s there were serious concerns that without a follow-on mission, these breakthroughs would not be followed up for many years. In 1978, I became convinced that further progress required a unified, community-wide effort, and I decided to organize such an effort. I offer here some personal recollections of my early involvement in this endeavor, which continued until the launch of the Rossi X-ray Timing Explorer (RXTE) in late 1995.
A key initial element of this effort was the April 1979 Washington Workshop that I organized in collaboration with David Pines. This workshop and its proceedings, the highly influential “Orange Book” titled Compact Galactic X-ray Sources and published in 1979, were carefully designed to achieve three goals: (1) to identify the key scientific questions, (2) to develop agreement within the U.S. astrophysics community on how these questions could best be addressed observationally, and (3) to build community-wide support for such a mission. The Washington Workshop and the “Orange Book” achieved all three of these goals. The participants unanimously endorsed the Workshop’s conclusions that further study of neutron stars and black holes was of the utmost scientific importance and that an Explorer-class X-ray timing mission could address the key outstanding scientific questions. Furthermore, the participants unanimously recommended that NASA initiate such a mission as soon as possible. Following the Washington Workshop and publication of the Orange Book, I energetically advocated creation of an X-ray timing mission in many venues, arguing the case to National Research Council and NASA advisory panels, the 1980 Astronomy Decadel Survey, the NASA Administrator and his deputies, and others, as well as in numerous talks at universities and scientific institutes. These efforts, and those of many others, helped make possible the creation of the enormously successful RXTE mission.
3. The Origin of the UCSD X-ray Astronomy Program—A Personal Perspective
Laurence E. Peterson, University of California, San Diego.
I was a graduate student in the late 1950's at the University of Minnesota in the Cosmic Ray Group under Prof. John R. Winckler. He had a project monitoring Cosmic ray time variations from an extensive series of balloon flights using simple detectors during the International Geophysical Year 1957-58. During the 20 March 1958 flight, a short 18 sec. burst of high energy radiation was observed simultaneously with a class II Solar flare. From the ratio of the Geiger counter rate to the energy loss in the ionization chamber, it was determined this radiation was likely hard X-rays or low-energy gamma rays and not energetic particles. Further analysis using information from other concurrent observations indicated the X-rays were likely due to Bremsstrahlung from energetic electrons accelerated in the solar flare magnetic field; these same electrons produced radio emissions. This first detection of extra-terrestrial X- or gamma rays showed the importance of non-thermal processes in Astrophysical phenomena. Winckler and I were interested by the possibility of non-solar hard X-rays. While completing my thesis on a Cosmic ray topic, I initiated a balloon program to develop more sensitive collimated low-background scintillation counters. This led to a proposal to the newly formed NASA to place an exploratory instrument on the 1st Orbiting Solar Observatory launched 7 March 1962. In August that year, I assumed a tenure-track position at UCSD; the data analysis of OSO-1 and the balloon program were transferred to UCSD to initiate the X-ray Astronomy program. The discovery of Cosmic X-ray sources in the 1-10 Kev range on a rocket flight in June 1962 by Giacconi and colleagues gave impetus to the UCSD activities. It seemed evident cosmic X-ray sources could be detected above 20 Kev using high-flying balloons. Early results included measurements of the 50 million K gas in SCO X-1, and the X-ray continuum from the Crab Nebula characterized by a power-law dN/dE ~ E-2.2. The instrument developments resulted in ever more sophisticated and sensitive counter systems. Follow-on instruments were flown on OSO-III and OSO-VII by the early 70's, the HEAO-1 in 1976, and the RXTE in 1995. These provided many new results on Cosmic X-rays.
4. X-ray Astronomy at Lawrence Livermore Laboratory 1965–1975
Frederick D. Seward, Harvard-Smithsonian Center for Astrophysics.
In 1965 a group of nuclear physicists at the Livermore Laboratory started to make observations of the X-ray sky. They found themselves in a unique situation - easy access to sounding rocket flights and generous support for instrument buiding and data analysis. The program continued for ten years. With rocket-borne detectors we showed that Sco X-1 was a thermal source and measured its approximate size and density. New sources were discovered in the southern sky including a bright transient and two luminous sources in the Large Magelanic Cloud. Detectors were developed for sub keV X-rays and three old supernova remnants were found to be the brightest sources in this energy band. These astronomy observations provided inspiration and challenge to the rocket development program and, in addition to these discoveries, a resource useful for the nation’s interests was developed.
5. The Diffuse Soft X-ray Background: Trials and Tribulations
Melville Ulmer, Northwestern University.
I joined the University of Wisconsin-Madison sounding rocket group at its inception. It was an exciting time, as nobody knew what the X-ray sky looked like. Our group focused on the soft X-ray background, and built proportional counters with super thin (2 micron thick) windows. As the inter gas pressure of the counters was about 1 atmosphere, it was no mean feat to get payload to launch without the window bursting. On top of that we built all our own software from space solutions to unfolding the spectral data. For we did it then as now: Our computer code modeled the detector response and then folded various spectral shapes through the response and compared the results with the raw data. As far as interpretation goes, here are examples of how one can get things wrong: The Berkeley group published a paper of the soft X-ray background that disagreed with ours. Why? It turned out they had **assumed** the galactic plane was completely opaque to soft X-ray and hence corrected for detector background that way. It turns out that the ISM emits in soft X-rays! Another example was the faux pas of the Calgary group. They didn't properly shield their detector from the sounding rocket telemetry. Thus they got an enormous signal, which to our amusement some (ambulance chaser) theoreticians tried to explain! So back then as now, mistakes were made, but at least we all knew how our X-ray systems worked from soup (the detectors) to nuts (the data analysis code) where as today “anybody” with a good idea but only a vague inkling of how detectors, mirrors and software work, can be an X-ray astronomer. On the one hand, this has made the field accessible to all, and on the other, errors in interpretation can be made as the X-ray telescope user can fall prey to running black box software. Furthermore with so much funding going into supporting observers, there is little left to make the necessary technology advances or keep the core expertise in place to even to stay even with today's observatories. We will need a newly launched facility (or two) or the field will eventually die.
6. From EXOSAT to the High Energy Astrophysics Science Archive (HEASARC): X-ray Astronomy Comes of Age
Nicholas White, NASA’s Goddard Space Flight Center.
In May 1983 the European Space Agency launched EXOSAT, its first X-ray astronomy observatory. Even though it lasted only 3 short years, this mission brought not only new capabilities that resulted in unexpected discoveries, but also a pioneering approach to operations and archiving that changed X-ray astronomy from observations led by small instrument teams, to an observatory approach open to the entire community through a guest observer program. The community use of the observatory was supported by a small dedicated team of scientists, the precursor to the data center activities created to support e.g. Chandra and XMM-Newton. The new science capabilities of EXOSAT included a 90 hr highly eccentric high earth orbit that allow unprecedented continuous coverage of sources as well as direct communication with the satellite that allowed real time decisions to respond to unexpected events through targets of opportunity. The advantages of this orbit demonstrated by EXOSAT resulted in Chandra and XMM-Newton selecting similar orbits. The three instruments on board the EXOSAT observatory were complementary, designed to give complete coverage over a wide energy band pass of 0.05-50 keV. An onboard processor could be programed to give multiple data modes that could be optimized in response to science discoveries. These new capabilities resulted in many new discoveries including the first comprehensive study of AGN variability, new orbital periods in X-ray binaries and cataclysmic variables, new black holes, quasi-periodic oscillations from neutron stars and black holes and broad band X-ray spectroscopy. The EXOSAT team generated a well-organized database accessible worldwide over the nascent internet, allowing remote selection of data products, making samples and undertaking surveys from the data. The HEASARC was established by NASA at Goddard Space Flight Center in 1990 as the repository of NASA X-ray and Gamma-ray data. The proven EXOSAT database system became the core of the HEASARC infrastructure. The HEASARC pioneered many concepts now taken for granted including standardized formats using FITS files, restoring data from earlier missions, multi-mission analysis tools and a searchable archive over the world wide web.
10:30 Panel 2: (Moderator: Hale Bradt)
7. The MIT Program, Competition, and Ethics
Hale Bradt, MIT.
The MIT program in x-ray astronomy was, and still is, diverse and productive. Bruno Rossi and later George Clark, as the nominal leaders of the “x-ray astronomy group” created a “hands-off” culture wherein individual researchers could develop their own independent programs. Walter Lewin, Claude Canizares, and I as well as those in the next academic generations, e.g., Saul Rappaport and George Ricker, were able to thrive in this environment. MIT researchers were principal investigators or providers of x-ray instruments on sounding rockets and balloons in the 1960s and then in later years on nine satellite missions, OSO-7, SAS-3, HEAO-1, Einstein, ASCA, RXTE, Chandra, HETE-2, and Suzaku. Such a diverse program involved collaborations with other institutions and of course striving for primacy in discovery and competition for NASA resources. Looking back, I see a high degree of ethical behavior among the observational x-ray community during those years. In competition, we remembered that we might well be collaborating the following year and behaved accordingly. Many of us in the x-ray community had been friends since graduate school days and did not want to lose those relationships. Am I viewing the past through rose colored glasses? I think not. A vignette on this topic: In 1967, I was debating vigorously with Herb Gursky of AS&E about which institution, MIT or AS&E, should be the lead on the fourth paper (Oda et al. 1967, ApJ 148, L5) based on data from the 1966 AS&E rocket flight which had led to Allan Sandage’s (and Japanese) identification of Sco X-1 (Sandage, et al. 1966, ApJ. 146, 316). I and my Italian colleague, Gianfranco Spada, and our Japanese colleague, Minoru Oda, both then visiting MIT, had actively supported that flight. After one rather heated discussion with Herb about this,—I was the heated one; he always remained calm—he left my office saying: “Hale, however this comes out, let's remain friends.” I treasured that comment and still do; it remained a guiding light in all my future collaborations and competitions. How the dispute was resolved was much less important. In fact, everyone gave up a bit, and it ended amicably. We remained friends.
8. From Uhuru at CfA to SAS-3 at MIT: Looking for X-Ray Binaries in all the Right Places
Lynn R. Cominsky, Sonoma State University.
My career in X-ray astronomy started almost accidentally, when in 1975 I was hired fresh out of college as a “data aide” for the Uhuru satellite, in Riccardo Giacconi’s group at the Harvard-Smithsonian Center for Astrophysics. Working first for Mel Ulmer, and later for Bill Forman and Christine Jones, I learned the fundamentals of data analysis, and helped produce the Fourth Uhuru catalog of X-ray sources (Forman et al. 1978), as well as studying transient X-ray sources (Cominsky et al. 1978). Christine was the first woman scientist I had ever met, and with her encouragement, I applied to graduate school to continue on in X-ray astronomy. Lured down the street to MIT by the chance to work on SAS-3, I eagerly learned how to operate the satellite from a control room in the Center for Space Research. The SAS-3 group was led by Prof. George Clark, and it was my good luck that he was around during the holiday break in January 1978 when everyone else in the group was at an AAS meeting in Austin. A source I recognized from my Uhuru work, 4U0115+63, had reappeared, and I knew that it was likely to be a pulsar. With the help of George and Project Scientist Bill Mayer, I managed to send the commands to stop SAS-3 and point at the source. The 3.6 second pulsations were so strong that they could be seen in the raw data! This discovery made the New York Times, as 4U0115+63 was the first transient x-ray source shown to be in a binary system (Cominsky et al. 1978, Rappaport et al. 1978). Another personal SAS-3 highlight included working on Prof. Walter Lewin's "World-wide Burst Watch" — coordinated multi-wavelength observations of x-ray burst sources which led to the discoveries of slightly delayed but coincident optical bursts (Grindlay et al. 1978, McClintock et al. 1979). Although live operations of SAS-3 ended when it re-entered on April 9, 1979, many years of additional data analysis remained. And later, as a continuation of work I began in my Ph.D. Thesis on X-ray burst sources, I used SAS-3 data together with data from HEAO A-1 to discover the first true eclipses from an x-ray burster (MXB1659-29, Cominsky and Wood 1984), providing definitive evidence of the binary nature of a second class of x-ray sources.
9. Interplay Between Theory and Observation
Peter Serlemitsos, NASA’s Goddard Space Flight Center.
The Goddard X-ray group made its appearance in 1964 as a one person (Elihu Boldt) appendage to the well established cosmic ray group, then headed by Frank MacDonald. This discipline proximity was crucial because it meant superb technical support from the start, which allowed the fledging group to quickly advance toward directions of choice. When I became the 2nd member of the group in 1966, the new discipline still relied on bulky gas counters, stacked to make up a usable detection area. Slim opportunities existed for timing or spectral inferences. Elihu’s strong interest in pursuing the reported diffuse cosmic radiation had to be set aside, as improving this situation appeared to be years away. Cosmic ray researchers had long used charged particle timing techniques for cleaning up their data, but those appeared irrelevant for our purposes because of the large, background generating, mass of the gas containment vessels and the slow drift in the counter gas of the charge from photon interaction sites to the counter anode. We had to deal with these realities in whatever choices we made for our future instruments. The multi-wire gas proportional counter emerged from our still small group in the late1960s, demonstrating on several rocket and balloon flights a greatly reduced detector background, improved event timing and adequate resolution for addressing key spectral features. Three of these detectors, flown in 1975 on NASA’s 8th Orbiting Solar Observatory, were successfully used for some 3 years to conduct non dispersive, 1-10 keV spectroscopy on many galactic and extragalactic sources, including several clusters of galaxies. In 1977 we flew a set of larger detectors on the first of NASA’s High Energy Astrophysical Observatories (HEAO). These were specifically designed for the study of the X-ray background. Finally, the largest instruments of this family were flown in 1995 by our group on NASA’s Rossi X-ray Timing Explorer, RXTE, which observed, over a remarkable 16 year mission, msec pulsars, transient sources, galactic and extragalactic black holes, among others.
10. Interplay Between Theory and Observation
Jean Hebb Swank, NASA’s Goddard Space Flight Center.
>In the early 1970’s, after the rocket flights had identified some sources, Uhuru was surveying the sky, and neutron stars, black holes, supernova remnants, clusters of galaxies had been tentatively identified as responsible. Coming from a theoretical particle physics background, I was especially interested in the astrophysical manifestations of fundamental physics in neutron stars and black holes, and history shows the exciting interplay between theory and observation. OSO-8 provided my first example of an observation that made a clear simple identification; the cooling black body spectrum with constant radius strongly pointed to a neutron star as the source. The instrument had enough area, energy resolution and time resolution to see it. Unbeknownst to me, thermonuclear flashes of accreting material had been predicted and they had been proposed as the explanation for bursts. At the next level of detail, to accurately determine mass, to account for emissivity (the color correction) and general relativity, and use the observations to determine mass and radius, and the nuclear fuel, many other parameters play a role. RXTE was designed to answer many of the questions developed as a consequence of earlier missions. One of them was the question of whether the neutron stars in the bursts were spun up pulsars and whether the low frequency quasi-periodic pulsations (QPO) seen with EXOSAT and Ginga were interactions of the accretion disk and a pulsar. RXTE's first observations of low mass x-ray binaries showed the kilohertz quasi-periodic oscillations and the burst oscillations. The PCA had the area and the time resolution to see them. I should have known that kilohertz QPO had also been predicted. Again, while some aspects are simple, at the next level, for both neutron stars and black holes, many other parameters and questions of interpretation must be considered. These especially affect the ability to use the sources identified as black holes to understand their influence on space-time. It was to look at these sources with a different tool that the Gravity and Extreme Magnetism SMEX GEMS was proposed. Its termination because of cost predictions is an example of the severe practical difficulties of astrophysics.
11. My 35 Years in X-ray Astronomy (Not)
C. Megan Urry, Yale University.
My contact with X-ray astronomy started with HEAO-1, just before launch, when I was a summer student at the Harvard/Smithsonian Center for Astrophysics. Another summer position followed at NASA’s Goddard Space Flight Center, where I later did my PhD thesis on HEAO1 and HEAO2 (and IUE) data. Next I was a postdoc at MIT working with Einstein and Ginga observations, and I then continued observing blazars and other AGN with ASCA, Exosat, RXTE, Chandra, XMM, Swift, Suzaku, and Fermi. I have also witnessed or participated in many proposals for future X-ray missions. Fortunately for the audience, I will not recall all these times ... So many photons, so little time! But this long history does mean I met most of the great figures in X-ray astronomy when they were young and I probably have embarrassing stories to tell about many of them. For my 2-minute vignette in a panel discussion, I will entertain you with one of the more interesting (and pertinent) memories.
Acknowledgement: Thank you to all my high-energy astrophysics colleagues, who taught me a great deal, and to NASA for the hit parade of high-energy missions.
12. Sliding Up and Down the Spectrum: Rocket, Balloon, and Satellite X-ray Detectors Over the Past Fifty Years
George Ricker, MIT.
Beginning in 1965, I had the wonderful opportunity to work with the several research groups in high-energy astronomy founded by Bruno Rossi at MIT. As an undergraduate in George Clark’'s lab, I first learned about the challenges of detecting X-ray polarization with gas-filled counters. As a graduate student with Walter Lewin, the subtleties of scintillators and surveying the Galactic Center from balloons became my focus. In the mid-70s, I drank from the fire hose of SAS-3, along with my many postdoc friends and MIT colleagues. In the 1980s, the MIT CCD Laboratory, which I helped found, was able to develop the first photon-counting, imaging X-ray CCD spectrometers to be flown in space on the ASCA mission. In the 1990’'s, our group was privileged to contribute CCD X-ray cameras to both the Astro-E and Chandra missions. In 2000, we assembled and flew HETE-2, the first satellite entirely dedicated to the rapid localization and study of gamma-ray bursts. During this 4+ decades period, the vibrant excitement of experimental X-ray astronomy was always there. Hopefully, the excitement will return for a newer generation in the coming decade, as new technology detectors and telescopes emerge from the laboratory, and X-ray satellite flight opportunities once again are accorded high priority.
11:00 Panel 3: (Moderator: Richard Rothschild)
13. The Discovery of X-ray Emission from Active Galactic Nuclei
Martin Elvis, Harvard-Smithsonian Center for Astrophysics.
Back in 1974 the UHURU catalog (3U) had been published with many UHGLS — unidentified high galactic latitude sources. Identifications were hampered by the square degree sized error boxes (positional uncertainties). Could these explain the cosmic X-ray background? Could UHGLS be “X-ray galaxies”? Only three active galaxies (AGNs) had been found as X-ray sources: 3C273, Cen A and NGC 4151, while others had upper limits. What was the difference between X-ray and non-X-ray AGNs? It turned out that the slightly better positioning capability and slightly deeper sensitivity of the Ariel V Sky Survey Instrument (SSI), launched in October 1974, were just enough to show that the UHGLS were Seyfert galaxies. And I was lucky enough that I’d joined the Leicester X-ray group and had taken on the UHGLS for my PhD thesis, with Ken Pounds as my supervisor. With the SSI we made a catalog of high latitude sources, the “2A” catalog, including about a dozen known Seyfert galaxies (lowish luminosity nearby AGNs) and, with Mike Penston and Martin Ward, we went on to identify many of them with both newly discovered normal broad emission line AGNs and a few new “narrow emission line galaxies”, or NELGs, as we called them. We are now convinced that it is summation of many obscured NELGs that produce the flat spectrum of the X-ray background, and we are still searching for them in Chandra deep surveys and at higher energies with NuSTAR. There was an obvious connection between the X-ray obscuration and the optical reddening, which must lie outside the region emitting the broad optical spectral lines. Andy Lawrence and I, following a clue from Bill Keel, put this together into what we now call the Unified Scheme for AGN structure. This idea of a flattened torus obscuring the inner regions of the AGN was so dramatically confirmed a few years later—by Ski Antonucci and Joe Miller’s discovery of polarized broad emission lines in NGC1068—that the precursor papers became irrelevant. But Ariel V had provided the seeds for this advance too. Not bad for 100cm2 and 1/2 degree collimators.
14. The Chandra XRCF Calibration Experience—A Personal Recollection
Kathryn Flanagan, Space Telescope Science Institute.
My undergraduate thesis research involved calibrating an imaging proportion counter for the Focal Plane Crystal Spectrometer on the Einstein X-ray Observatory. The testing was done in a laboratory on the 5th floor of MIT's Center for Space Research, with one or two other people in the room. Years later, when I joined the Chandra project, I had the unique experience of participating in the calibration of the mirrors and detectors at the X-Ray Calibration Facility (XRCF) at the Marshall Space Flight Center in Huntsville Alabama. This was an eye-opening experience of an entirely different magnitude! A quarter-mile long vacuum tube extended from an X-ray source building to a two-story structure housing a gigantic vacuum test chamber. Teams representing every part of the Observatory worked 24 hours a day, seven days a week for nearly half a year. This experience represented an immense milestone—for the Observatory, perhaps for X-ray astronomy, and certainly for the people who worked so hard (and sacrificed so much) to achieve it.
15. So Many Rockets—The Road to High Resolution Imaging in X-rays
Stephen S. Murray, Johns Hopkins University & Harvard-Smithsonian Center for Astrophysics.
When I first begin to work on new imaging detectors for X-ray Astronomy I was at AS&E and I worked with Leon Van Speybroeck and Ed Kellogg on a sounding rocket project. We starting by using a microchannel plate image intensifier to detect X-ray photons and convert them to flashes of light that were recorded on 35 mm film frames. Simultaneously there was a 16 mm star camera taking frames so we could tell where the X-rays were coming from. I spent about 6 years working on this payload, eventually becoming the PI and evolving the detector from a film readout to an electronic readout (the crossed grid charge detector) that was the basis for the Einstein, ROSAT and Chandra High Resolution Imagers and Cameras. We had a series of about 6 or so rocket flights culminating in the 1978 flight that actually worked. We detected three photons from Sco X1, and background data from that flight allowed us to set the detector front bias voltage to minimize non-X-ray background for the Einstein HRI. Just about everything that could go wrong on those rockets did go wrong, from a switch not closing to a rocket misfire, to pointing 180 degrees off target. But we learned something each flight and kept coming back to try again. The worse thing for me was having to stay up all night at White Sands in a small darkroom where I could avoid the night crawlers and scorpions that frightened me to death. Not to mention the daredevil helicopter pilots who flew us to the recovery site hugging the ground at top speed all the way there! None-the-less, in the end we succeeded in our goals, and there is nothing so exciting as watching your payload being launched at night (even it did mean sneaking out from the bunker to do it!). Thanks to NASA and the US Navy’s White Sands USS Desert Ship (LLS-1; Land Locked Ship-1) for all the support.
16. The HEAO-1 Scanning Modulation Collimator
Daniel A. Schwartz, Harvard-Smithsonian Center for Astrophysics.
My niche on this panel seems to be the High Energy Astronomy Observatory-1 Scanning Modulation Collimator experiment. Our chair, Hale Bradt, and the late Herb Gursky each proposed a different version modulation collimator, which was condensed by NASA via “forced marriage,” to the SMC. I worked as Project Scientist under Herb, later inheriting the PI role. The MIT Project Scientist, the late Rodger Doxsey, and I were told “this is your experiment,” and “we are a seamless team regardless of institution.” Rodger and I were young enough to believe this, and we made it happen (and not always with the best results vis a vis higher internal management). I was never interested in astronomy, and allegedly am still not. Why do an astro-metrical job of measuring and reporting the coordinates of X-ray sources? In fact we participated widely in the identification of the sources with astronomical objects, and making each paper a discussion of the physics of the emission. An enjoyable way to learn some astronomy. The stated purpose of the Gursky/Bradt experiment was to enable optical identifications so that more detailed study could be done. I remember meeting with John Whelan to discuss his collaboration in making the optical identifications. He said he only wanted to study sources after they were identified. For many milliseconds I became very angry — "who is going to to the work to MAKE those identifications," but luckily before speaking I realized how satisfying it was that astronomers indeed wanted to study X-ray sources in other wavebands. The second biggest excitement in the HEAO-1 program was the “glitches” that appeared in the gyro data during final functional testing. This took some high-powered politics by all the PI’s to convince MSFC to delay for 4 months, replacing the “funny” unit with one from HEAO-2 (Einstein) and later refurbishing that unit. Third biggest excitement was when a computer failed and final checkout during countdown at the Cape was done by looking at lights on ground support equipment. Biggest excitement was cancellation of the entire HEAO program late on a Friday afternoon in January 1971. It took a year of study and re-configuration as a series of 3, instead of 4, satellites to reinstate.
17. From a Sounding Rocket per Year to an Observatory per Lifetime
Martin Weisskopf, NASA’s Marshall Space Flight Center.
When I began my career as an X-ray astronomer/astrophysicist we launched new experiments at a cadence of approximately one per year. The majority of each these projects involved a newly developed instrument, revolutionary for its time. Then, innovation in instrument development could proceed in parallel with friendly competition amongst a number of groups. Thus, I was privileged to help develop and fly X-ray concentrators and telescopes, crystal spectrometers, and two types of X-ray polarimeters. I have also been privileged to play a central role in design, development, calibration and operation of the Chandra X-Ray Observatory. I will contrast these phases of my career both from a historical perspective and for the lessons I would pass on for the future.
11:30 End of session.
Additional abstracts for Special Session III (submitters will not be present):
X-ray Fe-lines from Relativistic Accretion Disks Around Neutron Stars and Black Holes
Luigi Stella, Osservatorio Astronomico di Roma.
The Gas Scintillation Proportional Counter (GSPC) on board the European X-ray Satellite EXOSAT (1983-1986) provided detections of Fe K-alpha emission features around 6-7 keV in the X-ray spectra of accreting neutron star and black hole candidates in X-ray binaries. Surprisingly the width of these lines was found to be broader than the GSPC resolution (~10% at 6 keV): it could not be explained by thermal broadening, nor blending of (unresolved) lines from different ionization stages of Fe; very large Doppler shifts and, perhaps, thermal Comptonisation provided more promising interpretations. In 1989 Nick White and I developed the first general relativistic model for the Fe-line profile that is produced by matter orbiting in an accretion disk. By fitting the GSPC Fe-line of the black hole candidate Cyg X-1 with our model we inferred an emitting line region extending to a few tens Schwarzschild radii from the black hole, where matter orbits at ~0.1-0.2 the speed of light and effects such as relativistic Doppler shifts and boosting, as well as gravitational and transverse redshifts are conspicuous. We joined forces with Andy Fabian and Martin Rees, who were working on the same interpretation, and published the results in a MNRAS paper. The relativistic disk interpretation of the broad Fe-lines gave rise to much interest on the possibility of measuring black hole mass and spin and probing the innermost regions of accretion flows and the very strong gravitational fields close to compact objects. Very broad and sometimes highly redshifted Fe-lines have been studied by now in tens of X-ray binaries and bright Active Galactic Nuclei with the CCD detectors of the Chandra and XMM/Newton X-ray telescopes; in some cases the line profile implies the presence of a fast spinning black hole. The potential of the Fe-line diagnostics remains to be largely exploited. Moreover some alternative interpretations are not yet ruled out. An X-ray instrument with a broad energy response, spectral resolution of ~200 eV and effective area in the 10 m2 range, such as the LAD of the proposed ESA M3 mission LOFT, will afford a quantum leap in this field of research.
Technological and Scientific Advances from Uhuru to Chandra
Christine Jones, Harvard-Smithsonian Center for Astrophysics.
The technological and scientific advances from Uhuru to Chandra have been revolutionary. While Uhuru observations provided major discoveries ranging from accreting neutron stars in binary systems to the detection of quasars and the hot intracluster medium in clusters of galaxies, Chandra’s high angular resolution has led to advances in all areas of astrophysics, from solar system objects to high redshift quasars. This contribution will highlight our advances in the study of galaxies and clusters, particularly the study of AGN feedback and major cluster mergers.>
HAD IV History Poster Papers
Session #151: Monday, 7 Jan 2013, 9:20 a.m.–6:30 p.m. Exhibit Hall A
1. Boller and Chivens: Preserving the History of the Preeminent Telescope Maker of its Era
Peter Abrahams, Historical Astronomy Division, AAS & D. Winans, Boller and Chivens.
The Boller and Chivens Company, of South Pasadena, was the leading precision manufacturer of astronomical equipment in the post-WWII era. Recently, veteran employees of the company have engaged in a major effort to document the products, employees, and engineering of B&C. The results can be seen at http://bollerandchivens.com/ . This poster will provide an overview of this ongoing project.
2. Working Group Proposed to Preserve Archival Records
Jennifer L. Bartlett, US Naval Observatory. & Participants in Workshop on Developing a Plan for Preserving Astronomy’s Archival Records
The AAS and AIP co-hosted a Workshop in April 2012 with NSF support (AST-1110231) that recommends establishing a Working Group on Time Domain Astronomy (WGTDA) to encourage and advise on preserving historical observations in a form meaningful for future scientific analysis. Participants specifically considered archival observations that could describe how astronomical objects change over time. Modern techniques and increased storage capacity enable extracting additional information from older media. Despite the photographic plate focus, other formats also concerned participants. To prioritize preservation efforts, participants recommended considering the information density, the amount of previously published data, their format and associated materials, their current condition, and their expected deterioration rate. Because the best digitization still produces an observation of an observation, the originals should be retained. For accessibility, participants recommended that observations and their metadata be available digitally and on-line. Standardized systems for classifying, organizing, and listing holdings should enable discovery of historical observations through the Virtual Astronomical Observatory. Participants recommended pilot projects that produce scientific results, demonstrate the dependence of some advances on heritage data, and open new avenues of exploration. Surveying a broad region of the sky with a long time-base and high cadence should reveal new phenomena and improve statistics for rare events. Adequate financial support is essential. While their capacity to produce new science is the primary motivation for preserving astronomical records, their potential for historical research and citizen science allows targeting cultural institutions and other private sources. A committee was elected to prepare the WGTDA proposal. The WGTDA executive committee should be composed of ~10 members representing modern surveys, heritage materials, data management, data standardization and integration, follow-up of time-domain discoveries, and virtual observatories. The Working Group on the Preservation of Astronomical Heritage Web page includes a full report.
HAD Business Meeting
Session #119: Monday, 7 Jan 2013, 12:45–1:45 p.m. Room 201B
Session Chair: Jarita Holbrook, University of California, Los Angeles.
HAD V History of Astronomy, including Osterbrock Book Prize Lecture
Session #130: Monday, 7 Jan 2013, 2:00–3:30 p.m. Room 103B
Session Chair: Jarita Holbrook, University of California, Los Angeles.
2:00 1. Almagest Declinations: Timocharis, Aristyllus, and Hipparcus
Peter C. Zimmer & John C. Brandt, University of New Mexico & P.B. Jones, University of Arizona.
Declinations in the Almagest provide an opportunity to determine the observational precision of the ancient observers and their epochs. The basic data are the original observations (O) and the declinations calculated (C) by precessing modern positions and including refraction. The plots of (O) – (C) can be analyzed using several different approaches. All of the original positions appear to be valid except Timocharis’s value for Arcturus. Consistent results for the precisions and epochs, respectively, are: Timocharis—8.1 arc min, near 296BC; Aristyllus--5.3 arc min, near 258BC; and Hipparcus--6.8 arc min, near 130BC. See the papers by Pannekoek (1955), Maeyama (1984), Rawlins (manuscript, c. 1983), and our earlier (Brandt, Zimmer, and Jones, 2011) report for the development of this subject. The precisions in the range 5-8 arc min are remarkable and the dates are compatible with historical evidence.
2:15 2. Blurring the Boundaries Among Astronomy, Physics, and Chemistry: The Moseley Centenary
Virginia L. Trimble, University of California, Irvine.
Scientists, like other human beings, are territorial animals, not just about our parking spaces and seats in the colloquium room, but also about our scientific territories, from the narrowest thesis topic ("Who's been working on my Nebula and left it covered with dust?") to the whole of physics, or chemistry, or astronomy. Many 19th century astronomers resented spectroscopes invading their observatories; chemists objected to Moseley's use of X-ray outgaming their retorts and test tubes in 1913; and chemists and physicists typically disbelieve astronomers suggesting new science on the basis of astronomical data (three other combinations are also possible). The talk will explore some of these transgressions, both a few spectacular successes and rather more awkward failures. Moseley's own contributions included sorting out the rare earths, putting paid to nebulium and coronium as elements between H and He, many years before improved understanding of atomic structure led to correct identifications of the ionization states and transitions actually responsible for the lines credited to them, and putting Prout's hypothesis on a firm foundation ready for the structure Cameron and B2FH would eventually erect there. Back in 1935, Gamow asked whether a new discipline should be called nuclear physics or nuclear chemistry (both now exist, within APS and ACS respectively), and 30+ years later, chemist L.S. Trimble was still complaining that the physicists had grabbed away the territory of atomic and nuclear composition, which should have been part of chemistry!
2:30 3. Mingantu, 18th-Century Mongol Astronomer and Radioheliograph Namesake
Jay M. Pasachoff, Williams College & Caltech.
The 18th-century Mongol astronomer Mingantu (1692-1765) has been honored with a city named after him and a nearby solar telescope array. During the IAU/Beijing, my wife and I went to the new Chinese solar radioheliograph, the Mingantu Observing Station, in Inner Mongolia, ~400 km northwest of Beijing, a project of the National Astronomical Observatories, Chinese Academy of Sciences. It currently contains 40 dishes each 4.5 m across, with a correlator from Beijing. Within a year, 60 2-m dishes will be added. We passed by the 12-century ruins of Xanadu (about 20 km north of Zhangbei) about halfway. The radioheliograph is in a plane about 1 km across, forming a three-armed spiral for interferometric solar mapping, something colleagues and I had carried out with the Jansky Very Large Array, taking advantage of the lunar occultation before annularity at the 20 May 2012 solar eclipse. In the central square of Mingantu city, a statue ~10-m high of the Mongol astronomer Mingantu appears. Its base bears a plaque ~1-m high of IAU Minor Planet Circular MPC 45750 announcing the naming in 2002 of asteroid 28242 Mingantu, discovered at a Chinese observatory in 1999. Mingantu carried out orbital calculations, mapping, mathematical work on infinite series, and other scientific research. He is honored by a modern museum behind the statue. The museum’s first 40% describes Mingantu and his work, and is followed by some artifacts of the region from thousands of years ago. The final, large room contains a two-meter-square scale model of the radioheliograph, flat-screen televisions running Solar Dynamics Observatory and other contemporary visualizations, orreries and other objects, and large transparencies of NASA and other astronomical imagery. See my post at http://www.skyandtelescope.com/community/skyblog/newsblog/Astro-Sightseeing_in_Inner_Mongolia-167712965.html. We thank Yihua Yan for arranging the visit and Wang Wei (both NAOC) for accompanying us. My solar research is supported by grant 1047726 from the Solar Research Program/Atmospheric and Geospace Sciences Division/NSF. I am also grateful for a NSF travel grant through AAS.
2:45 Presentation of 2nd Donald E. Osterbrock Book Prize
Jarita C. Holbrook, University of California, Los Angeles.
2:50 Osterbrock Prize Lecture: Astronomical Records in the Hieroglyphic Writings of the Precolumbian Maya
Harvey M. Bricker and Victoria R. Bricker, Tulane University and University of Florida.
The four screen-fold hieroglyphic books of the Precolumbian Maya that have survived into modern times, known collectively as the Maya codices, provide the most detailed information about the astronomical knowledge and practices that can be attributed to this New World civilization. Four explicitly dated documents in the Dresden Codex treat the cyclical movements of Venus and Mars and both solar and lunar eclipses during several centuries of the Maya Classic and Postclassic, primarily the 8th through the 14th centuries. In addition, these documents deal with the effects on peoples’ lives that were considered to result from these celestial phenomena. A heavily damaged document in the Paris Codex provides information about the Precolumbian Maya view of zodiacal constellations. The lecturers will explain what is in these astronomical records and discuss some of the techniques used to understand them.
3:30 End of session.
HAD VI History of Astronomy
Session #208: Tuesday, 8 Jan 2013, 10:00–11:30 a.m. Room 103B
Session Chair: Jay M. Pasachoff, Williams College.
10:00 1. Almagest Declinations: Ptolemy or “As found by us”
John C. Brandt & Peter C. Zimmer, University of New Mexico, & P.B. Jones, University of Arizona.
Consistent results and compatibility with historical evidence were reported by Zimmer, Brandt, and Jones for Almagest declinations determined by Timocharis, Aristyllus, and Hipparcus. Unfortunately, this situation does not apply to the Almagest declinations (Book VII, Chapter 3; Toomer 1998) for Ptolemy or “As found by us.” Our formal solution gives a precision of 11.9 arc min and an epoch near 115AD. The precision is significantly worse than for the earlier observers and the date conflicts with historical data. Inspection of the (O) – (C) plots vs. year reveals that the natural clustering of trajectories seen for the other observers is not seen for the Ptolemy declinations. In addition, the spread in dates of observations estimated from the times of (O) – (C) = 0 shows a much larger value for Ptolemy than for the others. Historically, the Almagest was published around 150AD or perhaps a little later. Ptolemy’s life span was likely from c.100AD to c.175AD. Thus, the 115AD date for his observations is much too early. Maeyama (1984) moved the epoch from 115AD to 137/138AD by dropping stars from the analysis. Rawlins (manuscript, c. 1983) has an extensive discussion, drops several stars, and finds a preferred epoch of 137AD. He regards the observer as unknown. We prefer not to drop stars from the analysis unless the evidence is overwhelming. Our solution is to take Ptolemy literally. In Toomer (1998; tables on pages 331 & 332), these declinations are “As found by us” and in Taliaferro (1952; in the text) are as “we find it.” The idea of multiple observers has been suggested before and our analysis certainly supports the declinations coming from multiple observers through the years.
10:15 2. On the Late Development and Possible Astronomical Origin of the Gyroscope
Kenneth Brecher, Boston University.
The invention of the gyroscope is usually attributed to the French physicist Jean-Bernard-Leon Foucault in the year 1852. He certainly created the word and also used his gyroscope to demonstrate the rotation of the Earth. However, the gyroscope was actually invented around 1812 by the German scientist Johann Bohnenberger who called his device simply the “machine”. Bohnenberger was a professor of astronomy and mathematics and published a book about astronomy in 1811. Several other scientists, including American physicist Walter R. Johnson (who called his apparatus the “rotascope”), independently invented the gyroscope. Each of these devices employed a central object (sphere or disc) that could spin on a shaft. This object was placed between three independent gimbals, two of which could move freely. Bohnenberger’s “machine” has much the same appearance as an armillary sphere. Those astronomical devices had been produced for at least the preceding three centuries and were widely dispersed and well known throughout Europe. They were used to display the apparent motion of celestial bodies. However, armillary spheres were used only as simulations of celestial appearances, not as actual demonstrations of physical phenomena. It is not known if the inertial properties of armillary spheres (and also of terrestrial and celestial globes) had been studied before about 1800. Nonetheless, as a matter of practice, gimbal systems similar to those found in gyroscopes were used on ships to level oil lamps at least as early as the sixteenth century AD. And the ideas behind armillary spheres date back at least a millennium before that. So why did the invention of the gyroscope in its modern form take such a long time when the individual underlying components had been around and utilized for some two millennia? Perhaps because the understanding of angular momentum, including its conservation, was not developed until the start of the 19th century and also because the technologies necessary to make practical gyroscopes were only developed later in the 19th century. This study was supported in part by NSF Grant # DUE-0715975 for Project LITE.
10:30 3. The Recurrent Nova T CrB Did Not Erupt In 1842
Bradley E. Schaefer, Louisiana State University.
The recurrent nova T CrB was one of the first well observed nova eruptions in 1866, and 80 years later it erupted again in 1946. Just after the 1866 eruption, Sir John Herschel reported to the Monthly Notices that he had seen the same star in his naked-eye charting of the sky on 1842 June 9, implying that there was a prior eruption 24 years earlier, with substantial implications for astrophysics. Unfortunately, the chart in the Monthly Notices was ambiguous and misleading, including whether the recorded position is or is not that of T CrB. So it has long been unclear whether T CrB did indeed have an eruption in 1842. To resolve this, I have made complete searches through the various archives with Herschel material, including the large collections at the Harry Ransom Center in Austin, the Royal Astronomical Society, the complete Herschel correspondence, and the Royal Society; plus three smaller archives as well as consulting with various Herschel experts. In one letter from 1866 to William Huggins, Herschel enclosed his own copy of his original observations, and with this all the ambiguities are resolved. It turns out that Herschel's indicated star was at the same position as a steady background star (BD+25 3020, V=7.06, G8V) and not that of T CrB, and Herschel regularly was seeing stars as faint as V=7.5 mag because he was using an opera glass. With this, there is no evidence for a T CrB eruption in 1842. Supported by the National Science Foundation.
10:45 4. Hamilton Jeffers and the Double Star Catalogues
Joseph S. Tenn, Sonoma State University.
Astronomers have long tracked double stars in efforts to find those that are gravitationally-bound binaries and then to determine their orbits. Court reporter and amateur astronomer Shelburne Wesley Burnham (1838-1921) published a massive double star catalogue containing more than 13,000 systems in 1906. The next keeper of the double stars was Lick Observatory astronomer Robert Grant Aitken (1864-1951), who produced a much larger catalogue in 1932. Aitken maintained and expanded Burnham’s records of observations on handwritten file cards, eventually turning them over to Lick Observatory astrometrist Hamilton Moore Jeffers (1893-1976). Jeffers further expanded the collection and put all the observations on punched cards. With the aid of Frances M. “Rete” Greeby (1921-2002), he made two catalogues: an Index Catalogue with basic data about each star, and a complete catalogue of observations, with one observation per punched card. He enlisted Willem van den Bos of Johannesburg to add southern stars, and they published the Index Catalogue of Visual Double Stars, 1961.0. As Jeffers approached retirement he became greatly concerned about the disposition of the catalogues. He wanted to be replaced by another “double star man,” but Lick Director Albert E. Whitford (1905-2002) had the new 120-inch reflector, the world’s second largest telescope, and he wanted to pursue modern astrophysics instead. Jeffers was vociferously opposed to turning over the card files to another institution, and especially against their coming under the control of Kaj Strand of the U.S. Naval Observatory. In the end the USNO got the files and has maintained the records ever since, first under Charles Worley (1935-1997), and, since 1997, under Brian Mason. Now called the Washington Double Star Catalog (WDS), it is completely online and currently contains more than 1,000,000 measures of more than 100,000 pairs.
11:00 5. Fifty Years of Quasars
Kenneth I. Kellermann, NRAO.
Although the extragalactic nature of quasars was discussed as early as 1960, it was dismissed largely because of preconceived ideas about what appeared to be an unrealistically high luminosity. Following the 1962 occultations of the strong radio source 3C 273 at Parkes, and the subsequent identification with an apparent stellar object, Maartin Schmidt recognized that the relatively simple hydrogen line Balmer series spectrum implied a redshift of 0.16 leading to the general acceptance of the quasars as being extragalactic origin and the most luminous objects in the Universe. Subsequent radio and optical measurements quickly led to the identification of other quasars with increasingly large redshifts. However, claims for a more local population continued for at least several decades confused perhaps by the recognition of the much larger class of radio quiet quasars and active galactic nuclei (AGN), and the uncertain connection with Seyfert galaxies and Zwicky’s compact galaxies. Curiously, 3C 273, which is one of the brightest extragalactic extragalactic sources in the sky, was first catalogued in 1959 and the mag 13 optical counterpart was known at least as early as 1887. Although, since 1960, much fainter optical counterparts were being routinely identified using accurate radio interferometer positions, 3C273 eluded identification until the series of lunar occultations by Cyril Hazard and others were used to determine the position and morphology of the radio source.
11:15 6. Hubble’s Law: Who Discovered What and When
Ian Steer, NASA/IPAC Extragalactic Database.
Controversy continues over who discovered the Universe’s expansion. Was it Hubble, Lemaître, or perhaps even Lundmark? However, extragalactic distance estimates published by Hubble and his contemporaries to prove expansion have been tabulated and made publicly available online by the NASA/IPAC Extragalactic Database of galaxy Distances, which I co-lead. In 1924, three years before Lemaître’s research and five years before Hubble’s, Lundmark’s distance estimates were consistent with a Hubble constant of H0 = 75 km/s/Mpc. This is within 1% of the best Hubble constant estimates today, but Lundmark’s research was not adopted. Hubble’s research of 1929 was. Although inaccurate by almost an order of magnitude, giving H0 = 500 km/s/Mpc, Hubble’s research relied on multiple methods including one still in use (brightest stars), calibrated by multiple galaxies with distances based on proven Cepheids variables. Lundmark established observational evidence that the Universe is expanding. Lemaître established theoretical evidence. Hubble established observational proof. This presentation will expand on earlier briefs given online, and in JRASC 105, 18 (2011), and Nature 490, 176 (2012) Correspondence.
11:30 End of session.