A major activity was the expedition to the total solar eclipse of
26 February 1998. Pasachoff organized a scientific expedition that
involved 8 students, including 4 seniors, two juniors, one junior
here on exchange, and one senior from another college who worked for
a colleague through our Keck Northeast Astronomy Consortium. All the
astrophysics majors participated.
Tim McConnochie `98, Bryce Babcock and Prof. Jay Pasachoff setting up the Celestron 14" telescope and fast CCD apparatus in preparation for the 2/26/98 total eclipse in Aruba. The eclipse expedition was to Aruba, where the weather forecast based on experience from past years was the most favorable along the eclipse path, which was thousands of miles long but only about a hundred miles wide. One experiment studied the heating of the solar corona to its temperature of millions of degrees through a search for high-frequency oscillations in loops of coronal gas held in place by magnetic fields. Timothy McConnochie `98 wrote his senior thesis on the subject, and operated the equipment on site along with Bryce Babcock, Staff Physicist and Coordinator of the Bronfman Science Center. The experiment was supported by a grant from the National Science Foundation. A second experiment was aimed at mapping the temperature of the solar corona. Supported by the National Geographic Society, it was operated on site by Lee Hawkins of Wellesley College, the Keck Consortium technician; and by Carolina Artacho Guerra of Bryn Mawr College, a student participating through the Keck Consortium. A third experiment was aimed at linking the eclipse observations with observations from the Solar and Heliospheric Observatory spacecraft; it was supported by the National Geographic Society and by NASA. Pasachoff developed this observational plan in collaboration with Guenter Brueckner of the Naval Research Laboratory, Principal Investigator of one of the telescopes on SOHO. Operated on site by S. Martin, the data were circulated in a press release by NASA in the hours following the eclipse, and then were studied further at Williams by Johan Kongsli `98, a senior doing an independent project. Students participating in setting up these telescopes and computers and in other aspects of the expedition included James Bates `98, Mac Stocco `98, Laura Brenneman `99, Craig Westerland `99, and exchange student Lisa Reinker `99. These students were the only undergraduates to be part of scientific eclipse expeditions. Collaborating staff included Babcock, Martin, and Hawkins, as well as Jonathan Kern, now optical scientist at the Laser Interferometer Gravitational Observatory at Caltech, who built equipment that was important for the experiments. Also collaborating was Robert Eather, who made an IMAX movie of the eclipse. In the summer of 1998, the data from all the eclipse observations were further studied by Kevin Russell `00, by Keck Summer Fellow Ben Knowles of Vassar, and by McConnochie. (See http://www.williams.edu/Astronomy/eclipse98.)
We are now planning scientific experiments for the 11 August 1999 eclipse that will cross Europe. Pasachoff has already received a grant from the National Science Foundation for the oscillation experiment. Two other proposals have been sent to NASA for observations in coordination with the Solar and Heliospheric Observatory spacecraft observations. Pasachoff is advising the Observatory of the National Academy of Sciences of Romania about the use of their telescopes at the 1998 eclipse, and is expecting to observe the eclipse from Romania (See website at http://www.williams.edu/Astronomy/eclipse99.)
A scientific paper that arose from observations that used the eclipse equipment to monitor the occultation of a star by Neptune's moon Triton has appeared in Nature, in the 25 June 1998 issue. Pasachoff, Babcock, and McConnochie `98, are among the co-authors of the paper, whose first author is James Elliot of MIT. The paper, entitled "Global Warming on Triton," deals with joint results from our observing site in Hawaii and from the Hubble Space Telescope. The National Geographic Society gave two supplemental grants for these Triton observations, and Babcock and McConnochie participated in the expeditions to Australia in August 1997 and to Hawaii in November 1997, respectively.
January 1998 brought the publication by Pasachoff in collaboration with Prof. Roberta J. M. Olson of Fire in the Sky: Comets and Meteors, the Decisive Centuries, in British Art and Science (Cambridge University Press, 1998). The book marks the culmination of a decade of research, which started with grants from the National Endowment for the Humanities and peaked with grants from the Getty Grant Program. Pasachoff is the only physical scientist to have received grants from either source. Olson is Professor of Art History at Wheaton College; the two were introduced by Prof. Sam Edgerton, now Professor Emeritus of Art, in 1986 at the time of Halley's Comet.
By invitation for the first volume of the Journal for the History and Heritage of Astronomy, Pasachoff has written about the "Hopkins Observatory: Oldest Extant Observatory in the United States." This paper should become the standard reference on the history of astronomy at Williams, superseding "Early American Observatories" by Prof. Willis Milham, published in 1938.
Pasachoff has been appointed Carter Lecturer by the Carter Observatory, New Zealand, for 1998, and is undertaking a lecture series in eight New Zealand cities in December. He served as Chair of the Astronomy Division of the American Association for the Advancement of Science and chaired and organized a session on the latest NASA results at the general meeting in Philadelphia during February 1998. He is now Retiring Chair, and is organizing a session for the January 1999 annual meeting in Anaheim. He completed his term as American Physical Society/American Institute of Physics Member at Large of the Forum on Education [Executive Committee], attending their sessions at APS meetings. Pasachoff continues as President of the Williams College Chapter of Sigma Xi.
In his eclipse work, Pasachoff was busy not only on scientific tasks but also on educational tasks relevant to the safe observing of the eclipse by populations across the Americas, through his roles as Chair of the Working Group on Eclipses of the International Astronomical Union (IAU) and as Chair of the Subcommittee on Public Education through Eclipses of the Commission on the Teaching of Astronomy of the IAU. (See http://www.williams.edu/Astronomy/IAU_eclipses.)
Pasachoff is revising his Field Guide to the Stars and Planets, preparing the fourth edition. A 1998 update of the third edition, with tables and graphs valid through the year 2000, was published (Houghton Mifflin Co.) He also worked on several encyclopedia contributions: "Planets" and "Solar System" for World Book, 1998; "Olbers's Paradox," "Steady-State Theory" and "Big-Bang Theory" for Encarta 98 (Microsoft, CD-ROM).
Pasachoff continues on the science board of the World Book and as consulting editor for astronomy of the McGraw-Hill Scientific Encyclopedia and Yearbooks. He continues on the advisory board of Odyssey, an astronomy magazine for children.
Pasachoff did a book review entitled "Ancient Eclipses and the Rotation of the Earth" by F.R. Stephenson for Isis, an interdisciplinary contribution.
Kwitter and colleagues are continuing their studies of planetary nebulae - glowing gossamer shells of gas ejected by dying stars. (See http://oposite.stsci.edu/pubinfo/pr/97/pn/.)
The chemical composition of these extraordinarily beautiful and complex objects yields important clues as to the nature of the nuclear processing that went on inside the parent star. These stars, which make up the majority of those in our Milky Way Galaxy, have masses between about 0.8 and 10 times the mass of our Sun. In addition to the evolutionary history of their progenitors, planetary nebulae as a class offer an opportunity to study the properties of the surrounding interstellar medium and the chemical evolution of the Galaxy as a whole.
Kwitter's main collaborator is Dick Henry (U. Oklahoma), with whom she is finishing a new determination of carbon abundances in planetary nebulae. They have used newly recalibrated archived data from the International Ultraviolet Explorer satellite to study the production of carbon in stars that produce planetary nebulae. Honors student Jim Bates `98 and summer 1997 Keck exchange student Kerrie McKinstry (Wellesley College `99) contributed to this project by analyzing spectra from dozens of planetary nebulae. As an adjunct to the ultraviolet observations, Kwitter and Henry obtained optical spectra on two observing runs at Kitt Peak National Observatory, using the 2.1 meter telescope and Goldcam CCD spectrograph.
In collaboration with Bruce Balick (U. Washington), Kwitter and Henry observed in New Mexico with the Apache Point Observatory 3.5-meter telescope and dual imaging spectrograph in May 1998. Astrophysics major Sara Kate May `00 also participated in this observing run. Kwitter, Henry and Balick are working on a multi-faceted project to study planetary nebulae as individual objects and as probes of chemical evolution in the Galaxy (and possibly in other galaxies as well). They have submitted an NSF grant for support of this project.
Summer students working with Kwitter in 1998 include James Bates `98 and Leila Zelnick `00 as well as Keck Summer Fellow Kelli Corrado, Colgate `99.
Kwitter taught a new course, ASTR 211, to majors about data reduction and image processing methods, involving intensive use of the Department's network of DEC Alpha workstations. A new course in the spring semester, ASTR 334, was on the Hubble Space Telescope. Taught by Pasachoff, it attracted 67 students, largely upperclass students. Pasachoff also taught a junior/senior tutorial on the solar corona, ASTR 408T. Kwitter developed a new course, ASTR 418, Astrophysics of the Milky Way and Other Galaxies, to be taught in Spring 1999.
Kwitter continues her term on the Space Sciences panel of the National Research Council Associateship Programs Review. The NRC is the principal operating agency of the National Academy of Sciences and National Academy of Engineering, and awards postdoctoral and senior associateships at national facilities. With co-author Steven Souza, she is working on a project for J. Weston Walch publishers, writing hands-on learning manuals for high-school physical science classes.
Under the guidance of Steve Martin, the 24" telescope and auxiliary telescopes continue to be used in support of the astronomy curriculum. Over 150 introductory astronomy students completed over 900 observations of celestial objects over the course of the academic year. These included observations, photographs, and CCD images of the sun, moon, stars, nebulae, and galaxies.
Martin developed Web pages for each of the introductory astronomy courses. These pages contain links to useful astronomy sites and provide a forum for students to display images that they have taken with the observatory's CCD system and with photographic cameras as part of their observing projects.
Student roof TA's, responsible for operating the telescopes, participating in the research projects, and assisting introductory students with assignments, included Rebecca Cover `00, Laura Brenneman `99, Daniel Seaton `01, Robert Lyman `99, Mithandra Stockley `01, Robert Wittenmyer `98, Christopher Spence `00, and Daniel Anello `98.
On February 26, 1998, when most Williams astronomers and astronomy students were at the total eclipse in Aruba, alumna Christie Reynolds `97, now a graduate student in Astrophysics at Dartmouth, supervised observation in Williamstown of the 18% partial eclipse that was visible.
The Milham Planetarium was run by Mac Stocco `98 and by Jim Bates `98. The fall show was "The Beauty of Mars." In the spring semester, Stocco wrote a new show: "A Total Solar Eclipse!" Summer shows were given by the summer research students, on "The Sky Tonight."
Andrea Dupree of the Harvard-Smithsonian Center for Astrophysics, President of the American Astronomical Society, spent several days on campus giving talks and meeting with students. She was a Bernhard Visiting Fellow. Her public lecture was entitled "Gone With the Wind: Mass Loss from the Sun and Stars."
Daniel Britt of the Lunar and Planetary Laboratory, University of Arizona, Project Scientist for the Imager for Mars Pathfinder (IMP) camera that landed on Mars in the summer of 1997, spoke about the results.
Students doing research gave talks, including James Bates `98 on his planetary nebulae work; Johan Kongsli `98 on the link of eclipse observations with the SOHO coronagraph in space; and Timothy McConnochie `98 on the coronal oscillation eclipse experiment.
Dr. Andrea Dupree
Prof. Karen B. Kwitter
Prof. James B. Kaler
Dr. Dan Britt
Dr. Andrea Dupree
Prof. Jay M. Pasachoff