Pasachoff conducted an expedition to India for the total solar eclipse of 24 October 1995, in collaboration with Bryce Babcock and Kevin P. Reardon `92. Babcock is Staff Physicist and Coordinator of the Bronfman Science Center. Reardon, then on the solar-physics staff of the Institute for Astronomy of the University of Hawaii is now at the Capodimonte Observatory in Naples, Italy, working with the Themis Solar Telescope from the Canary Islands. The expedition included students Sebastian Diaz `98; Keck-Foundation exchange students Rana Nichols-Kiley, Vassar `98; and David Berger, Colgate `98; and Eric Kutner, Princeton `95; Lee Hawkins, Instructor at Wellesley College and Keck Technician; Jonathan Kern; and Dr. Robert Eather. The experiments were devoted to studying the solar corona, addressing the problem of how the corona is heated to two million degrees kelvin. They conducted a search for for high-frequency oscillations in the magnetic field that could cause the coronal heating. A special optical train was used with a 14 inch telescope and beamsplitter to capture side-by-side images of the corona on individual frames of a Princeton Instruments CCD at a 5Hz rate. One image was taken at the wavelength of a coronal emission line, and the other at a nearby band of the continuum spectrum. In a separate experiment to map coronal temperatures, they observed the corona through several filters at ultraviolet wavelengths specifically chosen to maximize or minimize the differences between the coronal and photospheric spectrum; the data were recorded and digitized with a Photometrics CCD.
The expedition was carried out in Mukundgarh Fort, Rajasthan, India in favorable weather. The data will be studied during the summer of 1996.
During the summer of 1995, Diaz and Nichols-Kiley studied the data from the total solar eclipse of 1994, which a Williams expedition observed from Putre, Chile. The data are also being studied by Reardon. A joint paper is in the final stages of preparation. Preliminary results were reported at the San Antonio meeting of the American Astronomical Society in January 1996.
Pasachoff continued his work with Prof. R.J.M. Olson of Wheaton College on images of comets in British Art, with support from the Getty Grant Program. They completed the manuscript for a book on this subject.
Pasachoff continued his positions as U.S. National Representative to Commission 46 (The Teaching of Astronomy) of the International Astronomical Union and chair of a new subcommittee on public education on the occasions of solar eclipses; and as Chair, Working Group on Eclipses of Commission 12 (The Radiation and Structure of the Solar Atmosphere) of the International Astronomical Union.
He served on the Scientific Organizing Committee of a NATO Advanced Research Workshop, Theoretical and Observational Problems Related to Solar Eclipses, at Sinaia, Romania, in June 1996. He delivered papers on solar coronal research, on future eclipses, on public education on the occasion of eclipses, and on first results from the Solar and Heliospheric Observatory (SOHO) spacecraft.
He served on the advisory boards of American Association of Variable Star Observers educational project Hands-On Astronomy (NSF Curriculum Grant); Astronomical Society of the Pacific (NSF Curriculum Grant A-ASTRO); Odyssey, a children's magazine (Cobblestone Publishing); and World Book Encyclopedia; and he continued as consulting editor for the McGraw-Hill Encyclopedia of Astronomy.
He continued as a Sigma Xi National lecturer. As such, he lectured on "The Triumph of the Hubble Space Telescope" at Quinnipiac College, the University of Hawaii at Hilo, and the University of Hawaii at Manoa. He gave the Phi Beta Kappa colloquium on "The Sun and Solar Eclipses" at the University of Massachusetts at Amherst.
Kwitter's main projects includes the chemical abundance of planetary nebulae, and interactions of old planetary nebulae with the interstellar medium. Her studies with Richard Tweedy (Steward Observatory, University of Arizona) culminated in the paper entitled "An Atlas of Planetary Nebulae and Their Interaction with the Interstellar Medium," to be published in November 1996 in the Astrophysical Journal Supplement Series. This paper includes images taken with the large-format (2048x2048 pixel) CCD detector at the Burrell Schmidt telescope on Kitt Peak, Arizona.
Kwitter is continuing to work on carbon abundance in planetary nebulae. The only emission line appearing in the visible part of the spectrum is a transition in singly ionized carbon, C+, which is intrinsically very weak compared to the normally observed emission lines in these object; there are stronger lines available in the ultraviolet. Along with Richard Henry (University of Oklahoma) and his graduate student Richard Buell, Kwitter is working under the auspices of a NASA Astrophysics Data Program grant to use newly recalibrated archived data from the International Ultraviolet Explorer satellite to study the production of carbon in intermediate-mass stars. Summer 1995 Keck exchange student Dan Pierkowski (Colgate University `96) and Tim McConnochie `98, continued the work of their predecessors. As an adjunct to the ultraviolet observations, Kwitter and Henry obtained optical spectrophotometry with the Kitt Peak National Observatory 2.1-m telescope, using the Goldcam CCD spectrograph. Tim McConnochie accompanied Kwitter, Henry, and Henry's graduate student on that observing trip.
Kwitter served as Chair in her final year as a member of the Electorate Nominating Committee of Section D on Astronomy, of the American Association for the Advancement of Science.
Maraziti continues her dissertation research on galaxy clusters. Certain moderate to high redshift galaxy clusters appear to have an excess of galaxies with blue optical colors when compared to low redshift clusters of comparable richness (the "Butcher-Oemler Effect"). Most attribute the blue color to enhanced star formation, but the trigger that accelerates the star formation in these galaxies is not understood. She is observing the galaxies in three clusters at infrared wavelengths to search for evidence that galaxy-galaxy interactions trigger the star formation and to investigate whether their star-forming properties are similar to those of nearby star-burst galaxies. This work is under the direction of Robert Joseph and Patrick Henry at the University of Hawaii. All infrared data for this project must be collected at the high and dry location of the UH 2.2 meter telescope on top of Mauna Kea on the Big Island in Hawaii. She was awarded two nights in November 1995 and three nights in June 1996. Presently, she is reducing the data on the Williams Astronomy Department workstations; the preliminary results look promising. In one of the clusters, she has seen no evidence for the Butcher-Oemler effect in the infrared colors. This suggests that if star formation is responsible for the blue optical colors of the cluster galaxies, then that star formation may be different than the star formation of galaxies in less crowded environments.
Her infrared images and photometry of a tremendously violent interacting galaxy system, IIZw96, will be submitted to be published in the Astronomical Journal later this year, in a paper authored by Goldader et al. (Space Telescope Science Institute).
New observations by the Hubble Space Telescope and others show that the universe is filled with many more small, faint galaxies than anticipated. The origin of these galaxies is a mystery. Until recently, little attention has been paid to the tremendous potential of galaxy-galaxy collisions to clutter the universe with fragmented star clusters -- galaxies by their own rights. Maraziti is interested in exploring the outer regions of colliding galaxies to search for such self-gravitating groups of stars in the process of breaking free from their parent systems. Jennifer Heldman (Colgate `95), a student on KNAC exchange to Williams for the summer, observed 6 systems for this project.
The Department was pleased to receive an NSF Academic Research Infrastructure grant, which, along with matching funds from the College, funded a DEC Alpha workstation, X terminal and an upgrade to the 24" telescope control system, focus apparatus, and filter wheel.
Led by D. Maraziti, the Hopkins Observatory continued two long-term research projects: assembling a photometric CCD atlas of peculiar galaxies and searching for optical counterparts to gamma-ray bursts. The systematic lack of identification of gamma-ray burst counterparts at other wavelengths remains one of the great frustrations in astronomy. To address this issue, a group of investigators on the Compton Gamma Ray Observatory has formed a collaborative effort called the "Rapid Burst Response Campaign." The Hopkins Observatory is now one of about 50 sites worldwide that are part of this network. The TA's and Maraziti are on-call constantly to observe burst sites at a moment's notice. Unfortunately, no bursts with favorable observing positions occurred this semester.
Over 150 introductory students used the observatory this year to complete a total of nearly 800 projects. These included daytime solar observations, pre-dawn comet observations, and evening observations of stars, nebulas, and galaxies.
Student roof TA's, responsible for operating the telescope, participating in the research projects and assisting introductory students with assignments, included Nathaniel Farny `96, Robert Galloway `96, David Jaskoski `97, Christina Reynolds `97, Patrick Russell `97, Daniel Annello `98, Tim McConnochie `98, Robert Wittenmeyer `98, Samuel Young `98, Ned Augenblick `99, Blake Bear `99, Laura Brenneman `99, Erik Klemetti `99 and Craig Westerland `99. Sebastian Diaz `98 volunteered as System Manager for the astronomy workstations.
Maraziti traveled to Colgate University and Swarthmore College in fall 1995 as a part of the Keck faculty exchange program to deliver a lecture about interacting galaxies and consequences.
One of Maraziti's goals is to maintain a sizable amount of contact with those outside of the college community who have an interest in astronomy. Last summer, she delivered another version of the interacting galaxies talk to two groups of amateur astronomers, one to the Arunah Hill Club in Cummington, Massachusetts, and the other to the Rockland Astronomy Club (from New York, but they met at a campsite in Massachusetts). The Hopkins Observatory hosted a large number of public observing sessions this year, especially in conjunction with the fortuitous appearance of the bright comet Hyakutake. In June 1996, Jay Pasachoff and Maraziti ran a day-long workshop to show teachers of local schools the basics of obtaining astronomical images via the world-wide web and other computer resources. Maraziti is an active pen-pal scientist in the Science-By-Mail program sponsored by the Boston Museum of Science and regularly corresponds with six groups of elementary school children throughout the United States.
This year `s show at the Milham Planetarium was entitled "The New Planets." Shows were presented by Jason Lorentz `96 and Christina Reynolds `97. They gave more than 80 presentations during the year. Woody Printz, department volunteer, also presented several shows. Summer shows were given by Mac Stocco `98, Aditi Rao `99 (Wellesley College), Karla Solheim `98 (Bryn Mawr College), and Christy Reynolds `97.
Williams had a strong showing at the 6th annual Keck Northeast Astronomy Consortium student conference, held at Vassar College in October 1995, at which students reported on their research activities during the previous summer. During the summer of 1996, the following Keck exchange students are in residence at Williams: Aditi Rao (Wellesley `99) working with Karen Kwitter; Karla Solheim (Bryn Mawr `99) working with Deborah Maraziti and Stephan Martin; Matthew Pickard (Colgate `98), working with Jay Pasachoff.