MIT Reports to the President 1994-95

George R. Wallace, Jr., Astrophysical Observatory

FACILITIES

The George R. Wallace, Jr., Astrophysical Observatory is a teaching and research observatory located in Westford, Massachusetts. Its facilities consist of a 24-inch telescope, a 16-inch telescope, several 14- and 8-inch telescopes, a 5.5-inch astrograph, and a building that houses a workshop, darkroom, computer facility, and observers' quarters. Instruments include the SNAPSHOT high-speed dual-CCD photometer, a portable high-speed CCD occultation system, several small CCD systems, conventional photometers, photographic cameras, and a spectrograph. Upgrades to Observatory facilities during the past year included re-engineering of the drive systems for the 14- inch telescopes and characterization of the 24-inch drive system to minimize periodic errors. The spectrograph was successfully converted from 35-mm film to CCD technology; work is continuing to improve the system optics.

PERSONNEL

Professor James L. Elliot continued his duties as Observatory Director. Principal Research Scientist Heidi B. Hammel assists with site management and telescope scheduling, with the help of Research Specialist Rich Meserole. Mr. Michael Mattei serves as a part-time Technical Assistant for making on-site observations and helping with optical maintenance. Other staffing (usually students) is coordinated through research programs. The undergraduate working on the spectrograph project--Asantha Cooray--is participating in the Undergraduate Research Opportunities Program (UROP); other students are supported in part by NSF's Research Experiences for Undergraduates.

ACADEMIC ACTIVITIES

Last year course 8.287J-12.110J (Observational Techniques of Optical Astronomy) drew 12 students, who used the Wallace facilities for a variety of astronomical projects. An additional 11 students in subject 12S23 (Observing the Stars and Planets) used the Observatory for laboratory work. Course 12S24 (Advanced Observations of Stars and Planets) was not offered this year. An informal field trip for course 12.401 (Beyond the Solar System) was offered, as was an observing session for freshmen last fall. An open house held during MIT's 1995 Independent Activities Period attracted over 40 people (mostly undergraduates; some faculty and staff from other departments came).

RESEARCH PROGRAMS

Ms. Reba Bandyopadhyay, Mr. Stephen McDonald, and graduate student Catherine Olkin used the 24- inch to obtain CCD data for astrometric fields surrounding the comet 2060 Chiron and the star Ch08, which Chiron occulted in March 1994. Professor Elliot, Ms. Olkin, and their colleagues successfully observed the occultation with NASA's Kuiper Airborne Observatory, and they found several features that may be signatures of jets from Chiron's nucleus. Mr. McDonald, Ms. Bandyopadhyay, and Ms. Olkin also used CCD data from the 24-inch for astrometric and photometric observations of occultation candidate stars for future events involving Pluto, Saturn, Jupiter, Uranus, Neptune, Triton, and Titan. Astrometric and photometric observations in support of the Hubble Space Telescope are continuing, with Dr. Amanda Bosh (Lowell Observatory) assisting in coordination of that effort.

Former graduate student Steve Slivan, working with Professor Richard Binzel and undergraduate Adam Ross, used the 24-inch to observe rotational lightcurves of asteroids Lacrimosa, Dresda, Urda, Florentina, Claudia, Eriphyla, Koronis, and Elvira. Dr. Slivan developed an extensive database of asteroid photometry using the Wallace facilities, and recently successfully defended his MIT doctoral dissertation based on Wallace data.

Graduate student Jeff Foust used the 24-inch and 16-inch telescopes to prepare the portable high-speed CCD system for observations of the collision of Comet Shoemaker-Levy 9 with Jupiter, which occurred in mid July 1994. Mr. Foust observed this event using the system on the Mauna Kea Planetary Patrol Telescope (Hawaii). Ms. Bandyopadhyay and undergraduate Lisa Sopata monitored the event at Wallace using the SNAPSHOT on the 24-inch.

Mr. McDonald and Ms. Olkin are using the 24-inch to obtain CCD data for the astrometric fields surrounding: Pluto and the star P28 (which Pluto will occult in July 1995); Neptune's moon Triton and the star Tr148 (which Triton will occult in August 1995); and Saturn's moon Titan and star GSC5254-00997 (which Titan will occult in August 1995). The data will be analyzed to refine pre-event predictions of the positions of the stars and occulting objects. Professor Elliot, Dr. Hammel, Ms. Olkin, and colleagues have been awarded time on the NASA Infrared Telescope Facility (Mauna Kea, Hawaii) to observe the August occultation events.

Heidi B. Hammel

MIT Reports to the President 1994-95