MIT Reports to the President 1998-99


The George R. Wallace, Jr., Astrophysical Observatory is a teaching and research observatory located in Westford, Massachusetts. Observing facilities consist of two domes containing a 24-inch reflecting telescope and a 16-inch reflecting telescope, a 4-bay shed with roll-off roof housing three Celestron 14-inch Cassegrain telescopes as well as a 5.5-inch astrograph, and several Celestron 8-inch Cassegrain portable telescopes. Additional infrastructure includes a building housing workshop, darkroom, computer facilities, and observers' quarters. The primary workhorse instrument for the 24-inch telescope has been a portable high-speed CCD camera system [PCCD] mated to a custom optics box providing 5:1 field compression at the Cassegrain focus. All other telescopes are equipped with CCD (charge-coupled device) camera systems and dedicated control computers.

Last year, course 8.287J-12.410J (Observational Techniques of Optical Astronomy) drew 15 students, who used the Wallace facilities for a variety of astronomical projects, including broadband imaging of star clusters to construct color-magnitude diagrams and moderate temporal resolution photometric imaging of asteroid lightcurves to deduce rotational characteristics. For subject 12S23-12.409 (Observing the Stars and Planets, the first subject number distinguishes first-year vs. upper-class registrants), an additional 14 students used the Observatory for laboratory work. Several field exercises were also conducted for course 12.401 (Beyond the Solar System; 10 students).

Over the past year, the PCCD has been used at the 24-inch to continue obtaining high-quality astrometric image scans of the star fields through which Pluto and Neptune's moon Triton will cross over the next decade. The astrometric data has been used to identify stars that these two bodies will occult and assess where the occultation path will be visible on the Earth to facilitate the planning of observing campaigns. Stars that were identified as probable occultation candidates were further observed to determine their apparent colors and magnitudes. The eventual occultation data will be used to investigate how the thin nitrogen atmospheres of Pluto and Triton respond to changes in season and distance from the sun. This project has been carried out by Steve McDonald, Michael Person, and several summer UROP and REU students under the overall supervision of Dr. David Osip and Professor James Elliot. Dr. Steven Slivan (working with Prof. Binzel) continued a long-term project of broadband photometric imaging of asteroid lightcurves. Several undergraduate students have participated in the asteroid program and one student is currently completing the observational component of her undergraduate thesis.

Professor James Elliot and Dr. David Osip (along with masters student Adam Gould) continued a collaboration with Professor Paul Schechter on the design of the MAGIC CCD camera for the Magellan telescopes in Chile, of which MIT has a 10 percent share of the observing time. Specifically in the past year, Mr. Gould completed his masters thesis in computer science designing a three tier execution kernel for a modular telescope and instrument control system to be used by the MAGIC camera. Current plans are to use Wallace Astrophysical Observatory as a local test-bed for MAGIC implementation prior to bringing the camera to Chile.

On-site computing facilities have been upgraded to allow direct file transfer of imaging data from the telescopes to either lab computing facilities for project data or to class ‘lockers' for various class data. Software and hardware upgrades has been added to allow for on site data reduction and analysis in near real time. Plans are continuing for a permanent replacement to the portable CCD system. Finally, a new guide-camera system has been installed to allow for accurate long exposures of faint objects.

Prof. James Elliot, Observatory Director, was on sabbatical leave at Lowell Observatory for the past year. Dr. David Osip joined the observatory staff as a Research Scientist in August of 1998 and with the assistance of Dr. Heidi Hammel during a transition period, he has served as Interim Manager in the absence of Prof. Elliot. Additional assistance with site management and facilities maintenance has been provided by Research Specialist Richard Meserole. Mr. Person has served as a part-time Technical Assistant for student training, observing, and data analysis. Mr. McDonald continued his part-time work on software and computer management. Dr. Slivan has assisted with supervision of summer student activities related to asteroid lightcurve programs. Undergraduates working on the various projects were funded in part by NSF's Research Experiences for Undergraduates (REU) program and in part by NASA and NSF research grants to Prof. Elliot and Dr. Osip.

David J. Osip

MIT Reports to the President 1998-99