CSR conducts an active program of research in astronomy, astrophysics, space science, and related technology, with emphasis on experimental and theoretical investigations in support of various National Aeronautical and Space Administration (NASA) flight missions. Specific areas of research include gravity-wave, X-ray, optical, radio, and radar astronomy; theoretical and experimental space plasma physics; planetary surfaces and atmospheres; and the space life sciences. CSR is heavily involved in the following ongoing or upcoming NASA missions: Voyager, the Japanese-US ASCA satellite, the Rossi X-ray Timing Explorer (RXTE), the WIND mission, the High-Energy-Transient Experiment (HETE), the Advanced X-ray Astrophysics Facility (AXAF), and the Shuttle-MIR program. CSR also supports MIT participation in the Laser Interferometer Gravity Wave Observatory (LIGO), the Michigan-Dartmouth-MIT (MDM) Observatory, and the Magellan Observatory. CSR supports investigators in the Space Engineering Research Center and administers a program of theoretical astrophysics and space plasma physics and of optical observations carried out using ground and space observatories. Much of the research carried out in CSR is reported by the following departments: Physics, Earth Atmospheric & Planetary Sciences, and Aeronautics & Astronautics.
The Bruno B. Rossi X-ray Timing Explorer (RXTE) was successfully launched from Cape Canaveral on Dec. 30, 1995. It carries two MIT-built instruments, a sophisticated Experiment Data System (EDS) and a sky-scanning All Sky Monitor (ASM), prepared at CSR under the direction of Prof. H. Bradt with Drs. A Levine and W. Mayer. NASA named the mission in honor of the late MIT Professor Rossi who was one of the founders of the field of x-ray astronomy. By the end of June, RXTE had already observed 160 celestial X-ray sources. Results include discovery of a remarkable pulsar/burster (Prof. W. Lewin), the discovery of extremely rapid ~1000 Hz quasi-periodic oscillations from several neutron-star binary systems (Dr. E. Morgan, Prof. W. Lewin), and elucidation of the very rapid fluctuations of "micro-quasars" in our Galaxy (Prof. Bradt and Dr. R. Remillard). The MIT ASM is tracking the intensities of the brightest ~70 sources in the sky and alerts the scientists to any unusual temporal variability in such a source, or to the appearance of a new source.
CSR has been participating in the operations planning, calibration, and data analysis of ASCA, a Japanese/US X-ray astronomy satellite which was launched in 1993 and carries CSR's CCD X-ray detectors (developed in collaboration with Lincoln Laboratory). MIT personnel are participating in numerous astronomical projects, including studies of the diffuse X-ray background, supernova remnants, clusters of galaxies and distant quasars (Drs. G. Ricker & M. Bautz).
This year MIT joined the Magellan project, together with the Carnegie Institution of Washington, Harvard University, and the Universities of Arizona and Michigan. Two nearly identical 6.5 meter diameter optical telescopes are being constructed on Cerro Las Camapanas in Northern Chile, with the first scheduled for completion in late 1998. CSR is administering MIT's participation (Profs. C. Canizares & P. Schechter).
MIT also continues its active participation in the Michigan-Dartmouth-MIT Observatory consortium. A major survey has been completed of very accurate galaxy distances derived using the novel surface-brightness fluctuation technique, leading to a new determination of the cosmologically important Hubble parameter (Prof. J. Tonry), and new advances have been made in the study of time delays in gravitationally lensed quasars, which also constrain the Hubble parameter (Profs. J. Hewitt & P. Schechter).
MIT's interplanetary plasma experiment on the Voyager spacecraft is now 49 Astronomical Units from the sun and heading toward the edge of the solar system. Contrary to expectations the solar wind has a great deal of structure even at these large distances. A newly discovered velocity oscillation with a period of 1-2 days must be locally generated (Prof. J. Belcher & Dr. J. Richardson).
Further analysis of the anomalous microwave scattering properties of regions on the surface of Venus, measured with the Magellan mission, have led to the surprising possibility that these may result from concentrations of the trace element tellurium within a certain altitude range on the planet (Prof. G. Pettengill & Dr. P. Ford).
The joint Caltech/MIT LIGO (Laser Interferometer Gravitational-wave Observatory) project is currently at the peak of its construction phase. Contracts have been let for major components and the building designs are out for bid. The two 4km slabs for the beam tubes have been poured at the Hanford, Washington site while the clearing and leveling has been completed at the Livingston, Louisiana site (Prof. R. Weiss & Dr. D. Shoemaker).
Theoretical investigations include: the development of a new, fast method for computing the power spectrum of microwave background anisotropies, which is a key diagnostic of cosmological models (Prof. E. Bertschinger); supercomputer simulations of the hydrodynamics of binary star coalescence (Prof. F. Rasio); studies of the evolutionary histories of millisecond pulsars in binary star systems (Profs. S. Rappaport & P. Joss); and investigations of the ages of the oldest stars in globular clusters (Prof. Joss). Closer to Earth, a theory for a global, kinetic, photoelectron-driven polar wind successfully accounts for nearly all the recently observed novel features in the "polar wind" of the Earth's Magnetosphere (Dr. T. Chang).
In the area of aerospace technology, an Advanced Dynamic Load Sensors Experiment has been installed on the MIR space station to assess the impact of human space activity on the space station (Prof. D. Newman). A new method was developed for improving the precision and reliability of positioning aircraft during runway approaches using GPS signals (Prof. Counselman) and flight simulator research in cockpit displays for GPS instrument approaches is also underway (Dr. C. Oman). The Space Microstructures Laboratory in CSR continues to develop new techniques for fabrication of precise micro- and nano-structures for space astronomy and other applications (Dr. M. Schattenburg).
The High Energy Transient Experiment (HETE), which will search for bright transient emissions from astronomical objects over a very broad energy interval from the UV to gamma rays, is in final preparation at CSR for launch in the fall of 1996 (Drs. G. Ricker).
AXAF is a major NASA mission of the "great observatory" series, scheduled for launch in 1998. Two of the four major instruments, the High-Energy Transmission Grating Spectrometer (Prof. Canizares) and the AXAF Charge-Coupled Device (CCD) Imaging Spectrometer (Drs. Ricker & Bautz), are entering final construction and test at CSR and will be delivered to NASA for final calibration during the coming year. CSR is also helping to establish the AXAF Science Center, which will oversee the operation of AXAF during the mission (Prof. Canizares).
An experiment for the 1998 "Neurolab" mission is now starting the active development phase. Ground based research on human spatial orientation in real and virtual environments, tactile cueing systems continues, EVA biomechanics, and a new research initiative on artifical gravity physiology and human factors has begun (Profs. L. Young & D. Newman, Dr. C. Oman).
Claude R. Canizares
MIT Reports to the President 1995-96