MIT Reports to the President 1997-98
CSR conducts an active program of research in astronomy, astrophysics, space science, and related technology, with emphasis on 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 several ongoing or upcoming NASA missions and supports MIT participation in several major research facilities. Research carried out in CSR is reported by the following departments: Physics, Earth Atmospheric & Planetary Sciences, and Aeronautics & Astronautics.
The orbiting Bruno B. Rossi X-ray Timing Explorer (RXTE), named in honor of late MIT Prof. Rossi, is in its third year of successful observations. The All Sky Monitor (ASM), one of two instruments prepared at CSR, records long-term intensity variations in some 100 X-ray sources revealing new phenomena like superorbital periods and recurring transients. Discovery of simultaneous radio, infrared, and X-ray outbursts from the galactic black-hole systems called "microquasars" show evidence of the disappearance of a portion of the accretion disc during formation of relativistic jets of ejecta. In other systems, X-rays are probing strong-field General Relativity and may show the signature of a spinning black hole. The discovery and subsequent studies of oscillations in X-ray flux at kiloHertz frequencies have demonstrated that neutron-star binary systems are the precursors of the famed millisecond radio pulsars. RXTE has also helped identify and study several gamma ray bursters (Profs. Bradt and Rappaport, Drs. Levine, E. Morgan, R. Remillard, W. Cui, D. Chakrabarty). In related activities, Prof. W. Lewin continues his study of quasi-periodic oscillations of low-mass X-ray binaries. CSR's CCD X-ray detectors (developed in collaboration with Lincoln Laboratory) continue to operate well on the Japanese ASCA satellite. Investigations of galaxy clusters, active galactic nuclei, supernnova remnants X-ray binaries, and active stars have also been pursued using data from ASCA and the ROSAT satellites (Prof. C. Canizares, Drs. D. Davis, K. Flanagan, J. Houck, D. Huenemoerder, H. Marshall, D. Schultz and M. Wise).
Prof. J. Hewitt has initiated a new radio survey for gravitational lenses in the southern sky; and she has preliminary measurements of a time delay in a previously known lens 0218+357 which could provide another independent measurement of the Hubble constant. Prof. V. Kaspi is involved in a major survey of radio pulsars in the southern Galactic plane, which is only 10% complete but has already found 130 new pulsars. She has also discovered a 69 ms pulsar near the supernova remnant RCW103.
In optical astronomy MIT is a member of the Magellan Project consortium, which is building two 6.5 meter diameter optical telescopes on Cerro Las Camapanas in Northern Chile, the first scheduled for completion in 1999. Construction of enclosure and fabrication of the telescope structure are nearly complete, and polishing of the mirror is underway, and planning has begun for an MIT camera to be permanently mounted on one of the telescopes (Profs. Canizares, J. Elliot & P. Schechter, Dr. H. Hammel). Hubble Space Telescope images in the IR of stars in their final death throes show remarkable structure depending on the circumstellar environment (Dr. J. Kastner).
The interplanetary plasma group monitors solar wind conditions from three spacecraft, two near Earth (IMP 8 and WIND) and one over 50 Astronomical Units away (Voyager 2). Voyager 2 is seeing a decrease in solar wind pressure as it approaches the termination shock in the outer solar system; the phenomenon is being modeled with 2-D hydrodynamics. As we approach solar maximum in ~2001, IMP 8 and WIND continue detecting "space weather" events, which can affect satellites, terrestrial communications and electric power grids (Prof. J. Belcher, Drs. A. Lazarus, J. Richardson, J. Steinberg, Ms. K. Paularena).
The Mars Global Surveyor (MGS) was successfully placed in orbit around Mars this year. The Mars Orbiting Laser Altimeter (MOLA) experiment on board has been returning precision data on the planet's surface, including the discovery and analysis of immense clouds of carbon dioxide ("dry") ice, covering much of the northern polar cap. (Profs. G. Pettengill, M. Zuber, Dr. P. Ford).
Construction of the Caltech/MIT LIGO (Laser Interferometer Gravitational-wave Observatory) continues on schedule and budget at the Livingston, Louisiana and Hanford, Washington sites, with observations to start in 2001. The two L-shaped 4x4 km-long vacuum beam tubes are nearly finished. First articles of all scientific subsystems were tested, and no obstacles to the planned performance are anticipated. An experiment at MIT showed the ability to split an optical fringe to one part in ten billion. The group is moving to a new lab that enables next-generation LIGO research and development. (Prof. R. Weiss & Drs. D. Shoemaker, M. Zucker, P. Fritchel)
Theoretical investigations include: supercomputer simulations of large scale structure in the universe (Prof. E. Bertschinger) and of the hydrodynamics of binary star coalescence (Prof. F. Rasio); work on the origins and dynamical evolution of extrasolar planetary systems (Prof. F. Rasio); studies of the evolutionary histories of collapsed stars (white dwarfs, neutron stars, and black holes) in binary systems, including cataclysmic variables, low mass X-ray binaries, binary millisecond pulsars, and the effects of binary membership on supernovae (Profs. S. Rappaport & P. Joss). Theory of anomalous plasma viscosity first seen in the lab has been applied to the long-standing problem of angular momentum transport in accretion disks (Prof. B. Coppi). Closer to Earth, a new innovative theory of multiscale intermittent turbulence has been developed for the description of the Earth's magnetotail. (Dr. T. Chang).
In the area of aerospace technology, an Enhanced Dynamic Load Sensors Experiment has been conducted on the MIR space station by astronauts Shannon Lucid and Jerry Lingenger to assess the impact of human activity on the microgravity environment of space station (Prof. D. Newman). Flight simulator research continues on cockpit displays and virtual microgravity simulation (Drs. C. Oman and A. Beall). Dr. Oman's experiment on human visual orientation was successfully conducted on the STS-90 "neurolab" mission in April. MIT is one of seven institutions selected for NASA's new National Space Biomedical Research Institute; Prof. L. Young is the first NSBRI director.
Development is underway for a new High Energy Transient Experiment (HETE), to search for gamma ray burst sources, and launch options are being negotiated with NASA (Drs. G. Ricker, J. Doty, R. Vanderspeck, J. Crew). New X-ray CCD cameras are nearly complete for the next Japanese/U.S. mission, Astro-E, to be launched in 1999 (Drs. G. Ricker & M. Bautz). Periodic nano-structures have been fabricated for use as UV filters on the Magnetopause to Aurora Global Exploration (MENA) mission, due for launch in January 2000. They give an unprecedented million-fold rejection of UV while passing neutral particles which will image zones of auroral activity (Dr. Schattenburg).
AXAF is a major NASA mission of the "great observatory" series, scheduled for launch during the next year. Two of the four scientific instruments, the High-Energy Transmission Grating Spectrometer (Prof. C. Canizares, D. Dewey, K. Flanagan, M. Schattenburg) and the AXAF Charge-Coupled Device (CCD) Imaging Spectrometer (Drs. Ricker & M. Bautz, F. Baganoff), have now been successfully completed and delivered to NASA. Final spacecraft integration and testing is underway and the first set of AXAF observations are fully planned. CSR is also active in the AXAF Science Center, which will oversee the operation of AXAF during the mission (Prof. Canizares, Drs. D. Davis, D. Dewey, K. Flanagan, J. Houck, D. Huenemoerder, H. Marshall, D. Schultz and M. Wise).
The EDLS experiment flown on MIR was returned to Earth in April and an advanced version is being developed for space station (Prof. D. Newman). A follow-on to the neurolab experiment on human spacial orientation in real and virtual environments, EVA biomechanics and human factors is also in development for space station (Profs. L. Young and D. Newman, Dr. C. Oman).
Work on advanced X-ray optics, ultra-smooth reflection gratings and advanced X-ray CCD's continues. Potential applications include NASA's future Constellation X-ray mission. (Prof. Canizares, Drs. Ricker, Bautz, Schattenburg). Possible concepts are being developed for a mission in gamma ray burst detection (Drs. Ricker, Doty, Levine), and for a laser-ranged drag-free spacecraft to probe parameters in general relativity, solar flattening, and celestial mechanics (Prof. Zuber, Dr. W. Mayer, Mr. R. Goeke).
More information about this center can be found on the World Wide Web at the following URL: http://space.mit.edu
Claude R. Canizares
MIT Reports to the President 1997-98