|
HomePage |
|
|
|
|
Research at MIT
Founded in 1965 with NASA support, MIT's Center for Space Research (CSR) is an interdepartmental center that conducts research in space science and engineering and in astronomy and astrophysics. Faculty and students from the Departments of Physics, Aeronautics and Astronautics, Mechanical Engineering, and EAPS are resident in CSR and work closely with CSR's research staff. We have offices and laboratories in three locations on campus: Building 37, Building NE80, and Buildings NW17 \NW22. CSR also supports MIT's participation in the Magellan Consortium, a consortium that operates two 6.5-meter optical telescopes on a mountaintop in Chile.
CSR's flagship project is our participation in the Chandra X-ray Observatory, a "Great Observatory" launched by NASA in July 1999. With its unprecedented combination of spatial and spectral resolution, Chandra is revolutionizing X-ray astronomy. For the first time, we have X-ray images with resolution comparable to that of optical images. CCD cameras on board the spacecraft produce the X-ray images. Inserting a transmission grating into the optical path allows the cameras to record X-ray spectra of astrophysical objects rather than images. Of the four instruments on Chandra, two (one CCD camera and one transmission grating) were built by CSR scientists and engineers. The precision construction techniques required for X-ray diffraction gratings were developed at CSR's Space Nanotechnology Laboratory.
Astrophysical X-ray sources are laboratories for high-energy phenomena such as supernovae, the accretion disks and jets associated with neutron stars and black holes, and high-energy particles that fill galaxy clusters. As an example, the figure shows a Chandra image of the center of our Galaxy. The bright emission at the center of the image is believed to be due to a black hole with a mass over a million times that of the sun. The evidence for the existence of this black hole is found in optical measurements of the orbits of stars around the black hole and in Chandra's measurements of rapid flaring activity. These Chandra studies also resulted in the serendipitous discovery of over 2000 new bright X-ray sources in the Galactic Center region. The new sources are believed to be primarily hot white dwarfs and neutron stars in our Galaxy.
We are involved in several other X-ray missions in addition to Chandra. The small explorer satellite, HETE-2, was designed and built at CSR, and is now operated from a laboratory in Building 37. HETE-2 carries wide-field X-ray and gamma-ray detectors designed to identify and localize gamma-ray bursts, extremely intense rapid bursts of gamma rays that are believed to originate in the collapse of massive stars. Another wide-field instrument, the All Sky Monitor on the Rossi X-ray Timing Explorer, was also designed and built at CSR. Still in operation since its 1995 launch, the ASM continuously surveys the sky, monitoring known bright X-ray sources and identifying new transient sources for further study.
Looking to the future, CSR scientists, engineers, and students are part of a worldwide collaboration that has its goal to develop a new type of astronomy, gravitational wave astronomy. Einstein's General Theory of Relativity predicts that accelerated masses should produce gravitational waves, in a way somewhat analogous to the production of electromagnetic waves by accelerated charges. There is indirect evidence for the existence of gravitational waves that comes from the observation of the loss of energy in an orbiting system consisting of a neutron star and a pulsar. Gravitational waves are much more difficult to detect than electromagnetic waves, however. If theoretical expectations about source strengths are correct, detecting gravitational waves requires building an instrument that can detect a change in distance between two objects of less than 10(-18) meters! MIT is collaborating with Caltech on the construction of two large laser interferometers, one in Washington state and one in Louisiana, that are designed to detect such small changes in distance. This Laser Interferometry Gravitational Wave Observatory has begun operation, and r&d for a planned upgrade is in progress.
In addition to the X-ray and gravitational wave projects described above, we have active programs in ground-based optical and radio astronomy, human adaptation to space flight, space engineering, space plasma physics, and planetary science. To learn more, I invite you to visit our Website, http://space.mit.edu or to take one of the tours we will be offering during IAP.
|
HomePage |
|
|
|
|