Center for Space Research
The Center for Space Research (CSR) conducts research in astronomy, astrophysics, space science, detector engineering, and related technology, and participates in various National Aeronautical and Space Administration (NASA) flight missions. Specific areas of research include extragalactic astronomy and cosmology, galactic astronomy, the solar system and space plasma physics, and the space life sciences. Research conducted in CSR is reported by the departments of Physics, Earth Atmospheric and Planetary Sciences, Aeronautics and Astronautics, and Chemical Engineering, and by the Harvard-MIT Division of Health Sciences and Technology.
CSR supports MIT involvement in three major observatories: the Magellan Observatory (Professor Schechter, MIT Director), the Laser Interferometric Gravitational-wave Observatory (LIGO; Dr. Shoemaker, MIT Director), and the Chandra X-Ray Observatory (CXO; Professor Canizares, Associate Director). The Magellan consortium is building two 6.5-meter diameter optical telescopes in Chile. The first of these began routine science operations in February 2001. The second saw first light in June 2002 and will begin science operations in September 2002. The LIGO Laboratory, a collaboration of Caltech and MIT, is engaged in developing and commissioning gravitational wave telescopes. The initial LIGO detectors in Washington and Louisiana have come into operation in the past year. R&D continues on next generation instrumentation for Advanced LIGO, expected to operate at the end of this decade, and for future detectors. The Chandra satellite was launched as a major NASA mission in 1999 and continues to be extremely productive. Two of the four Chandra scientific instruments were built at CSR, the High-Energy Transmission Grating Spectrometer and ACIS, a Charge-Coupled Device (CCD) imaging spectrometer. CSR is also active in the Chandra X-Ray Observatory Science Center (CXC).
In addition to the major observatories, CSR is involved in several more focused space missions. The Rossi X-ray Timing Explorer (RXTE; Dr. Levine, PI) has entered its seventh year of successful operation. CSR's All-Sky Monitor instrument continuously surveys the sky for new sources and guides the activities of other observatories. The HETE-2 mission (Dr. Ricker, PI), built and operated at MIT with US and international collaborators, was launched in 2000 and is dedicated to the detection and prompt localization of the sources of gamma-ray bursts. Construction of detectors for ASTRO-E2 (Dr. Bautz, PI), a reflight of the failed ASTRO-E X-ray spectroscopy mission, is under way. The SPIDR mission was recently selected by NASA as a new SMEX mission. Led by Boston University, with significant contribution from MIT and other institutions, this mission will probe the hot intergalactic ionized gas, believed to be the repository of most of the baryons in the present-day universe.
CSR's Space Nanotechnology Laboratory, directed by Dr. Schattenburg, seeks to apply micro and nanofabrication technology to achieve dramatic improvements in lightweight high-resolution optical components including foil-optic mirrors and diffraction gratings.
CSR is the new home of the astrophysics division of the physics department. Recent renovations have made possible the co-location of nearly all faculty to a common area, bringing together faculty, research staff, postdocs, and students. Students actively participate in research projects; in the past year 32 graduate students and 29 undergraduate students were supported by CSR.
Extragalactic Astronomy and Cosmology
(Professors Bertschinger, Bradt, Burles, Canizares, Morrison, Schechter; Doctors Arabadjis, Bautz, Crew, Doty, Fang, Ford, Gu, Houck, Lee, Machacek, Marshall, Ricker, Vanderspek, Villasenor, Wise)
Four new gravitational lenses have been discovered with the Magellan telescope. Several of these exhibit flux ratio anomalies which may be evidence for smoothly distributed nonbaryonic dark matter in galaxies. The dynamics of the largest structures in the universe are being investigated with ACIS in studies of cluster merging and cooling and in studies of the kiloparsec-scale jets in active galactic nuclei. A major result from HETG was the first detection of an X-ray absorption line from a modest over-density in the warm-hot intergalactic medium along the line of sight to a distant AGN. In theoretical studies, a new computational approach for the interpretation of cosmic microwave background anisotropies has been developed, and a code for preparing multiscale initial conditions for cosmological simulations has been written and provided to the community.
An important development in the field of GRB studies was the first localization by HETE-2 of a "short-hard" GRB, a type of burst possibly different from the "long" GRB's that have been studied in the past. Vigorous follow-up work with Chandra, Magellan, and other observatories is under way.
(Professors Bertschinger, Canizares, Chakrabarty, Joss, Lewin, and Rappaport; Doctors Allen, Baganoff, Dewey, Flanagan, Galloway, Huenemoerder, Ishibashi, Jiminez, Lee, Marshall, Morgan, Pannuti, Remillard, Schulz, Wodjowski)
An unprecedented week-long campaign of observations of the galactic center was carried out using most of the world's largest observatories at all wavelengths. New X-ray flares from the black hole were discovered and broadband spectra of the system were measured. In further studies that probe near the event horizons of black holes, data from the Chandra, RXTE, and XMM observatories show evidence for black hole spin, greatly strengthening the case for the existence of the so-called Kerr black holes. Fast quasiperiodic oscillations from black holes detected by RXTE provide evidence for resonances closely related to relativistic effects and are being compared to fully general relativistic models of hotspots orbiting black holes. RXTE data have also led to the discovery of the third millisecond X-ray pulsar.
High resolution spectra obtained with HETG have been used to probe the relativistic outflow from galactic microquasars and to study spectral features in X-ray binaries, plasma accretion processes, atmospheres of neutron stars, stellar coronae and winds, supernovae, and young supernova remnants. The properties of supernova remnants and their cosmic ray spectra have been further elucidated by combined radio, X-ray and optical observations. This wealth of new data is being interpreted in light of theoretical modeling. Population synthesis studies of binary star systems containing white dwarfs, neutron stars, and black holes are being carried out in an effort to model cataclysmic variables, low-mass X-ray binaries, binary radio pulsars, and black hole binaries. Detailed new neutron star atmosphere models are being developed, incorporating general relativistic effects and Compton scattering.
The Solar System and Space Plasma Physics
(Professors Pettengill and Belcher; Doctors Ashmall, Chang, Clack, Ford, Jurac, Lazarus, Richardson, Wang)
In recent years, Mars has been the subject of intensive study by a number of instruments. Data from the Laser Altimeter Instrument (MOLA) and the Thermal Emission Spectrometer (TES), both aboard the Mars Global Surveyor, have been used to investigate the atmospheric conditions under which carbon dioxide clouds form and precipitate in the Martial polar night.
Studies of plasma in the solar wind continue from three spacecraft: IMP 8 and Wind, near Earth, and Voyager 2, currently at 65 AU. These studies have demonstrated for the first time the presence of marginal instability limits associated with plasma wave modes, provided an estimate of the density of interstellar hydrogen, and shown a source of OH at Saturn near Enceladus. A high-time-resolution solar wind experiment on the Triana spacecraft is expected to be launched within two years. An innovative theory of complexity in space plasmas in the Earth's magnetosphere and the solar corona has been developed using the concepts of forced and/or self-organized criticality and topological phase transitions.
Human Space Flight
(Professor Young; Doctors Hecht, Oman, Kundakovic, Mast, Natapoff, Vunjak-Novakovic)
CSR has initiated the design of virtual reality display devices, restraint systems, and software tools for the International Space Station Human Research Facility. The system supports VOILA (Visuomotor and Orientation Investigations in Long Duration Astronauts), a set of flight experiments planned for 2002-2005. The artificial gravity team has made significant progress toward testing short radius centrifugation with the goal of reducing its unpleasant side effects and putting this more affordable technology within reach as a countermeasure against space deconditioning. Another CSR team is developing the Cell Culture Unit for biological experiments on the Space Station.
Instrumentation for the Future
(Professors Hewitt, Schechter; Doctors Bautz, Levine, Ricker, Schattenburg)
Looking toward future missions, new technology is being developed for advanced X-ray CCD sensors in collaboration with MIT's Lincoln Laboratory. GEM detectors are being adapted for use in space in collaboration with MIT's Laboratory for Nuclear Science. Work continues in the Space Nanotechnology Laboratory on advanced X-ray optics with applications targeted to future missions such as Constellation X and MicroArcsecond X-ray Imaging Mission. An adaptive optics system for Magellan is under development. With colleagues at Haystack Observatory work continues on the development of a large low-frequency array, which will also serve as a prototype for the future Square Kilometer Array.
More information about the Center for Space Research can be found on the web at http://space.mit.edu/.