Co-investigators Chien Wang , John Richardson , John Belcher
Project Website http://web.mit.edu/space/www/
Experimental and theoretical research in the astrophysics division also encompasses space and laboratory plasma physics. In situ measurements of space plasmas -- governed by the same laws as the confined plasmas now studied intensively in laboratories -- afford opportunities to study directly the behavior of plasmas under widely varying conditions. The MIT Space Plasma Group has developed plasma detectors for many Earth-orbiting (e.g., IMP-8) and deep-space probes. Results from these instruments have delineated the structure of the solar wind throughout the solar cycle, and have elucidated the complex interactions of the solar wind with the planets and with Halley's comet. MIT measurements internal to the six known magnetospheres in the solar system (Mercury, Earth, Jupiter, Saturn, Uranus, and Neptune) have provided a wealth of information about the plasmas in planetary magnetospheres, their sources, transport, and energization. Information about the distant solar wind is continually being returned by the MIT plasma detector on board Voyager 2, which is now well beyond the orbit of Pluto. In addition to continuing data analysis, the group is currently involved in developing instrumentation for the WIND spacecraft, a part of NASA's Global Geospace Science program.
In the area of the theory of space plasmas, MIT has the Center for Theoretical Geo/Cosmo Plasma Physics, sponsored primarily by NASA and the Air Force Office of Scientific Research. Currently, a substantial program exists in the study of weak and strong plasma turbulence, stochasticity and chaos, wave generation and propagation, plasma instabilities, and particle energization processes in the space environment. These studies apply the basic kinetic theory of charged particles in magnetized space environments to the various micro-, meso-, and macro-scale phenomena commonly observed in the solar wind, planetary magnetospheres and ionospheres, and other regimes.
The group has active instruments on three spacecraft, IMP 8 , Voyager 2 , and WIND. In each case these instruments are Faraday cup detectors which detect plasma with energies less than 10 keV. IMP 8, Voyager 2, and WIND all spend most of their time in the solar wind and detect solar wind plasma. This enables the group to study how the solar wind changes as it moves away from the Sun.