NASA Headquarters, Washington, DC
September 11, 1998


Small spacecraft to study the vast region between our Sun and nearby stars and the interaction of Earth's radiation belts with the solar wind have been selected as the first missions in NASA's University-class Explorers (UNEX) program.

"This selection is another step in NASA's efforts to provide increased autonomy and responsibility to the university community in the pursuit of new scientific knowledge," said Dr. Wesley T. Huntress Jr., Associate Administrator for NASA's Office of Space Science.

The Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) spacecraft will use an extreme ultraviolet spectrograph during its one-year mission to study the "Local Bubble," a tenuous cloud of hot gas surrounding our Solar System that extends about 300 light- years from the Sun. Scientists believe that the million-degree gas in this region is generated by supernovae and stellar winds from hot stars, but want to better understand the origins and cooling of this gas, and apply knowledge of these processes to the study of other galaxies beyond our Milky Way.

The Principal Investigator for CHIPS is Dr. Mark Hurwitz of the University of California, Berkeley. The Earth-orbiting mission will cost $9.8 million, including launch, and will be launched aboard a commercial Final Analysis Inc. Satellite (FAISAT) as a secondary payload on a Russian Cosmos rocket in mid- 2001.

The second mission, the Inner Magnetosphere Explorer (IMEX), will study the response of Earth's Van Allen radiation belts to variations in the solar wind. The energetic charged particles (mainly protons and electrons) that comprise Earth's radiation belts are potentially hazardous to both astronauts and satellite systems. IMEX will be launched into a 217-mile by 21,748-mile (350-kilometer by 35,000-kilometer) elliptical orbit around Earth with instruments to measure the populations of energetic particles and related magnetic and electric fields throughout Earth's radiation belts on a regular basis.

Together with other NASA satellites, data obtained with IMEX during these 10-hour sweeps should lead to significant improvements in our ability to predict hazardous conditions in Earth's radiation belts and our understanding of the underlying physical processes that connect the solar wind with the state of the Van Allen belts, especially during the upcoming maximum in the solar cycle. The Principal Investigator for IMEX is Dr. John Wygant of the University of Minnesota in Minneapolis. IMEX will cost $13 million and is planned to be launched as a secondary mission on an Air Force Titan IV rocket in June 2001.

The UNEX Program is designed to provide frequent flight opportunities for highly focused and relatively inexpensive science missions whose total cost to NASA is limited to $13 million. The program is managed by NASA's Goddard Space Flight Center, Greenbelt, MD, for the Office of Space Science, Washington, DC.

Back to ASTRONET's home page
Terug naar ASTRONET's home page