The University of Colorado at Boulder has been selected to design, build, operate and control a NASA satellite that will study the response of Earth's Van Allen radiation belts to the powerful solar wind.
The $12.8 million satellite project, known as the Inner Magnetosphere Explorer, or IMEX, is being directed by Professor John Wygant of the University of Minnesota in Minneapolis. Co-Investigators include Daniel Baker, director of CU-Boulder's Laboratory for Atmospheric and Space Physics, and LASP Associate Researcher Xinlin Li. CU-Boulder is expected to receive about half of the funding for the project.
The satellite fabrication, testing and operations role of CU-Boulder comes on the heels of the highly successful Student Nitric Oxide Explorer Mission, a $4.1 million project managed by the Universities Space Research Association for NASA. Designed, built and launched by LASP in February, the satellite is now under control of CU students and faculty on campus.
IMEX will study the energetic charged particles -- primarily protons and electrons -- that comprise Earth's radiation zones. "These zones are potentially hazardous to both astronauts and satellite systems," said Li.
In 1996, Baker's research indicated the operational failure of a Canadian communications satellite appeared to be linked to severe space weather.
Evidence showed the activity of high-energy electrons in Earth's outer magnetosphere rose in intensity two weeks prior to failure of the Anik E1 spacecraft, causing it to lose power in a solar panel array, permanently degrading its communication ability and temporarily interrupting video, voice and data service for Telesat Canada.
The Van Allen belts were discovered in 1958 by James Van Allen, a distinguished American physicist who identified two main regions in Earth's magnetosphere that contained intense concentrations of charged particles.
One zone is located about 12,000 miles above Earth, the other about 40,000 miles from Earth. The charged particles in the radiation belts are captured primarily by the solar wind and forced into lines by Earth's magnetic field, Baker said.
IMEX will be launched into an elliptical orbit around Earth ranging from 218 miles from the planet to nearly 22,000 miles from Earth with instruments to measure the populations of energetic particles and related magnetic and electric fields throughout Earth's radiation belts.
"This selection is another step in NASA's efforts to provide increased autonomy and responsibility to the university community in pursuit of new scientific knowledge," said Wesley Huntress, associate administrator for NASA's Office of Space Science in Washington, D.C.
"Data obtained with IMEX during its 10-hour orbital sweeps through the Van Allen Belts should lead to significant improvements in our ability to predict hazardous conditions in Earth's environment," said Baker. "It also should help in understanding the underlying physical processes that connect the solar wind with the behavior of the Van Allen Belts, especially during the upcoming maximum solar cycle."
The IMEX spacecraft was one of two space satellites selected by NASA as part of the agency's University-Class Explorer program. IMEX is slated for launch aboard an Air Force Titan IV rocket in June 2001, Baker said.
The second mission selected as part of NASA's University Class Explorer program is the Cosmic Hot Interstellar Plasma Spectrometer, known as CHIPS. Led by the University of California, Berkley scientist Mark Hurwitz, CHIPS will use an extreme ultraviolet spectrograph to study a tenuous cloud of hot gas surrounding the solar system known as the "Local Bubble."
The University Class Explorer Program was designed to provide frequent flight opportunities for focused and relatively inexpensive science missions under $13 million in cost. The program is managed by Goddard Space Flight Center in Greenbelt, Md., for NASA's Office of Space Science.