NASA plans to launch a small satellite Monday to provide a team of researchers, led by a scientist at the University of Maryland, with its closest look yet at the squalls of cosmic rays constantly bombarding the Earth's magnetic field.
The Solar, Anomalous and Magnetospheric Particle Explorer, called SAMPEX, is scheduled for launch from Vandenberg Air Force Base near Lompoc, Calif., aboard a Scout rocket, in its yearlong mission.
"It is science of great impact, in a spacecraft you can wrap your arms around, at relatively low cost," said Orlando Figueroa, project manager for SAMPEX at Goddard Space Flight Center in Greenbelt, Md.
The $26.7 million satellite carries four instruments designed to detect and analyze fast-moving subatomic particles that are expected to provide clues about the relative abundance of various elements in the Sun, other stars in the Milky Way and the vast clouds of gas between the stars.
It will also measure the flow of electrons entering the atmosphere at near the speed of light. These particles may help destroy the Earth's protective layer of ozone in the upper atmosphere.
Glenn M. Mason, a professor of physics at the University of Maryland, will lead a team of 10 co-investigators on the project, which is expected to gather data from 10 to 100 times more galactic cosmic rays and energetic solar particles than any previous mission.
Scientists are particularly interested in analyzing "anomalous" cosmic rays, thought to be the shattered remnants of atoms of interstellar gas that are struck by the shock wave at the edge of the solar wind -- the fast-moving mist of particles generated by the sun that extends to the edge of the heliosphere, or the sun's magnetic field.
The collision apparently ionizes the gas atoms, stripping them of some or all of their electrons, and accelerates them to cosmic ray energies.
SAMPEX was developed by Goddard as part of an effort to
create small, relatively inexpensive scientific satellites. Data from the mission will be gathered at the University of Maryland's Science Operations Center.