Solar, Anomalous, and Magnetospheric Particle Explorer
Launch Date: July 03, 1992
SAMPEX is the first of NASA's Small Explorer (SMEX) missions. SAMPEX was designed to study the energy, composition and charge states of four classes of charged particles that originate beyond the Earth: (1) galactic cosmic rays (from supernova explosions in our Galaxy); (2) anomalous cosmic rays (from the interstellar gas surrounding our solar system); (3) solar energetic particles (from explosions in the solar atmosphere); and (4) magnetospheric electrons (particles from the solar wind trapped by the Earth's magnetic field). SAMPEX observations were able to provide important new information on the cosmic abundances of elements and their isotopes, the composition of local interstellar gas, the solar composition and the mechanisms responsible for solar atmospheric heating, and electron energy injection into the Earth's upper atmosphere.