Orbital built the Solar Radiation and Climate Experiment (SORCE) satellite for NASA under contract to the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder, Colorado. The SORCE program merges two previous efforts: the Solar-Stellar Irradiance Comparison Experiment/Solar Atmospheric Variability Explorer (SOLSTICE/SAVE) mission and the Total Solar Irradiance Mission (TSIM).
The SORCE satellite carries four instruments to study and measure solar irradiance, the main source of energy in the Earth's atmosphere. The spacecraft was launched aboard Orbital's Pegasus rocket on January 25, 2003 on a mission that originated from Cape Canaveral, Florida. On March 6, 2003 the instruments on board the satellite began making daily solar observations.
Orbit: 645 km circular @ 40°
Launch Mass: 288 kg
Solar Arrays: 795 W EOL, fixed deployable solar arrays
Stabilization: 3-axis, zero momentum
Mission life: 5 years, 6 year goal
Operational. The mission has completed its planned 5 years and has been approved for extended mission operations. The bus has performed nominally on orbit since launch and has never had an anomaly resulting in use of the redundant "B side" components.
Customer: University of Colorado at Boulder, Laboratory for Atmospheric & Space
Mission: NASA Earth Observing System (EOS) program
Merger of previous SOLSTICE/SAVE and TSIM
Solar irradiance studies