High Energy Astrophysics Group

OSO-7

Orbiting Solar Observatory-7

The OSO-7 satellite was launched on September 29, 1971 into a 93 minute, 33 degree inclination orbit.

Due to a failure in the control system of the second stage of the Delta launcher during a final short injection burn, the initial orbit, with apogee of 575 km and perigee of 330 km, differed from the planned circular 550 km orbit. This severely affected the radiation environment encountered by OSO-7 and the proton-induced detector background. The satellite was controlled to keep the sun within 3 degrees of its equatorial plane for maximum solar power and to allow detailed studies to be made of the sun by the pointed instruments.

The mission went well for twenty months until the failure of the second spacecraft tape recorder on May, 18, 1973. The spacecraft reentered the earth's atmosphere and was destroyed in July of 1974.

--- Ph. D. Theses ---

W. A. Wheaton, 1976, UCSD, "Observation of the Galactic Hard X-Ray Background from the OSO-7 Satellite"

M. J. Elcan, 1979, UCSD, "The Solar Impulsive Hard X-Ray Spectrum"

OSO-7 Information

Mission Objectives
Spacecraft
Cosmic X--ray Experiment
Solar X--ray Experiment
Results
Publications