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28 April 1989
Vol 244, Issue 4903

About The Cover

Artist's rendering of a Soviet Radar Ocean Reconnaissance Satellite, or RORSAT, which is used by the Soviet military to follow U.S. naval fleet movements. The electrons, positrons, and gamma rays produced by the RORSAT's nuclear power reactor have interfered with the efforts of astronomers to measure gamma-ray sources such as the sun and supernovae. The reactor core, shown being ejected, is designed to be boosted into a storage orbit at the end of the RORSAT's useful life. See Perspective, page 407, and Reports, page 441 to 451. [Artwork by Paul Roberts/Bill Burrows and Associates, based on information provided by Charles P. Vick]