Primary Processor and Data Storage Equipment for the Orbiting Astronomical Observatory

Telescopes in space will soon permit astronomers to observe the heavens in more detail than ever before. The Orbiting Astronomical Observatory (OAO) is a space vehicle designed to place these telescopes in orbit beyond the earth's atmosphere and to telemeter the collected data back to earth. To aid the orbiting observatory in the fulfillment of its scientific mission, a low-power, long-life, high-density command and memory system has been designed and is currently undergoing qualification testing. The digital command storage and processing element will permit reprogramming of spacecraft orientation and astronomical experiments on each orbit, even when the satellite is not in contact with the ground, while the core memory element will permit storage of experiment data for subsequent transmission to the ground. In the following paper, the functional design of the satellite command and memory system is discussed in detail. In addition, the power conservation methods, reliability design techniques and environmental performance considerations which influenced the design of this equipment are reviewed.