Results of the Telstar Satellite Space Experiments

1475 I486 THE BELL SYSTEM TECHNICAL JOURNAL, JULY l'JG.'i magnetic moment of the satellite. This type of information is helpful in developing orientation schemes for future satellites. The spacecraft was designed and tested to withstand the environmental conditions it would see throughout launch and its life in orbit, based on the known and assumed aspects of its environment. By placing the spacecraft in orbit, the assumptions made could be evaluated. The most meaningful test of a communications satellite is the test of how well its electronics circuitry operates under actual space conditions. The results of the successful communications experiments are discussed in a separate paper in this issue. In this paper, the emphasis is placed on changes that may have occurred since launch on July 10, 1962. When the Telstar satellite was launched, it was injected in the predicted orbit with the spin axis favorably orientated with respect to the sun at a time of day which resulted in 14 full sunlit days before the satellite entered periods of eclipse. The initial orbit parameters were as follows: Apogee 3047 nautical miles Perigee 515 nautical miles Inclination 44.79 degrees Spin rate 177.7 rpm Solar aspect 90.5 degrees During the period from launch on July 10, 1962, to the time of interruption of the VHF command system on November 23, 1962, there were only minor variations in the power levels and the operating characteristics of the communications repeater in the satellite. The satellite temperature, attitude, visibility times, and eclipse times have varied as anticipated.