SCORE (Signal Communication by Orbiting Relay Equipment)
The world's first communications satellite was Project SCORE (Signal Communication by Orbiting Relay Equipment), launched from Cape Canaveral using an Atlas B missile on Dec. 18, 1958. Among other firsts, it was the first successful trial of the Atlas as a space launch vehicle. At this early stage of the world's space programs - Sputniks 1 and 2 had been launched only a little over a year earlier, on Oct. 4 and Nov. 3, 1957 - the primary objective of the mission was simply to place the body of the missile into low earth orbit, and AFBMD's primary role was to provide the missile and the launch. The communications package was built from modified commercial equipment by the Army Signal Research and Development Laboratory under the direction of the Advanced Research Projects Agency.
In late June 1958, the U.S. Army Signal Research and Development Laboratory (SRDL) at Fort Monmouth, New Jersey was directed to construct a communications satellite with a maximum weight of 150 pounds. The launch vehicle would be an Air Force Atlas ICBM. The entire rocket was to be placed into orbit and, therefore, it was decided that the communications equipment would be integrated into the fairing pods of the missile. The orbit was expected to be low, therefore life expectancy of the satellite was only 2 to 3 weeks. The low orbit and short life would limit opportunities for realtime relay between two ground stations, therefore, a storeandforward mode was added by including a tape recorder. This would also give the satellite a worldwide broadcast capability. Since reliability was a concern, a second tape recorder was added to the communications package. The work progressed in strict secrecy.
By December 1958, the Army's SCORE (Signal Communications by Orbiting Relay Equipment) satellite was ready to be launched. A prerecorded message prepared by a member of the SRDLSCORE team was loaded in the tape recorders. At the last minute, however, President Eisenhower was persuaded to record a Christmas message to the world. The President's tape was rushed to the Cape Canaveral launch site. The communications package was already sealed in the Atlas missile which was on the launch pad and fueled. On the morning of 18 December, the Signal Corps transmitted the President's message across Cape Canaveral to the communications payload on the waiting rocket. The SCORE payload dutifully recorded the new message onto both the primary and backup tape recorders.
At 1802 hours, 18 December 1958 the Atlas missile was launched into an orbit with a perigee of 114 miles, an apogee of 920 miles, an inclination of 32.3 degrees and a period of 101.5 minutes. On the first orbit, as the satellite passed over California, the primary payload did not respond properly. Finally on 19 December, the backup tape recorder responded to coded commands from the ground and transmitted the President's message on a short-wave frequency to the world below.
"This is the President of the United States speaking. Through the marvels of scientific advance, my voice is coming to you from a satellite traveling in outer space. My message is a simple one: Through this unique means I convey to you and all mankind, America's wish for peace on Earth and goodwill toward men everywhere."
The second SCORE package continued to work perfectly, responding to 78 realtime and storeandforward voice and teletype transmissions between ground stations located in Georgia, Texas, Arizona and California. After 12 days the batteries failed. On 21 January 1959, the satellite reentered the Earth's atmosphere and burned up.
Air Force Atlas
The Air Force's 9,000 pound Atlas rocket body was the heaviest object to have been launched into orbit and the Army's SCORE satellite was the first communications satellite. The broader military significance of the experiment was it demonstrated the practical operation of a satellite radio-relay system with intercontinental capability.
Sources and Resources
- Chapter 2 ARMY SPACE HISTORY
- Celebrating Our Past: The first communications satellite -- Harry Waldron -History Office
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