SCORE (satellite)
SCORE ( Signal Communications by Orbiting Relay Equipment, Project SCORE also ) was the first communications satellite. After starting with a modified Atlas B intercontinental ballistic missile on 18 December 1958, the U.S. Army conducted with SCORE transfer experiments. Sensation was caused by the emission of the SCORE recorded on a tape recorder of the satellite before the start of the Christmas message, U.S. President Dwight D. Eisenhower.
Construction
The SCORE satellite was in contrast to most other satellites not a separate, detachable missiles, but fully integrated into the launcher. The rocket itself was largely unchanged taken from the Atlas intercontinental ballistic missile testing program. Only re-entry has been replaced by a simple aerodynamic fairing.
The payload was (New Jersey) developed on behalf of ARPA of the military communications research engineer Kenneth Masterman -Smith in collaboration with a team from the United States Army Signal Research and Development Laboratory ( SRDL ) under the direction of Hans Ziegler at Fort Monmouth in just six months and built.
68 kg SCORE load consisted of two redundant systems, each of which consisted of a receiver, a transmitter and a miniature tape recorder. This communication device could be operated both in store- dump mode, in which first a sent message was recorded on tape and was later sent to a command from the ground station again, as well as in direct mode where the received message was simultaneously radiated from the transmitter again. In each case two adjacent to the missile body transmit and receive antennas were used for signal transmission.
As a power supply were silver - zinc batteries with an output of 56 watts, which should be sufficient for the expected 21-day lifespan of the satellite. The total mass of the SCORE satellite ( with Atlas rocket) was 3970 kg, making him the hitherto most severe artificial object in orbit.
Mission
The Atlas B missile with the serial number 10B was launched on 18 December 1958 by the Cape Canaveral Air Force Station launch pad LC - 11th During the ascent of the booster section was dropped two of three main engines. The remaining engine accelerated the rising Atlas rocket with the payload built on until the rocket into an orbit of 185 km x 1484 km with an inclination of 32.3 ° einschwenkte. The satellite launch had been prepared under complete secrecy and a large part of the staff involved was not informed that it was not the testing of an intercontinental ballistic missile but a satellite launch at the start. Christmas message from the President was recorded shortly before the start of the radio and replaced with another text.
When you first fly over the ground station, the primary communication device did not respond to commands from the ground station, but was a little later the secondary device to be activated. All tests were carried out communication with the secondary system.
On December 19, 1958 SCORE sent the first recording of a human voice from space. The speech of the U.S. President Dwight D. Eisenhower was:
In the following days both voice and telegraph messages were sent to the satellite, stored and sent later. In addition, some remotes were held. After twelve days in orbit the power failed on December 30, 1958. Until then about eight hours have been achieved in transmission time.
On January 21, 1959 SCORE burned up in Earth's atmosphere.