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Solar System Exploration
Asiasat 3/HGS-1
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Asiasat 3/HGS-1 Mission to Earth's Moon

Mission Type: Flyby, Orbiter
Launch Vehicle: 8K82K + Blok DM3 (Proton- K no. 394-01 / Blok DM3 no. 5L)
Launch Site: Baikonur Cosmodrome, USSR
Spacecraft Mass: 3,465 kg
Spacecraft Instruments: None
Spacecraft Dimensions: The body-stabilized satellite was 26.2 m tip-to-tip along the axis of the solar arrays and 10 m across the axis of the antennas. The bus was essentially a cube, roughly 4 m on a side.
Maximum Power: 9900.0 W
Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, Monographs in Aerospace History No. 24, by Asif A. Siddiqi

National Space Science Data Center,

Asiasat 3 was a communications satellite, launched by the Russians for Asia Satellite Telecommunications Company, that ended up in an incorrect orbit after a failure of the Blok DM3 upper stage.

Because of the improper second firing of the Blok DM3, the satellite ended up in a useless 203 x 36,000-kilometer orbit and was written off as a loss by Asiasat. Insurance underwriters subsequently signed an agreement with Hughes Global Systems (who also built the satellite) to salvage the vehicle and bring it to its originally intended geostationary orbit by using as little propellant as possible.

Using eleven carefully planned burns beginning 12 April 1998, controllers raised the orbit's apogee to 321,000 kilometers. Then, with the twelfth firing on 7 May 1998, the spacecraft was sent on a nine-day round trip around the Moon, approaching as close as 6,200 kilometers to its surface on 13 May. Using this gravity assist, Asiasat 3 hurtled back into a usable orbit. By 16 May 1998, perigee had been raised to 42,000 kilometers and inclination reduced from 51ý to 18ý.

A second circumlunar mission began on 1 June and culminated in a 34,300-kilometer flyby of the Moon. After four more engine firings, the satellite was finally in a 24-hour orbit by 17 June 1998. The satellite was renamed HGS 1 and was later sold and renamed PanAmSat 22.

Key Dates
24 Dec 1997:  Launch
Status: Success
Fast Facts
Asiasat Facts China's AsiaSat 3 was to provide television and telecommunication services for Asia, the Middle East and Australasia.

An investigation found the satellite exceeded the booster rocket's maximum payload.

This was the first use of the Moon's gravity to salvage a commercial satellite.
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Last Updated: 3 Jun 2013