 TDRS-C aboard Discovery | |
| Mission type | Communication |
|---|---|
| Operator | NASA |
| COSPAR ID | 1988-091B |
| SATCAT no. | 19548 [1] |
| Mission duration | Planned: 10 years Elapsed: 35 years, 3 months, 29 days |
| Spacecraft properties | |
| Bus | TDRS |
| Manufacturer | TRW |
| Launch mass | 2,224.9 kg (4,905 lb)[2] |
| Dimensions | 17.3 × 14.2 m (57 × 47 ft)[2] |
| Power | 1700 watts[2] |
| Start of mission | |
| Launch date | 29 September 1988, 15:37:00 UTC |
| Rocket | Space Shuttle Discovery STS-26 / IUS |
| Launch site | Kennedy Space Center LC-39B |
| Contractor | Rockwell International |
| Orbital parameters | |
| Reference system | Geocentric orbit |
| Regime | Geostationary orbit |
| Longitude | 151° West (1988) 171° West (1988–1990) 174° West (1990–1991) 62° West (1991–1994) 171° West (1994–1995) 85° East (1995–2009) 49° West (2009–) |
| Epoch | 29 September 1988 [3] |
TDRS-3, known before launch as TDRS-C, is an American communications satellite, of first generation, which is operated by NASA as part of the Tracking and Data Relay Satellite System. It was constructed by TRW, and is based on a custom satellite bus which was used for all seven first generation TDRS satellites.[4]
The TDRS-C satellite was launched aboard Space Shuttle Discovery during the STS-26 mission in 1988; the first Shuttle flight since the Challenger disaster which had resulted in the loss of the previous TDRS satellite, TDRS-B. Discovery launched from Launch Complex 39B at the Kennedy Space Center at 15:37:00 UTC on 29 September 1988.[5] TDRS-C was deployed from Discovery around six hours after launch, and was raised to geostationary orbit by means of an Inertial Upper Stage.[5]
The two-stage solid-propellent Inertial Upper Stage made two burns. The first stage burn occurred shortly after deployment from Discovery, and placed the satellite into a geosynchronous transfer orbit. At 04:30 UTC on 30 September 1988, it reached apogee, and the second stage fired, placing TDRS-C into geosynchronous orbit. At this point it received its operational designation. Although the TDRS-2 designation had not been assigned, TDRS-C was given the designation TDRS-3 as NASA did not want to reuse the designation which had been intended for the STS-51-L payload.[6] It was briefly placed at a longitude 151° West of the Greenwich Meridian, before being moved to 171.0° West before the end of 1988, from where it provided communications services to spacecraft in Earth orbit, including Space Shuttles. In 1990, it was relocated to 174.0° West, and again in 1991 to 62.0° West. In 1994, it returned to 171.0° West.[7][8] In June 1995, it was moved to 85.0° East, from where it was used primarily for communications with spacecraft such as the Compton Gamma Ray Observatory and the Hubble Space Telescope.[7][9] In October 2009, as NASA began decommissioning TDRS-1, TDRS-3 was moved to 49.0° West,[10] where it remains in storage as of 2020.[11]
