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TDRS-7

TDRS-G before launch at Kennedy Space Center
Mission type	Communication
Operator	NASA
COSPAR ID	1995-035B
SATCAT no.	23613
Mission duration	Planned: 10 years Elapsed: 29 years, 5 months and 19 days
Spacecraft properties
Bus	TDRS
Manufacturer	TRW
Launch mass	2,108 kilograms (4,647 lb)
Dimensions	17.3 metres (57 ft) long 14.2 metres (47 ft) wide
Power	1700 watts
Start of mission
Launch date	13 July 1995, 13:41:55 (1995-07-13UTC13:41:55) UTC
Rocket	Space Shuttle Discovery STS-70 / IUS
Launch site	Kennedy Space Center, LC-39B
Contractor	Rockwell International
Orbital parameters
Reference system	Geocentric orbit
Regime	Geostationary orbit
Longitude	150.0° West (1995–1996) 171.0° West (1996–2003) 150.5° West (2003–)
Epoch	14 July 1995

TDRS-7, known before launch as TDRS-G, 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 as a replacement for TDRS-B, which had been lost in the Challenger accident, and was the last first generation TDRS satellite to be launched.

History

TDRS-7 is based on a custom satellite bus which was used for all seven first generation TDRS satellites. Whilst similar to its predecessors, it differed from them slightly in that twelve G/H band (C band (IEEE)) transponders which had been included on the previous satellites were omitted. It was the last communications satellite, other than amateur radio spacecraft, to be deployed by a Space Shuttle.

Launch

The TDRS-G satellite was deployed from Space Shuttle Discovery during the STS-70 mission in 1995. Discovery was launched from Kennedy Space Center Launch Complex 39B at 13:41:55 UTC on 13 July 1995. TDRS-G was deployed from Discovery around six hours after launch, and was raised to geosynchronous orbit by means of an Inertial Upper Stage.

Deployment

The twin-stage solid-propellent Inertial Upper Stage made two burns. The first stage burn occurred around an hour after deployment from Discovery, and placed the satellite into a geosynchronous transfer orbit. At 02:30 UTC on 14 July 1995 it reached apogee, and the second stage fired, placing TDRS-G into geostationary orbit. At this point, it received its operational designation, TDRS-7. It was placed at a longitude 150.0° West of the Greenwich Meridian, where it underwent on-orbit testing. In May 1996, it was moved to 171.0° West where it was stored as an in-orbit spare, and subsequently entered service. In December 2003, it was relocated to 150.5° West. It arrived the next month, and was returned to storage as a reserve satellite.

See also

• List of TDRS satellites

References

1. "UCS Satellite Database". Union of Concerned Scientists. 1 July 2009. Retrieved 9 August 2009.
2. "NASA – NSSDCA – Spacecraft – Trajectory Details". nssdc.gsfc.nasa.gov. Retrieved 2 May 2018. This article incorporates text from this source, which is in the public domain.
3. Krebs, Gunter. "TDRS 1, 2, 3, 4, 5, 6". Gunter's Space Page. Retrieved 9 August 2009.
4. Krebs, Gunter. "TDRS 7". Gunter's Space Page. Retrieved 9 August 2009.
5. ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 9 August 2009.
6. McDowell, Jonathan. "Index". Geostationary Orbit Catalog. Jonathan's Space Page. Archived from the original on 6 April 2010. Retrieved 9 August 2009.
7. "The TDRS-J satellite". Spaceflight Now. 1 December 2002. Retrieved 9 August 2009.
8. "TDRS 7". TSE. Retrieved 9 August 2009.

v t e Tracking and Data Relay Satellite System
Tracking and data relay satellite List of TDRS satellites
First generation	TDRS-1 TDRS-B TDRS-3 TDRS-4 TDRS-5 TDRS-6 TDRS-7
Second generation	TDRS-8 TDRS-9 TDRS-10
Third generation	TDRS-11 TDRS-12 TDRS-13
Italics denotes launch failure.

• Communications satellites in geostationary orbit
• Spacecraft launched in 1995
• TDRS satellites
• Spacecraft launched by the Space Shuttle