![]() Transition Region and Coronal Explorer satellite | |
Names | Explorer-73 SMEX-4 TRACE |
---|---|
Mission type | Heliophysics |
Operator | NASA / GSFC |
COSPAR ID | 1998-020A |
SATCAT no. | 25280 |
Website | TRACE |
Mission duration | 1 year (planned) 12 years, 2 months and 19 days (achieved) [1] |
Spacecraft properties | |
Spacecraft | Explorer LXXIII |
Spacecraft type | Transition Region and Coronal Explorer |
Bus | TRACE |
Manufacturer | Goddard Space Flight Center |
Launch mass | 250 kg (550 lb) |
Dimensions | 1.9 × 1.1 m (6 ft 3 in × 3 ft 7 in) |
Power | 220 watts |
Start of mission | |
Launch date | 2 April 1998, 02:42:39 UTC |
Rocket | Pegasus XL (F21) |
Launch site | Vandenberg, Stargazer |
Contractor | Orbital Sciences Corporation |
Entered service | 20 April 1998 |
End of mission | |
Deactivated | 21 June 2010, 23:56 UTC |
Last contact | 21 June 2010 |
Orbital parameters | |
Reference system | Geocentric orbit[2] |
Regime | Sun-synchronous orbit |
Perigee altitude | 520.0 km (323.1 mi) |
Apogee altitude | 547.2 km (340.0 mi) |
Inclination | 97.84° |
Period | 95.48 minutes |
Instruments | |
TRACE Imaging Telescope | |
![]() TRACE mission patch |
Transition Region and Coronal Explorer (TRACE, or Explorer 73, SMEX-4) was a NASA heliophysics and solar observatory designed to investigate the connections between fine-scale magnetic fields and the associated plasma structures on the Sun by providing high-resolution images and observation of the solar photosphere, the transition region, and the solar corona. A main focus of the TRACE instrument is the fine structure of coronal loops low in the solar atmosphere. TRACE is the third spacecraft in the Small Explorer program, launched on 2 April 1998, and obtained its last science image on 21 June 2010, at 23:56 UTC.[3]