Draft:Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources

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Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources

Names	TERRIERS STEDI 2 Explorer 76
Mission type	Ionospheric physics
Operator	NASA
COSPAR ID	1999-026A
SATCAT no.	25735
Mission duration	1 year (planned) 8 hours (actual)
Spacecraft properties
Spacecraft	Explorer LXXVI
Spacecraft type	Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources
Bus	HETE
Launch mass	125 kg (276 lb)
Start of mission
Launch date	18 May 1999, 05:09:00 UTC
Rocket	Pegasus XL (F27)
Launch site	Vandenberg, Stargazer
Contractor	Orbital Sciences Corporation
End of mission
Deactivated	18 May 1999, 13:37 UTC[1]
Orbital parameters
Reference system	Geocentric orbit
Regime	Sun-synchronous orbit
Perigee altitude	493 km (306 mi)
Apogee altitude	484 km (301 mi)
Inclination	97.10°
Period	95.40 minutes
Instruments
Tomographic EUV Spectrographs (TESS) Gas Ionization Solar Spectral MOnitor (GISSMO)
STEDI Program ← Student Nitric Oxide Explorer (STEDI 1) Cooperative Astrophysics & Technology Satellite (STEDI 3) (cancelled) → Explorer program ← Wide Field Infrared Explorer (Explorer 75) Far Ultraviolet Spectroscopic Explorer (Explorer 77) →

Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources (TERRIERS, STEDI 2, or Explorer 76) was a NASA artificial satellite created by the STEDI program (Student Explorer Demonstration Initiative), intended to study Earth's ionospheric and thermospheric processes.^[2] It launched on 18 May 1999 from Vadenberg Space Force Base on a Pegasus rocket. The mission failed when the spacecraft was unable to orient its solar panel towards the Sun, and its batteries died 2 days after launch.^[3]

The goal of TERRIERS was to study the Earth's upper atmosphere, using tomography to create a model of the ionosphere, and to build a 3-dimensional map of the electron density in the upper atmosphere. This was to be accomplished using five extreme ultraviolet spectrometers. TERRIERS was also equipped with a Gas Ionization Solar Spectral Monitor (GISSMO) to track solar radiation.^[4]

The satellite was designed to spin at three revolutions per minute, using a photodiode and magnetic coils to control its spin rate and velocity. The body of the satellite was similar to High Energy Transient Explorer 1.

• Wade, Mark (2008). "TERRIERS". Archived from the original on 7 January 2010. Retrieved 29 June 2009.
• Darling, David (2009). "TERRIERS (Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources)". Retrieved 29 June 2009.

Category:Earth observation satellites Category:Spacecraft launched in 1999 Category:Satellites of the United States