TOMS

Total Ozone Mapping Satellite

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General

Designation	23940 / 96037A
Launch date	2 Jul 1996
Country of origin	United States
Mission	Remote sensing
Perigee/Apogee	500 km (sunsynchronous)
Inclination	97.4°
Period	96.7 min
Launch vehicle	Pegasus XL #12

TOMS will focus on tropospheric ozone, to monitor its depletion. It measures total ozone by observing both incoming solar energy and backscattered ultraviolet radiation at six wavelengths. Backscattered radiation is solar radiation that has penetrated the Earth's lower atmosphere and been reflected by air molecules and clouds back through the stratosphere to the satellite sensors.

In Dec 1998 the satellite was hit by a high-energy particle which disrupted the on-board computer and the satellite ended in safe mode. There was a problem with this mode and the stabilization processed exhumed the fuel. TRW came up with a solution to regain control over the satellite by using its magnetic torque. This was successful and the satellite uses this stabilization method since Jan 1999.

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External resources

http://pao.gsfc.nasa.gov/gsfc/service/gallery/fact_sheets/earthsci/toms.htm

http://jwocky.gsfc.nasa.gov/
sat-index articles

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End of life

Out of service	Dec 2006
Cause	Transmitter failure
Decay

Technical data

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Specifications

Prime contractor	TRW
Platform	STEP/Eagle
Mass at launch	261 kg
Mass in orbit	215 kg
Dimension	2.4 x 3.9 m
Solar array
Stabilization	3 axis
DC power	128 W
Design lifetime	2 years

Single instrument: TOMS which already flew on Nimbus 7 (1978) and Meteor 3-05 (1991). It should also fly on Adeos 1

Telemetry: 2273.50 MHz (3 downlink rates: 1.1 kbps, 50 kbps, 200 kbps)
Command: 2093.51 MHz

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