Upper Atmosphere Research Satellite

The Upper Atmosphere Research Satellite (UARS) is an orbital 14,500-pound U.S. observatory that made the most extensive study ever conducted of the Earth's troposphere, the upper level of the planet's envelope of life-sustaining gases which also include the protective ozone layer. UARS has ten sensing and measuring devices:

• Cryogenic Limb Array Etalon Spectrometer (CLAES)
• Improved Stratospheric and Mesospheric Sounder (ISAMS)
• Microwave Limb Sounder (MLS)
• Halogen Occultation Experiment (HALOE)
• High Resolution Doppler Imager (HRDI)
• Wind Imaging Interferometer (WINDII)
• Solar Ultraviolet Spectral Irradiance Monitor (SUSIM)
• Solar/Stellar Irradiance Comparison Experiment (SOLSTICE)
• Particle Environment Monitor (PEM)
• Active Cavity Radiometer Irradiance Monitor (ACRIM II).

UARS was deployed as the primary mission of STS-48, in September 1991.

See also

• UARS summary from NASA Earth Science: http://www.earth.nasa.gov/history/uars/uars.html
• UARS project science office page: http://umpgal.gsfc.nasa.gov/