Upper Atmosphere Research Satellite between positions downrange, generally northeast of this position. Upper Atmosphere Research Satellite The Upper Atmosphere Research Satellite (UARS) was a NASA-operated orbital observatory whose mission was to study the Earth’s atmosphere, particularly the protective ozone layer. The satellite was deployed from Space Shuttle "Discovery" during the STS-48 mission on 15 September 1991. It entered Earth orbit at an operational altitude of , with an orbital inclination of 57 degrees. The original mission duration was to be only three years, but was extended several times. When the mission finally ended in June 2005 due to funding cuts, 14 years after the
Ocean planet the HZ and the magnitude of their greenhouse effect. Several other surface and interior processes affect the atmospheric composition, including but not limited to the ocean fraction for dissolution of and for atmospheric relative humidity, redox state of the planetary surface and interior, acidity levels of the oceans, planetary albedo, and surface gravity. The atmospheric structure, as well as the resulting HZ limits, depend on the density of a planet's atmosphere, shifting the HZ outward for lower mass and inward for higher mass planets. Theory, as well as computer models suggest that atmospheric composition for water planets in the habitable