This conceptual image shows the Upper Atmosphere Research Satellite, launched September 15, 1991, by the space shuttle Discovery. Originally designed for a 3-year mission, UARS measured chemical compounds found in the ozone layer, wind and temperature in the stratosphere, as well as the energy input from the Sun. Together, these measurements helped define the role of Earth's upper atmosphere in climate and climate variability. UARS was decommissioned December 14, 2005.