Nimbus 4 Selective Chopper Radiometer, optics housing plus electronics module (flight spare), 1968-1970

Nimbus 4 Selective Chopper Radiometer (SCR), optics housing, plus electronics module (flight spare), 1968-1970, developed in partnership between Oxford University (Clarendon Laboratory) and the University of Reading, to measure atmospheric temperatures from space. The SCR measured infrared radiation emitted by carbon dioxide. The SCR was flown on the Nimbus 4 satellite as well as the Nimbus 5. It was the first instrument of its kind to provide global measurements of atmospheric temperature without interference from clouds. Nimbus 4 launched on 8 April 1970 by a Thor-Agena rocket from Vandenberg AIr Force Base in California, USA. The spacecraft operated until September 1980.

NASA's Nimbus programme was a pioneering satellite programme for meteorological research and development. The seven satellites launched during a 14-year period tested sensors and collected data on Earth's atmosphere for 30 years. It served as the basis for modern Earth-observing satellites. One of the most significant contributions of the Nimbus programme was - for the first time - providing scientsits with direct observations of the amount of solar radiation entering and exiting the Earth system. This helped to verify and refine early climate models.