Nimbus 3

Nimbus 3 was launched on April 14, 1969 as a NASA meteorological research observatory. Infrared spectrometers and radiometers investigated atmospheric temperature profiles and Earth’s emission spectrum, while visible imaging, solar-ultraviolet monitoring and remote-data collection broadened the experiment set. It also tested SNAP-19 radioisotope thermoelectric power. Individual instruments stopped at different times in 1969–1970. Failure of a rear horizon scanner in September 1970 prevented attitude control adequate for most observations, and all spacecraft operations ended on January 22, 1972. The mission’s operational end should be distinguished from the earlier loss of key scientific measurements.