Earth observation satellite
Earth observation satellites or Earth remote sensing satellites are satellites specifically designed for Earth observation from orbit, similar to spy satellites but intended for non-military uses such as environmental monitoring, meteorology, map making etc. 
The first occurrence of satellite remote sensing can be dated to the launch of the first artificial satellite, Sputnik 1, by the Soviet Union on October 4, 1957. Sputnik 1 sent back radio signals, which scientists used to study the ionosphere.
NASA launched the first American satellite, Explorer 1, in January 31, 1958. The information sent back from its radiation detector led to the discovery of the Earth's Van Allen radiation belts.
The TIROS-1 spacecraft, launched on April 1, 1960 as part of NASA's TIROS (Television Infrared Observation Satellite) Program, sent back the first television footage of weather patterns to be taken from space.
, more than 150 Earth observation satellites were in orbit, recording data with both passive and active sensors and acquiring more than 10 terabits of data daily.
TV-SAT 1
TV-SAT 1 was launched by Arianespace using an Ariane 2 rocket flying from ELA-1 at Kourou. The launch took place at 02:19:00 GMT on 21 November 1987. It was the first Spacebus 300 satellite to be launched. Immediately after launch, one of its solar panels failed to deploy, and as a result of this the main uplink antenna, which was located behind the solar panel, could not deploy either. This failure was later established to have been the result of two hold-down bolts, which should have been removed prior to launch, being left on the satellite.