Along Track Scanning Radiometer (ATSR)
The ATSR instruments flying on board the European Space Agency's ERS-1 and -2 satellites are advanced imaging sensors, which make accurate radiometric measurements in the thermal infrared and visible wavelengths.
Launch of ATSR-1 on ERS-1: 17th July 1991
Launch of ATSR-2 on ERS-2: 20th April 1995
From these, we can precisely measure sea-surface temperature, setting a new world standard (better than 0.3 K one sigma globally) for determining this parameter from space data. More about the ATSR programme