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Soil Moisture Active Passive Experiment

Advanced Along-Track Scanning Radiometer (AATSR)


Advanced Along-Track Scanning Radiometer (AATSR) is one of the Announcement of Opportunity (AO) instruments on board the European Space Agency (ESA) satellite ENVISAT. It is the most recent in a series of instruments designed primarily to measure Sea Surface Temperature (SST), following on from ATSR-1 and ATSR-2 on board ERS-1 and ERS-2. AATSR data have a resolution of 1 km at nadir, and are derived from measurements of reflected and emitted radiation taken at the following wavelengths: 0.55 µm, 0.66 µm, 0.87 µm, 1.6 µm, 3.7 µm, 11 µm and 12 µm. Special features of the AATSR instrument include its use of a conical scan to give a dual-view of the Earth's surface, on-board calibration targets and use of mechanical coolers to maintain the thermal environment necessary for optimal operation of the infrared detectors. AATSR data can be downloaded from ESA.




Advanced Along-Track Scanning Radiometer (AATSR)



Launch date

1st, Mar. 2002

Design life

3 years with a goal of 5 years


Sun-synchronous polar orbit (SSO): Nominal reference orbit of mean altitude 800km, 35 days repeat cycle, 10:00am mean local solar time (MLST) descending node, 98.55°. inclination. [envisat.esa.int]

Spacecraft operations control centre



Sea surface temperature: <0.5K over 0.5 deg x 0.5 deg (lat/long) area with 80% cloud cover Land surface temperature: 0.1K (relative)

Swath (km)



VIS - NIR: 0.555, 0.659, 0.865 micrometers, SWIR: 1.6 micrometers, MWIR: 3.7 micrometers, TIR: 10.85, 12 micrometers

Spatial resolution (m)

IR ocean channels: 1km x 1km, Visible land channels: 1km x 1km

Temporal resolution

35 days repeat cycle






Created: February 2016
Last Modified: June 2016
Maintainer: Xiaoling Wu, xiaoling.wu@monash.edu