Polar Operational Environmental Satellites

The Polar-orbiting Operational Environmental Satellite (POES) project operates a constellation of weather satellites in polar orbits around the Earth. It is a joint effort between the National Oceanic and Atmospheric Administration (NOAA) and the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT). Spacecraft for the project are provided by NASA and the European Space Agency. NASA's Goddard Space Flight Center oversees the manufacture, integration and test of the NASA-provided TIROS satellites. The launch of the first polar-orbiting weather satellites in attempt to improve the accuracy and detail of weather analysis and forecasting began with FL. TIROS 1 (Television Infrared Observation Satellite) on April 1, 1960.

On-orbit satellite operation of these is performed by NOAA's Office of Satellite and Product Operations (OSPO). The POES constellation also includes an ESA-provided MetOp satellite operated by EUMETSAT. To protect the satellite from solar and terrestrial anomalies such as solar radiation belts and fluctuations of charged particles at altitude, the POES project is equipped with the Space Environment Monitor 2 (SEM-2) which provides awareness of these anomalies that may impair the operation of the satellite and its other sensors. The POES program will be superseded by the Joint Polar Satellite System (JPSS).

Each POES satellite completes roughly 14.1 orbits per day. Since the number of orbits per day is not an integer, the ground tracks do not repeat on a daily basis. The systems includes both morning and afternoon satellites which provide global coverage four times daily.

Data from the POES satellites support a broad range of environmental monitoring applications including weather analysis and forecasting, climate research and prediction, global sea surface temperature measurements, atmospheric soundings of temperature and humidity, ocean dynamics research, volcanic eruption monitoring, forest fire detection, global vegetation analysis, search and rescue, and many other applications.

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