Since 1960, NOAA has operated a fleet of Polar-orbiting Environmental Satellites called POES, complimented by the higher altitude (36,000km) Geostationary Operational Environmental Satellites (GOES). The stationary GOES satellites give a constant view from two points in space, while the polar-orbiting NOAA-N Prime circles the Earth at a lower altitude (860km) once every 102 minutes. These two systems provide continuous data about the global atmosphere. Note: Animation showing the orbit paths for both the GOES and POES spacecraft. Animator: Chris Meaney (HTSI). Producer: Silvia Stoyanova (UMBC). Platforms/Sensors/Data Sets: GOES, NOAA-N Prime/TIROS, NOAA-N Prime/SARSAT.