Spacecraft Missions (cont.) NOAA POES: (Polar Operational Environmental Satellites) Because of the polar orbiting nature of the POES series satellites, these satellites are able to collect global data on a daily basis for a variety of land, ocean, and atmospheric applications. The Space Environment Monitor (SEM) that is flown on the NOAA POES (formerly TIROS) series of low-altitude (850 km), polar-orbiting spacecraft contains two sets of instruments that monitor the energetic charged-particle environment near Earth. The POES spacecraft provides useful data used to determine the level of auroral activity and it monitors energetic particles in Earth’s radiation belts that increase dramatically during magnetic storms.