DMSP-F18

DMSP-F18 (Defense Meteorological Satellite Program F-18) is a Block 5D-3 satellite operated by the U.S. Space Force with NOAA as data and operations partner, launched on 2009-10-18.^[1][2] It flies a sun-synchronous near-polar orbit at approximately 830-850 km altitude with a 04:30 descending equator crossing.^[2][3] The satellite carries seven instruments: the Operational Linescan System (OLS) for visible and infrared cloud imaging; the Special Sensor Microwave Imager/Sounder (SSMIS) for passive microwave atmospheric sounding and surface parameter retrieval; the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) and Ultraviolet Limb Imager (SSULI) for ionospheric ultraviolet imaging; the Special Sensor Ion-Electron Scintillation Sensor (SSI/ES-3) for ionospheric plasma measurement; the Special Sensor Magnetometer (SSM) Boom for space-weather magnetometry; and the Special Sensor for Precipitating Particles (SSJ/5) for particle spectrometry.^[3] WMO OSCAR recorded F18 as operational with a September 2026 EOL; the SSMIS instrument is degraded, while several other payloads remain active.^[3] DMSP-F18 supports global weather forecasting, oceanographic observation, and space-weather monitoring for Department of Defense and civil users.^[1][2]