The DMSP is a Department of Defense (DoD) program run by the Air Force Space and Missile Systems Center (SMC). The DMSP designs, builds, launches, and maintains satellites monitoring the meteorological, oceanographic, and solar-terrestrial physics environments. Each DMSP satellite has a 101 minute, sun-synchronous near-polar orbit at an altitude of 830km above the surface of the earth. The visible and infrared sensors (OLS) collect images across a 3000km swath, providing global coverage twice per day. The combination of day/night and dawn/dusk satellites allows monitoring of global information such as clouds every 6 hours. The microwave imager (MI) and sounders (T1, T2) cover one half the width of the visible and infrared swath. These instruments cover polar regions at least twice and the equatorial region once per day. The space environment sensors (J4, M, IES) record along-track plasma densities, velocities, composition and drifts. The data from the DMSP satellites are received and used at operational centers continuously. The data are sent to the Earth Observation Group (EOG) within the National Center for Environmental Information (NCEI)'s Solar Terrestrial Physics (STP) Division. (NCEI/STP/EOG) by the US Air Force 557th Weather Wing for creation of an archive. NESDIS operates 5 DMSP satellites. Currently, data from 4 satellites are added to the archive each day.