The National Polar-orbiting Operational Environmental Satellite System (NPOESS) was to be the United States' next-generation satellite system that would monitor the Earth's weather, atmosphere, oceans, land, and near-space environment. NPOESS satellites were to host proven technologies and operational versions of sensors that were under operational-prototyping by NASA, at that time. The estimated launch date for the first NPOESS satellite, "C1" or "Charlie 1" was around 2013. Issues with sensor developments were the primary cited reason for delays and cost-overruns.
Artist's concept of a future NPOESS satellite, 2006.
Defense Meteorological Satellite Program
The Defense Meteorological Satellite Program (DMSP) monitors meteorological, oceanographic, and solar-terrestrial physics for the United States Department of Defense. The program is managed by the United States Space Force with on-orbit operations provided by the National Oceanic and Atmospheric Administration (NOAA). The mission of the satellites was revealed in March 1973. They provide cloud cover imagery from polar orbits that are Sun-synchronous at nominal altitude of 830 km (520 mi).
Artist rendition of a DMSP-5D2 satellite in orbit
DMSP images of Auroral bands circling north of Scandinavia in December 2010
Rendering of lights on Earth's surface created using DMSP observations between 1994 and 1995
DMSP and POES orbits shown in a GAO diagram.