Defense Meteorological Satellite Program

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An artist’s impression showing one of the Block 5D-2 spacecraft in orbit. Eight were launched between 1987 and 2003.

Rendering of lights on Earth's surface created using DMSP observations

The Defense Meteorological Satellite Program (DMSP) monitors meteorological, oceanographic, and solar-terrestrial physics for the United States Department of Defense. The program is now run by the National Oceanic and Atmospheric Administration.^[1] The (originally classified) mission of the satellites were revealed in March 1973. They provide cloud cover imagery from polar orbits that are sun-synchronous at nominal altitude of 450 nautical miles.^[2]

[edit] History

During the 1960s, one of most important projects the United States civil space program was involved in and dealt with meteorology and weather forecasting. Unbeknownst to many, the U.S. military services were also starting up a weather satellite program. This program, the DMSP, would relay important weather and climate data to the warfighter for more effective military operations. From the onset of the DMSP program, knowledge of its existence was limited to 'need-to-know' personnel. The United States Congress had assigned a substantial budget towards the civil weather satellite program; if knowledge of a second military program came out, it would have been hard for the military to justify it.

Initial operations of early DMSP systems provided radio return of cloud-cover imagery for planning of US high-resolution photographic reconnaissance and surveillance missions, which utilized film-return systems. DMSP satellites operated in a sun-synchronous orbit; passing over the north and south poles, the satellite would 'see' different strips of the Earth at the same local time each day. The DMSP satellites had periods of roughly 101 minutes, so they would orbit the Earth 14.3 times in 24 hours. This period combined with the sun-synchronous orbit would have the satellite pass over the whole surface of the planet twice a day.

The images acquired were relayed to the Earth and received by two command and readout stations established at retired Nike missile sites located near Fairchild Air Force Base, Washington and Loring Air Force Base, Maine.^[3] From these sites, the images were then sent to Air Force Global Weather Central (AFGWC) located at Offutt Air Force Base, Nebraska. Images would then be processed, forming a mosaic representing the cloud patterns that were observed from the orbiting satellites. Meteorologists could then provide flight crews and other commanders with up-to-date observations for their particular missions. Further advancements enabled data to be collected in the visual spectrum down to a half-moonlit scene. Infrared processing enabled night viewing. Other enhancements increased onboard processing by including multiple onboard computers and expanded power requirements.

Now in its fifth decade of service, the DMSP has proven itself to be a valuable tool in scheduling and protecting military operations on land, at sea, and in the air. In December 1972, DMSP data was declassified and made available to the civil/scientific community. On June 1, 1998 the control and maintenance of the satellites were transferred to NOAA in order to reduce costs.

[edit] Launch history

The first successful launch of a DMSP spacecraft used a Scout X-2 rocket lifting off from Point Arguello near Vandenberg Air Force Base on 1962-08-23.^[4][5] Other early launches were conducted using Thor launch vehicles, with Altair or Burner II upper stages. Eight satellites were launched using Atlas E launch vehicles between 1982 and 1995. Three were launched aboard Titan II vehicles between 1997 and 2003. One has been launched on a Delta IV rocket.

This table is incomplete and may require expansion and/or cleanup. Please improve the article, or discuss the issue on the talk page.

[edit] References

[edit] See also

• NPOESS - the National Polar-orbiting Operational Environmental Satellite System

[edit] External links

• National Geophysical Data Center archive of DMSP data
• Air Force Fact Sheet
• The High Ground - DMSP
• Air Force Research Lab Horizons magazine article
• Air Force news article
• SSEIS ionospheric instrument data page