NASA finds heavy rainfall in Tropical Storm Cristobal

The third tropical cyclone of the Atlantic Ocean basin has been generating large amounts of rainfall over Mexico's Yucatan and parts of Central America. Using satellite data, NASA analyzed that heavy rainfall and provided ...

Football pitch of rainforest destroyed every six seconds

Vast tracts of pristine rainforest on three continents went up in smoke last year, with an area roughly the size of Switzerland cut down or burned to make way for cattle and commercial crops, researchers said Tuesday.

Climate change will turn coastal Antarctica green, say scientists

Scientists have created the first ever large-scale map of microscopic algae as they bloomed across the surface of snow along the Antarctic Peninsula coast. Results indicate that this 'green snow' is likely to spread as global ...

NASA-NOAA satellite sees Amphan's eye obscured

Early on May 18, 2020, Tropical Cyclone Amphan was a Category 5 storm in the Northern Indian Ocean. On May 19, satellite data from NASA-NOAA's Suomi NPP satellite revealed that the storm has weakened and the eye was covered ...

The storm chasers making life-saving forecasts

Weather forecasters in Africa are getting access to satellite data that will allow them to track the path and severity of developing storms—and reduce the death toll from extreme weather events.

Czech Republic drought visible from space

The prolonged period of dry weather in the Czech Republic has resulted in what experts are calling the 'worst drought in 500 years.' Scientists are using ESA satellite data to monitor the drought that's gripped the country.

Satellites eye typhoon Vongfong landfall in the Philippines

NASA and NOAA satellites have been providing forecasters with satellite data that showed the strength and extent of Typhoon Vongfong as it made landfall in the Philippines and continued to track through the country. Warnings ...

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Satellite Data System

The Satellite Data System (SDS) is a system of United States military communications satellites. At least three generations have been used: SDS-1 from 1976 to 1987; SDS-2 from 1989 to 1996; SDS-3 from 1998 to the present. SDS satellites have a highly elliptical orbit, going from about 300 kilometers at perigee to roughly 39,000 km at apogee in order to allow communications with polar stations that cannot contact geosynchronous satellites. The high apogee meant that the polar regions were visible for long amounts of time, and only two satellites were required in order to achieve constant communications ability. The SDS satellites were constructed by Hughes Aircraft.

The primary purpose of the SDS satellites is to relay imagery from low-flying reconnaissance satellites to ground stations in the United States.

Each SDS-1 satellite had 12 channels available for ultra-high frequency communication. They were cylindrical in shape, roughly 25 feet (7.6 m) long. 980 watts of electrical power were available from solar panels and batteries. The SDS-1 had a mass of 1385 pounds (630 kilograms) and was launched on Titan-3B rockets. The SDS-1 satellites had similar orbits to the Air Force's Jumpseat ELINT satellites.

The SDS-2 is significantly more massive at 5150 pounds (2335 kg), with three separate communication dishes, including one for a K band downlink. Two dishes are 15 feet (4.5 meters) in diameter, while the third is 6.6 feet (2 m) in diameter. The solar arrays generate 1238 watts of power. It is believed that the Space Shuttle has been used to launch several satellites, possibly on missions STS-28, STS-38, and STS-53. Other launches have used the Titan-4 rocket.

Quasar is the rumored code name for the communications satellite.

A recent Quasar may have been launched into a high-apogee orbit from Cape Canaveral on August 31, 2004 by an Atlas 2AS rocket.

This text uses material from Wikipedia, licensed under CC BY-SA