NASA data shows Humberto now post-tropical

Satellite data has confirmed that Humberto, once a major hurricane is now a post-tropical cyclone. NASA's Terra Satellite provided a visible image of Post-Tropical Cyclone Humberto as it continued moving in an easterly direction ...

Just how much of the Amazon is burning?

You've seen it all over the news: Fires in the Amazon and throughout South America have been raging for weeks, sparking dire predictions about climate change, criticism of the Brazilian government over increased deforestation, ...

Satellite data can reveal fire susceptibility in peatlands

When large areas of carbon-rich soil catch fire, the blaze emits massive amounts of carbon into the atmosphere and creates a thick haze. These blazes can usher in long-term climate impacts that affect the whole planet and ...

New open cluster discovered using Gaia

Using data from ESA's Gaia satellite, German astronomers have detected a new open cluster in the Milky Way galaxy. The newly found cluster, designated Gaia 8, consists of about 100 stars, most likely including the Beta Lyrae ...

NASA finds Kiko weakening in the Eastern Pacific

NASA's Aqua satellite provided forecasters at the National Hurricane Center with infrared data and cloud top temperature information on Hurricane Kiko. Wind shear was affecting the storm and had closed the eye.

Indonesia forest fires surge, stoking global warming fears

The number of blazes in Indonesia's rainforests has jumped sharply, satellite data showed Thursday, spreading smog across Southeast Asia and adding to concerns about the impact of increasing wildfire outbreaks worldwide on ...

Using machine learning for rewilding

There may not be an obvious connection between rewilding and machine learning, but as highlighted today at ESA's ɸ-week, a project in the Netherlands uses satellite data and new digital technology to understand how a nature ...

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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