Using machine learning to find space rocks in Antarctica

A team of researchers from Université libre de Bruxelles, Delft University of Technology and Vrije Universiteit Brussel used AI technology to find meteorites hidden in Antarctic ice. The group describes how their AI system ...

Six questions to understand the sixth warmest year on record

2021 tied with 2018 as the sixth warmest year on a record that extends back to 1880, according to NASA's annual analysis of global average temperatures. The year contributed to an unprecedented, but well-understood trend ...

NASA estimates metrics of exploding meteor that shook ground

A meteor that caused an earthshaking boom over suburban Pittsburgh on New Year's Day exploded in the atmosphere with an energy blast equivalent to an estimated 30 tons (27,216 kilograms) of TNT, officials said.

Satellite data used to assess tornado damage, understand storms

As people across the Midwestern U.S. take stock of the devastation from a Dec. 10 trail of tornados that blew across the region, data and images from NASA Earth-observing satellites aid first responders and recovery agencies ...

Red Sea bioregions show changing blooms

Red Sea phytoplankton blooms change seasonally and interannually in response to climatic events. A KAUST study has analyzed satellite data over two decades and its findings will underpin other investigations into how climate ...

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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