Global ice loss increases at record rate
The rate at which ice is disappearing across the planet is speeding up, according to new research.
The rate at which ice is disappearing across the planet is speeding up, according to new research.
Earth Sciences
20 hours ago
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Large-scale land acquisitions by foreign investors, intended to improve global food security, had little to no benefit, increasing crop production in some areas while simultaneously threatening local food security in others, ...
Environment
Jan 19, 2021
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For the first time, scientists have successfully used satellite cameras coupled with deep learning to count animals in complex geographical landscapes, taking conservationists an important step forward in monitoring populations ...
Ecology
Jan 19, 2021
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A huge lake in Bolivia has almost entirely disappeared. Lake Poopó used to be the country's second largest, after Lake Titicaca, and just a few decades ago in its wet season peak it would stretch almost 70km end to end and ...
Environment
Jan 12, 2021
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Snugged up against the upper edges of the Canadian Arctic Archipelago and Greenland lies the oldest and thickest sea ice in the world, covering hundreds of thousands of square kilometers of ocean. Arctic sea ice grows and ...
Earth Sciences
Jan 06, 2021
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Latest images reveal that the A-68A iceberg has shattered into multiple pieces, with two large fragments of ice breaking off from the main berg and floating away in the open ocean. Scientists using satellite data have not ...
Earth Sciences
Dec 24, 2020
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Vessels known to have crew that are subject to forced labor behave in systematically different ways to the rest of the global fishing fleet, reveals a new paper published today in the scientific journal, Proceedings of the ...
Earth Sciences
Dec 21, 2020
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As Chile and Argentina witnessed the total solar eclipse on Dec. 14, 2020, unbeknownst to skywatchers, a little tiny speck was flying past the Sun—a recently discovered comet.
Space Exploration
Dec 18, 2020
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A team of researchers, using satellite data and other analytical tools, has identified companies fishing in high seas—waters that lie outside of national jurisdiction where fishing has raised fears about environmental and ...
Environment
Dec 18, 2020
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All hands have to be on deck if the world is going to tackle degradation, and one of the biggest emitters is also one of the least well known—international shipping. A 2018 study estimated that pollution emitted from cargo ...
Environment
Dec 02, 2020
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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