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Тематические разделы => Прикладная космонавтика => Тема начата: Salo от 31.07.2012 21:50:23

Название: Европейские малые КА
Отправлено: Salo от 31.07.2012 21:50:23
http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_07_30_2012_p39-479084.xml&p=1

Europe Has A Busy Smallsat Manifest

By Amy Svitak
Source: Aviation Week & Space Technology

(https://img.novosti-kosmonavtiki.ru/310058.jpg)
ExactView-1-SSTL

July 30, 2012

Amy Svitak Paris

Europe has long been a hotbed of small-spacecraft development. Now investments in the U.K., France and Germany are paying off, and an increasingly sophisticated fleet of smallsats is being used for Earth observation, science and military applications.

Next year the European Space Agency (ESA) is preparing to launch its Proba V satellite atop the new Vega light launcher from the European spaceport at Kourou, French Guiana. The 160-kg (352-lb.) microsat is based on the agency's Proba technology-demonstration platform, but is designed to fly an operational payload that will monitor global vegetation growth.

Current vegetation monitoring instruments aboard France's Spot-4 and Spot-5 satellites have mapped changes in worldwide vegetation to provide data on crop yields, droughts, desertification and deforestation. However, the two satellites are operating well beyond their design life, and no immediate follow-on capability is planned until ESA launches the Sentinel-3 Earth observation satellite in 2014 under the Global Monitoring for Environment and Security (GMES) program. To ensure data continuity in the interim, ESA and the Belgian Federal Science Policy Office are investing in a scaled-down version of the Spot vegetation-monitoring instrument that will fly aboard Proba V.

In France, the CNES space agency continues to rely on its lightweight Myriade platform for quick, low-cost science and technology demonstration missions. Weighing less than 200 kg, the Myriade bus was conceived in the mid-1990s as a complement to CNES's Proteus mini-satellite platform in the 500-kg class.

Developed with EADS-Astrium to serve as the space segment of a turnkey mission system, Myriade comes with a ground system for data acquisition and command-and-control, as well as tools for mission analysis, spacecraft design and system validation.

Since 2004, 17 Myriade-based microsatellites have been placed in orbit. The first, Demeter, was used to measure the Earth's magnetic environment and forecast earthquakes. The spacecraft was deorbited in mid-2010, leaving more than six years of scientific data on the link between ionospheric perturbations and seismic and volcanic activity.

Demeter was followed by Parasol in December 2004, a mission to study the properties of aerosols and clouds of the Earth's atmosphere, followed by the Picard solar-variability mission launched in June 2010.

Two additional CNES science missions—Taranis and Microscope—are slated to launch in the next few years. CNES recently signed a contract with Arianespace that would see Taranis lofted atop a Russian Soyuz or European Vega rocket in 2016 from Kourou. The 200-kg spacecraft, which is designed to study the magnetosphere-ionosphere-atmosphere coupling via transient processes, would be launched into a quasi-Sun-synchronous orbit at an altitude of 700 km (435 mi.).

In addition to Taranis, the contract includes an option to launch two additional satellites: Microscope, which will test the validity of Galileo's Equivalence Principle in the vacuum of space; and Merlin, a €120-million ($144-million) project funded by CNES and the German Aerospace Center (DLR) that will incorporate a German lidar instrument. Both nations will collaborate on the payload ground segment and data analysis.

Slated to launch in 2016, Merlin will be the first of a second-generation microsatellite platform, dubbed Myriade Evolution, designed to boost spacecraft performance. The new bus, which is being developed with €40 million in French public bond money, is intended to double the current platform's 50-kg payload capacity and 50-watt power generation on orbit.

Following Merlin, France is planning to loft in 2018 a carbon-dioxide-monitoring satellite dubbed MicroCarb that will be based on the new Myriade Evolution platform.

France's armaments agency (DGA) is also using Myriade to experiment with formation-flying and swarming capabilities. The Astrium-built Essaim constellation, which launched with Parasol in December 2004, was designed to study the electromagnetic environment on the ground in military frequency bands with a swarm of four 120-kg spacecraft separated by a few hundred kilometers.

DGA's Spirale demo, developed by Thales Alenia Space and Astrium and launched in February 2009, comprises two satellites that collect infrared images of terrestrial backgrounds and serves as a precursor to development of a space-based operational early warning system in France.

More recently, CNES launched the Astrium-built Elisa electronic intelligence satellites for DGA in December atop a European variant of the Soyuz rocket from Kourou. The four-satellite demonstration cost €115 million to develop and launch, and is aimed at locating and identifying radar stations. The 120-kg satellites are operating in a polar, low Earth orbit at an altitude of 694 km, and could pave the way for an operational program.

Astrium, through its partnership with CNES, offers a commercial version of Myriade dubbed AstroSat100. Three missions based on the platform are currently in orbit, including Chile's SSOT Earth-observation satellite, which launched with Elisa last year; Algeria's two-satellite Alsat Earth-observation system; and a Vietnamese optical satellite, VNREDSat-1.

In July, DLR lofted its TET-1 satellite, the first in a series based on Germany's BIRD (Bispectral InfraredDetection) small-satellite platform that will support DLR's On-Orbit Verification program. Developed by Astro- und Feinwerktechnik Adlershof GmbH, the 120-kg spacecraft bus is loaded with 11 experiments operating in a Sun-synchronous orbit at an altitude of 500 km, including a camera capable of detecting forest fires.

While roughly the same size as the experimental BIRD platform, TET-1 is a more capable spacecraft for operational missions, says DLR Chairman Johann-Dietrich Woerner. "We now have TET-1, but hope to have more of these," he says. "In order to get better revisit time, we need more than one satellite to give us information as close as possible to real time."

TET-1 was one of five small satellites launched July 22 on a Soyuz rocket from Baikonur Cosmodrome in Kazakhstan. The others were two Russian Earth-monitoring satellites, Canopus-B and MKA-PN1; the Belarusian BKA spacecraft; and exactView-1, a Canadian maritime-monitoring spacecraft built by U.K.-based Surrey Satellite Technology Ltd. (SSTL).

A spinoff from the University of Surrey's space technology school, SSTL started out in the mid-1980s catering to nations in the market for small research satellites. Today SSTL is a booming business that is wholly owned by Astrium, and is building the payloads for Europe's 22 operational Galileo satellites to be lofted starting in 2013 (see p. 42).