|XMM - |
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ESA's X-ray Multi-Mirror space observatory was the biggest science satellite ever built in Europe. The XMM was a three-axis stabilised spacecraft with a pointing accuracy of 1 arcsec. The satellite consisted of a service module bearing the X-ray Mirror Modules, propulsion and electrical systems, a long telescope tube, and the focal plane assembly carrying the science instruments. The Prime contractor was DaimlerChrysler Aerospace Dornier Satellitensysteme, Friedrichshafen, Germany; subcontractors included 46 companies from 14 European countries and one in the United States. Media Lario, Como, Italy, developed the X-ray Mirror Modules.
XMM was designed to operate for 10 years. The spacecraft's X-ray optics covered a spectral range of 1-120 nanometres (12keV-0.1keV). The telescope consisted of three barrel-shaped Mirror Modules, each containing 58 "Wolter-type" wafer-thin concentric mirrors, 0.3 m to 0.7 m in diameter and 0.6 m in length. The total collecting area was 4300 cm2 at 1.5 keV, 1800 cm2 at 8 keV. The focal length of the telescope was 7.5 m and resolution was 5 arcsec (full width half-maximum), 14 arcsec (half energy width) at all wavelengths. Each X-ray Mirror Module has a mass of 500 kg.
There main science instruments on board XMM included:
The XMM spacecraft was placed in a 48-hour elliptical orbit around the Earth (7,000 km x 114,000 km at 40 degree inclinaton). On each orbit, after the satellite passed through the Earth's radiation belts, astronomers had the observatory at their disposal for some 40 hours.
The XMM spacecraft was controlled by the European Space Operations Centre (ESOC, Darmstadt Germany) using ground stations at Perth (Australia) and Kourou (French Guiana). The XMM Science Operations Centre situated at VILSPA in Villafranca, Spain, managed observation requests and received XMM data. The XMM Survey Science Centre (SSC), at Leicester University UK, processed, archived and correlated all XMM observations with existing sky data held elsewhere in the world.
The XMM mission was the second Cornerstone mission of ESA's Long-Term Space Science programme. It was proposed by the Agency's Science Programme Committee in 1984 and was approved by the ESA Council of Ministers held in Rome in January 1985. After the setting up in January 1993 of the XMM Project team based at the ESTEC Technical Centre in Noordwijk, Netherlands, and selection of the prime contractor in October 1994, the development phase began in March 1996 and actual construction of the spacecraft started in March 1997. Satellite integration and testing was completed in September 1999. The project, under direct ESA management, has been achieved within the allocated budget of 689 Million Euro at 1999 economic conditions (covering satellite design and construction, launch by Ariane-5 and science mission operations during the first two years.)
Total Length: 10.0 m. Total Mass: 3,800 kg.
The XMM mission was the second Cornerstone mission of ESA's Long-Term Space Science programme. It was proposed by the Agency's Science Programme Committee in 1984 and was approved by the ESA Council of Ministers held in Rome.
ESA's X-ray Multi-Mirror space observatory was the biggest science satellite ever built in Europe. Complementary in characteristics to NASA's Chandra satellite, the spacecraft were expected to make major new astronomical discoveries.