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Hipparcos |
Also found in: Acronyms, Wikipedia, Hutchinson | 0.10 sec. |
Hipparcosin full High Precision Parallax Collecting SatelliteSatellite launched by the European Space Agency that from 1989 to 1993 measured distances to more than 100,000 stars. Named after the 2nd-century-BC astronomer Hipparchus, who compiled the first known star catalog, the satellite was an orbiting telescope that could compute the position of a star to within 0.001 seconds of arc, or 20 times better than ground-based observations. These improved positions allowed much more accurate parallax determinations of stellar distances. Updated distances to Cepheid variables in particular refined the basis of the distance scale of the universe. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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To track the motion of nearby stars as they move across the sky, Benoit Famaey of the Free University of Brussels in Belgium and his collaborators used data from the European Space Agency's Hipparcos satellite, which ended its mission in 1993. If you accepted the Hipparcos result, then our ideas of how stars shine would be wrong," he said. 395 Sapiro, Guillermo 299 Sasisekharan, Ram 232 Satellite altimetry 31 Satellites 52, 216, 308, 398 Satellites, hipparcos 69 Saturn 388 Saunders, Scott 233 Saxon, Andrew 381 Scambos, Ted A. |
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