Feb 10 2009
From The Space Library
A Russian satellite launched in 1993, and that engineers believed to be nonfunctioning, crashed into an Iridium commercial satellite that had been in orbit since 1997. The collision marked the first instance of high-speed impact between two intact spacecraft. At the time of the event, Iridium had a system of 65 active satellites relaying calls from portable telephones approximately twice the size of regular mobile phones. Iridium was serving approximately 300,000 subscribers, including one of its largest cellular subscribers, the U.S. Department of Defense (DOD). The loss of the satellite caused brief, occasional outages in service. Iridium planned to replace the lost satellite within 30 days with one of eight in-orbit spares.communications satellites, which typically orbit at high altitudes and travel separately, rarely collide. However, Iridium satellites traveled fast, at a low orbit. The Iridium collision, which occurred approximately 500 miles (805 kilometers) from Earth, created a huge debris field. Nicholas L. Johnson of NASA’s Johnson Space Center (JSC) explained that the risk of the ISS encountering debris was low, because the space station is 215 miles (346 kilometers) from Earth.
Marcia Dunn for the Associated Press, “Big Satellites Collide 500 Miles Over Siberia,” 12 February 2009; Traci Watson, “Two Satellites Collide 500 Miles Over Siberia,” USA Today, 12 February 2009.
NASA announced that it had designated 2009 as the International Year of Astronomy, to commemorate the anniversary of the beginning of modern astronomy in 1609, when Galileo first used a telescope to view the heavens. As part of the yearlong celebration, NASA planned to release images from its Great Observatories—Hubble Space Telescope (HST), Spitzer Space Telescope (SST), and Chandra X-ray Observatory—to museums, nature centers, planetariums, and schools across the country. NASA would make the images public between 14 and 28 February 2009, in conjunction with Galileo’s 15 February birthday. Selected sites would also unveil a large 9-square-foot (2.7-square-meter) print of the spiral galaxy Messier 101. NASA had created the print by combining images of Messier 101—HST’s optical view, SST’s infrared view, and Chandra’s x-ray view. Describing the image created from the three views, Hashima Hasan, Lead Scientist for the International Year of Astronomy at NASA Headquarters, said that one might see such an image if one could use one’s eyes, night-vision goggles, and x-ray vision simultaneously. The selected sites would also display individual images from each observatory. HST’s visible-light view of Messier 101, known as the Pinwheel Galaxy, revealed the swirls of bright stars and glowing gas that had earned the galaxy its nickname. Spitzer’s infrared-light image peered into those spiral arms, showing where dense clouds collapse to form stars. Chandra’s x-ray image uncovered high-energy features of Messier 101, such as remnants of exploded stars or matter moving around black holes.
NASA, “NASA’s Great Observatories Celebrate International Year of Astronomy,” news release 09-026, 10 February 2009, http://www.nasa.gov/home/hqnews/2009/feb/HQ_09-026_IYOA.html (accessed 28 February 2011).
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