[A little bit more info on this strange event.] FEBRUARY 12, 2009, 1:25 P.M. ET
Satellites Destroyed in Orbital Collision By ANDY PASZTOR Wall Street Journal http://online.wsj.com/article/SB123445538732677987.html A commercial satellite owned by a U.S. company was destroyed in a collision with a defunct Russian military satellite in what NASA said was the first such accident in orbit, raising new concerns about the dangers of space debris. The crash, which happened Tuesday in low-earth orbit, involved one of the satellites owned by closely held Iridium Satellite LLC and a crippled Russian military satellite that apparently stopped functioning years ago, according to U.S. government and satellite-industry officials. The collision created two large clouds of debris floating roughly 480 miles above Siberia, and prompted space scientists and engineers to assess the likelihood of further collisions. The accident could have implications for U.S. space budgets and policy, partly because it comes amid a Pentagon campaign to increase spending on systems to protect U.S. high-tech space hardware by keeping better track of the thousands of pieces of debris and other satellites circling the Earth. As more and more satellites are blasted into orbit, the challenges of keeping them from hitting debris or each other are growing. Military planners also worry about enemies jamming, disabling or potentially even ramming U.S. satellites. Industry officials say Iridium has identified the Russian craft as a Cosmos series satellite launched in 1993, weighing more than a ton and including an onboard nuclear reactor. That couldn't be independently verified. Experts have said the chance of radioactive debris surviving a fall through the atmosphere and reaching inhabited areas is very small. The Russian Embassy couldn't be reached for comment. More than 220 active commercial satellites now orbit the globe, in addition to hundreds of military, spy and scientific satellites. Commercial satellites provide businesses with everything from data and video transmissions to support for consumer navigation devices. The Russian craft was being monitored by Pentagon organizations that keep track of space debris in order to prevent in-orbit collisions from damaging or destroying both commercial and government satellites. The National Aeronautics and Space Administration and the Pentagon track more than 10,000 pieces of high-speed debris, some no larger than a football. NASA officials said the collision posed little risk to the international space station, the Associated Press reported. The station orbits about 270 miles below the collision course. There also should be no danger to the space shuttle set to launch with seven astronauts on Feb. 22, officials said, but that will be re-evaluated in the coming days. Cosmos satellites have been designed for various uses, from spy missions to missile-warning systems to securing military communications. They have caused a number of scary incidents over the years, including a 1991 collision between one defunct model and debris from another; a near-collision with the space shuttle the same year; and another that crashed into Canadian wilderness in 1978. Pentagon officials will face a barrage of questions about how they missed such an impending collision with an intact satellite, according to Tim Farrar, a satellite consultant familiar with Iridium. Commercial satellites are "routinely repositioned to avoid potential collision with smaller pieces of debris," said Mr. Farrar. Pentagon brass, satellite industry executives and NASA leaders for years have publicly expressed concern about the dangers of orbital debris. But the odds of a direct hit between satellites were considered so small as to be basically unthinkable. The ground-based and space-based reconnaissance tools available to the Pentagon generally were considered adequate to keep close track of larger objects. Recently, U.S. and European operators began reviewing contingency plans to move some telecommunications satellites away from a pair that are malfunctioning. Space collision worries gained momentum in January 2007, when China used a relatively simple antisatellite weapon to knock down one of its aged weather satellites. NASA said there have been four earlier instances of accidental collisions in orbit, generally involving rocket parts and other debris. None involved a full-size satellite. When satellites reach the end of their useful lives they often are parked in remote orbits where they are unlikely to endanger working satellites. But if a satellite's onboard computers or other systems fail, or it runs out of battery power, it can be difficult for ground operators to maintain control. Iridium, of Bethesda, Md., uses more than 60 satellites to provide voice and data services for about 300,000 subscribers globally. It said the collision has "minimal impact" on service due to its backup capacity. ================================================= George Antunes Voice (713) 743-3923 Associate Professor Fax (713) 743-3927 Political Science Internet: antunes at uh dot edu University of Houston Houston, TX 77204-3011 *********************************** * POST TO [email protected] * *********************************** Medianews mailing list [email protected] http://lists.etskywarn.net/mailman/listinfo/medianews
