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Science and Health

Russia may send spacecraft to knock away asteroid

(Agencies)
Updated: 2009-12-31 10:16
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MOSCOW: Russia's space agency chief says a spacecraft may be dispatched to knock a large asteroid off course and reduce the chances of earth impact, even though US scientists say such a scenario is unlikely.

Anatoly Perminov told Golos Rossii radio on Wednesday that the space agency would hold a meeting soon to assess a mission to Apophis. He said his agency might eventually invite NASA, the European Space Agency, the Chinese space agency and others to join the project.

When the 270-meter (885-foot) asteroid was first discovered in 2004, astronomers estimated its chances of smashing into Earth in its first flyby, in 2029, at 1-in-37.

Further studies have ruled out the possibility of an impact in 2029, when the asteroid is expected to come no closer than 18,300 miles (29,450 kilometers) from Earth's surface, but they indicated a small possibility of a hit on subsequent encounters.

NASA had put the chances that Apophis could hit Earth in 2036 as 1-in-45,000. In October, after researchers recalculated the asteroid's path, the agency changed its estimate to 1-in-250,000.

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NASA said another close encounter in 2068 will involve a 1-in-330,000 chance of impact.

Don Yeomans, who heads NASA's Near-Earth Object Program, said better calculations of Apophis' path in several years "will almost certainly remove any possibility of an Earth collision" in 2036.

"While Apophis is almost certainly not a problem, I am encouraged that the Russian science community is willing to study the various deflection options that would be available in the event of a future Earth threatening encounter by an asteroid," Yeomans said in an e-mail Wednesday.

Without mentioning NASA's conclusions, Perminov said that he heard from a scientist that Apophis is getting closer and may hit the planet. "I don't remember exactly, but it seems to me it could hit the Earth by 2032," Perminov said.

"People's lives are at stake. We should pay several hundred million dollars and build a system that would allow us to prevent a collision, rather than sit and wait for it to happen and kill hundreds of thousands of people," Perminov said.

Scientists have long theorized about asteroid deflection strategies. Some have proposed sending a probe to circle around a dangerous asteroid to gradually change its trajectory. Others suggested sending a spacecraft to collide with the asteroid and alter its momentum, or hitting it with nuclear weapons.

Perminov wouldn't disclose any details of the project, saying they still need to be worked out. But he said the mission wouldn't require any nuclear explosions.

Hollywood action films "Deep Impact" and "Armageddon," have featured space missions scrambling to avoid catastrophic collisions. In both movies, space crews use nuclear bombs in an attempt to prevent collisions.

"Calculations show that it's possible to create a special purpose spacecraft within the time we have, which would help avoid the collision," Perminov said. "The threat of collision can be averted."

Boris Shustov, the director of the Institute of Astronomy under the Russian Academy of Sciences, hailed Perminov's statement as a signal that officials had come to recognize the danger posed by asteroids.

"Apophis is just a symbolic example, there are many other dangerous objects we know little about," he said, according to RIA Novosti news agency.

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