Nasa will repurposed a mothballed infrared space telescope to hunt for asteroids, officials have confirmed.
The Wide-field Infrared Survey Explorer, or WISE, telescope will be reactivated for a three-year mission to search for potentially dangerous asteroids on a collision course with Earth, as well as hunting for targets for a future mission to send a robotic spacecraft to rendezvous with a small asteroid and relocate all or part of it into a high orbit around the moon.
Launched in December 2009, the WISE telescope spent 13 months scouting for tell-tale infrared signs of asteroids, stars, distant galaxies and other celestial objects, especially those too dim to radiate in visible light.
As part of its all-sky mapping mission, WISE observed more than 34,000 asteroids in the main asteroid belt between Mars and Jupiter and another 135 asteroids in orbits that come close to Earth. Overall, scientists catalogued more than 560 million objects with WISE.
Most of the telescope's instruments were turned off when its primary mission was completed in February 2011, but Nasa now plans to bring WISE out of hibernation next month and operate it for another three years, at a cost of about $5m per year, said Nasa spokesman Dwayne Brown yesterday.
"After a quick checkout, we're going to hit the ground running," WISE astronomer Amy Mainzer, with NASA's Jet Propulsion Laboratory in Pasadena, California, said in a statement.
Nasa has already found about 95 per cent of the near-Earth asteroids that are 0.62 miles (1 km) or larger in diameter. The agency is about halfway through a 15-year effort to find 90 per cent of all near-Earth objects that are as small as about 140m in diameter.
The search took on a note of urgency after a small asteroid blasted through the skies above Chelyabinsk,Russia, in February 2013 and exploded with 20- to 30 times the force of the Hiroshima atomic bomb. More than 1,500 people were injured by flying glass and debris.
Later that same day, a much larger but unrelated asteroid soared closer to Earth than the networks of communication satellites that ring the planet.
The events prompted Congressional hearings and new calls for Nasa and other agencies to step up their asteroid detection initiatives.
The Obama administration proposes to double Nasa's $20m Near-Earth Objects detection programs for the 2014 fiscal year beginning 1 October.