Asteroid will be visible from Eastern Europe, Asia, Australia

Washington - An asteroid half the size of a football pitch will make the closest pass ever observed from Earth on February 15, visibly streaking across the sky over Eastern Europe, Asia and Australia, astronomers said Thursday.

The near-Earth object, named 2012 DA14 after it was discovered last year by astronomers at an observatory in La Sagra in southern Spain, is 45 metres in diametre.

It will pass within 27.4 kilometres of Earth at 1924 GMT - roughly over Indonesia - and will be visible with the aid of binoculars from much of the eastern hemisphere, scientists from US space agency NASA said. Under clear skies, it will appear as a pinpoint of light moving against the stationary background of distant stars.

The flyby at bullet speed - 7.8 kilometres per second - will be the closest by such a large object in the decades since astronomers began cataloguing near-Earth objects or projected for known objects in the century ahead.

"For objects of this size, this is the closest encounter that we’re aware of," said Donald Yeomans, head of near-Earth objects at NASA’s Jet Propulsion Laboratory.

The asteroid’s path has been charted precisely enough to rule out a collision: "It cannot hit the Earth," Yeomans said.

Twenty years ago, the DA14 likely would have flown past Earth unnoticed, he said.

The space rock will pass 5 kilometres inside the orbits of many man-made satellites, but amage to such spacecraft is extremely unlikely. Nevertheless, NASA has alerted satellite operators, Yeomans said. The International Space Station is in no danger, NASA added.

The asteroid is roughly comparable in size to the meteor estimatedv to have caused the 1908 Tunguska event, when a massive blast laid waste to 2,000 square kilometres of uninhabited Siberian forest. DA14is likely a similar silicate rock as the Tunguska meteor and would probably explode in the atmosphere if it were bound for Earth.

Link with NASA video clips:http://www.nasa.gov/topics/solarsystem/features/asteroidflyby.html //DPA