A mile-wide asteroid will skim past the Earth tomorrow in a cosmic close shave. The space rock, dubbed 2006 VV2, was only discovered in November by LINEAR, an automated telescope scouring the skies for such objects.

Astronomers say the asteroid will appear to move at twice the speed of the Moon across the sky as it passes through the constellations of the Great Bear and Leo.

It is too small to be seen with the naked eye but can be seen in stargazers’ backyard telescopes. Amateurs in western Europe will be watching on Saturday night for a possible occultation of a magnitude 7.5 star.

Nasa are planning to bounce radar signals off the asteroid from its Goldstone radio telescope in California’s Mojave desert. That will give them more accurate information about the asteroid’s size and shape.

Asteroid 2006 VV2 is classified as a Potentially Hazardous Object by Nasa because its orbit around the Sun brings it so close to the Earth. Today’s flyby will bring it to a distance of just 2.1 million miles from us. That is eight times as far as the Moon but a near miss in cosmic terms.

An asteroid the size of 2006 VV2 could blast a crater the size of London and cause devastation for hundreds of miles around. Astronomer Jay Tate, who runs the Spaceguard UK centre at Knighton, Wales, told Skymania News: “Rocks like VV2 show how essential it is to monitor our bit of space. They are a very real danger and we need to find and track them.

“Dinosaurs are extinct because they couldn’t do anything about the asteroid hazard. We are still facing precisely the same risk.”

The Nasa photo is not of VV2 but shows Gaspra, an asteroid pictured by the Galileo spaceprobe en route to Jupiter in 1991.

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