That was close: Earth dodges death by just 600,000 miles...

For a few hours yesterday it looked as thought that 30-year mortgage might not have been such a smart buy after all, writes Charles Arthur, Science Editor. It was announced that an asteroid a mile wide was whirling towards the Earth, and there was a real chance that unless we took some avoiding action, it would hit us and wipe out civilisation.

Discovered last year, and known as 1997 XF11, the object was said to be certain to pass closer than the Moon to the Earth and astronomers even said they knew when worlds might collide: 6.30pm GMT, Thursday, 26 October 2028. But Nasa later announced that it will miss us by 600,000 miles.That is far outside the orbit of the Moon which is about 240,000 miles from Earth. But you may yet have to rethink the pension plans as by the year 2020 there will be at least 63 asteroids that will have passed within 15 million kilometres of the Earth.

An impact with an asteroid a mile across would be literally earthshaking, unleashing the energy of 100,000 hydrogen bombs, causing tidal waves, atmospheric shocks and throwing dust into the air which could induce a new Ice Age. "It would cause a global catastrophe," said Mark Bailey of the Armagh Observatory. "A quarter of the world's population could be wiped out." An asteroid four times larger almost certainly annihilated the dinosaurs 65 million years ago.

Benny Peiser, an anthropologist at Liverpool's John Moores University who has made a special study of the potential effect of asteroid impacts, said: "The Government has completely ignored the whole area and the whole subject. We need a clear research strategy and funding for a detecting system of observatories scanning the sky for these objects." Scientists will get a chance to determine whether 1997 XF11 is on a collision course in 2002, when its orbit next brings it near the Earth. If Earth does have a bullseye painted on it, then H-bombs might be its saviour. Professor Bailey explained: "The idea would be to give it a kick without blowing it into smaller pieces. You could detonate a warhead just off its surface, so it vaporises the dust layer: the jet effect would then divert it."

t Astronomers last night announced the discovery of the most distant known object in the universe - a galaxy which existed when the cosmos was only one sixteenth of its present age. Light from the galaxy 0140+326RDI has taken 12.22 billion years to reach us.