A SMALLISH asteroid missed the Earth by a whisker last weekend, sailing past the planet just 104 000 kilometres away, little more than a quarter of the distance to the Moon.
Astronomers at the University of Arizona who detected the asteroid say it was between 6 and 13 metres across. If it had plunged into the Earth's atmosphere, the chances are that it would have burned up before striking the ground, says James Scotti. In fact, as many as 10 rocky asteroids this size are probably incinerated in the Earth's atmosphere each year, he says.
If the asteroid was made of nickel and iron, however, the story could be very different. Metal asteroids do not burn up but carry on until they hit the ground, he says. About 1 per cent of asteroids are believed to be nickel-iron.
The astronomers detected the asteroid - given the seasonal name of 1994 ...
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