Asteroid to fly by Earth

2008-01-24 07:22

Paris - A huge asteroid will zoom past Earth next week at such a close distance that amateur astronomers should be able to spot it, specialists said on Wednesday.

Measuring between 150 and 600m across, asteroid 2007 TU24 would inflict devastating regional damage were it to hit Earth, but there is no risk of any collision, they said.

It will fly by on Tuesday, being around 534 000km from the Earth at its closest point at 08:34 GMT, according to a Near Earth Object (NEO) database compiled by the University of Pisa in Italy.

"For a brief time the asteroid will be observable in dark and clear skies with amateur telescopes of three inches (7.5cm) or larger," Nasa said on its NEO site (http://neo.jpl.nasa.gov).

2007 TU24 will make the closest approach of any known potentially hazardous asteroid of this size or larger until 2027, Nasa said, adding that objects of this size come close to Earth about every five years or so on average.

The rock was discovered only last October under a surveillance programme run by the University of Arizona.

According to the Minor Planet Centre of the Paris-based International Astronomical Union (IAU), the closest detected approach by an asteroid was on March 31 2004 by 2004 FU162, which came within 6 500kms of Earth.

The day after 2007 TU24's terrestrial flyby, asteroid 2007 WD5 is expected to come within 26 000kms of Mars, a distance that is less than a whisker in space terms.

2007 WD5 ignited a brief surge of excitement among astronomers after it was discovered in November.

Initial computations of its orbit gave a roughly 1-in-25 chance that it might whack into Mars on January 30, providing a celestial show that could be monitored by US and European scoutcraft there.

Measuring about 50m across, it would have delivered an impact equivalent to a three-megaton nuclear weapon. A rock of this size exploded over Tunguska, Siberia, in 1908, felling around 80 million trees over 2 200 square kms.

But further calculation showed that the hoped-for big splat would be a big miss.

"It's highly unlikely that it's going to hit," said NEO expert Benny Peiser of Liverpool John Moores University in northwestern England, as the odds of a collision by 2007 WD5 fell to around 0.01%, or one in 10 000.

- AFP