Space rock on way, but don't panic yet

From theage.com.au
by Daniel Dasey

SCIENTISTS have identified an asteroid that has a faint chance of ploughing into the Earth, leaving a two-kilometre-wide crater and wiping out life for 6000 square kilometres.

The asteroid measures 130 metres across and is travelling at 70,000 km/h. It would cause huge devastation if it hit the planet.

Called 2007 VK184, the space rock is 90 million kilometres from Earth and could hit in 2048. It has earned a rare hazard rating of "one" on the Torino scale, the international barometer of space object impact risk.

But while asteroid experts last week warned of the tremendous damage such a collision would cause, they were hopeful the risk of impact would diminish as more was discovered about VK184's path.

"The chances are that the probability (of an impact) will come back down to close to zero," said astronomer Gordon Garradd, who has identified numerous asteroids and works at the Siding Springs telescope in Coonabarabran, 450 kilometres north-west of Sydney.

He said VK184 had been observed for only 35 days and, given its distance from Earth and the long time until a possible impact, more readings were necessary to determine if a collision was a possibility.

NASA's Near Earth Object Program website says VK184 is travelling at 19 kilometres a second. It has a 1-in-3030 chance of hitting the planet in 2048.

The object's Torino scale rating of one (out of a possible 10) signifies it has a tiny chance of collision with Earth and that there is no cause for public concern. Every other known object that will approach Earth this century has a zero rating.

If the object struck Earth it would be up to three times worse than the asteroid that hit Russia in 1908.