Asteroid Has Minor Chance of Hitting Earth in Century

A newasteroid tops astronomers list of those to watch, with the odds of an impactput at about 1-in-1,000 for May 4, 2102.

Theodds will likely go down or evaporate in the future when further observationsallow astronomers to refine their projections of the object's path.

Fornow, however, the asteroid known as 2004 VD17 is the only one rated as a 2 onthe Torino Scale, a zero-to-10 ranking of space-rock risk on which zero islittle or no risk.

ATorinoScale 2 ranking means the object merits attention from astronomers. It doesnot mean they are concerned. Even if the asteroid were ultimately determined tobe heading our way, there would be plenty of time to deflect it with futuretechnologies, experts say.

Therock is about three-tenths of a mile (500 meters) in diameter. Though not bigenough to cause global devastation, it could cause significant regionaldevastation were it to hit the planet.

"Fortunately,it is nearly a century before the close pass from VD17," wrote David Morrison,senior scientist for the NASA Astrobiology Institute, in his Near-Earth Object(NEO) newsletter today. "This should provide ample time to refine the orbitand, most probably, determine that the asteroid will miss the Earth."

Twoother space rocks are of significant interest to astronomers for similarreasons.

AsteroidApophis,formerly called 2004 MN4, is ranked Torino Scale 1, with impact odds of about1-in-5,000 on April 13, 2036.

Asteroid1950DA has an even greater chance of hitting Earth, but not until the year2880. That keeps it, by definition, off the Torino Scale for now.

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