Big Asteroid Less Likely to Hit Earth

This story was updated at 11:45 p.m. EDT.

The large asteroid Apophis poses less of a threat ofwalloping the Earth in the year 2036 than previously thought, new researchfinds.

The Apophisasteroid, discovered in 2004, is larger than two football fields in sizeand has captured the space rock limelight in recent years because of its potentialto hit Earth in the relatively near future.

The asteroid would not cause a global catastrophe, but couldlikely spawn significantregional devastation if it were ever to strike the planet, scientists havesaid.

Now, new data from observations made with the University of Hawaii's 88-inch telescope near the summit of Mauna Kea have allowed astronomersto recalculate the space rock's orbital path. Fortunately for us, the new path indicatesthat the asteroid is less likelyto smack Earth.

"Apophis has been one of those celestial bodies thathas captured the public's interest since it was discovered in 2004," said SteveChesley, a near-Earth object scientist at NASA's Jet Propulsion Laboratory(JPL) in Pasadena, Calif. "Updated computational techniques and newlyavailable data indicate the probability of an Earth encounter on April 13,2036, for Apophis has dropped from one-in-45,000 to about four-in-amillion."

Initially, Apophis was thought to have a 2.7 percent chanceof impactingEarth in 2029. Additional observations of the asteroid ruled out anypossibility of an impact in 2029.

However, the asteroid is expected to make a record-setting ?but harmless ? close approach to Earth on Friday, April 13, 2029, when it comesno closer than 18,300 miles above Earth's surface.

The new data shows that the asteroid will make another closeapproach with Earth in 2068 with the chance of impact currently atapproximately three-in-a-million. As with the other potential impacts, nowruled as mere close encounters, the probability of the 2069 impact is expectedto go down as more information on the asteroid is gathered.

"The refined orbital determination further reinforcesthat Apophis is an asteroid we can look to as an opportunity for excitingscience and not something that should be feared," said Don Yeomans,manager of the Near-Earth Object Program Office at JPL. "The public canfollow along as we continue to study Apophis and other near-Earth objects byvisiting us on our AsteroidWatch Web site and by following us on the@AsteroidWatch Twitter feed."

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