From the ArcaMax Publishing, Science & Technology Newsletter:
http://www.arcamax.com/news/technology/s-625805-497191
PASADENA, Calif. (UPI) -- NASA scientists say they have recalculated
the path of a large asteroid and found a significantly reduced
likelihood of an encounter with Earth in 2036.
The space agency said the Apophis asteroid is approximately the size
of 2 1/2 football fields.
"Apophis has been one of those celestial bodies that has captured the
public's interest since it was discovered in 2004," said NASA
scientist Steve Chesley. "Updated computational techniques and newly
available 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-a million."
A majority of the data came from observations made by Dave Tholen and
collaborators at the University of Hawaii's Institute for Astronomy in
Manoa. Tholen made improved measurements of the asteroid's position,
enabling him to provide NASA with new data sets more precise than
previous measures for Apophis, officials said
Among the findings is another close encounter by the asteroid with
Earth in 2068, with chance of impact currently at approximately
three-in-a-million.
Chesley and NASA scientist Paul Chodas are to present their updated
findings Thursday in Puerto Rico during a meeting of the American
Astronomical Society's Division for Planetary Sciences.