Asteroid Apophis won't hit Earth in 2036: NASA

Data discovered during a search of old astronomical images provided additional information required to rule out the 2029 impact scenario, but a remote possibility of one in 2036 remained, according to a National Aeronautics and Space Administration (NASA) statement.

Discovered in 2004, the asteroid - as big as three-and-a-half soccer fields - caught the immediate attention of space scientists and the media when initial calculations of its orbit indicated a 2.7 percent possibility of an earth impact during a close flyby in 2029.

"With new data provided by the Magdalena Ridge (New Mexico Institute of Mining and Technology) and the Pan-STARRS (University of Hawaii) optical observatories along with very recent data from the Goldstone Solar System Radar, we have effectively ruled out the possibility of an earth impact by Apophis in 2036," said Don Yeomans, manager of NASA's Near-Earth Object Program Office at the Jet Propulsion Lab in Pasadena, California.

"The impact odds as they stand now are less than one in a million, which makes us comfortable saying we can effectively rule out an earth impact in 2036. Our interest in asteroid Apophis will essentially be scientific," added Yeomans.

On April 13, 2036, a flyby of Apophis will become the closest flyby of an asteroid of its size when it comes no closer than 31,300 km to the earth's surface.

"But much sooner a closer approach by a lesser-known asteroid is going to occur in the middle of next month when a 40-metre asteroid, 2012 DA14, flies safely past the earth's surface at about 17,200 miles," Yeomans said.

"With new telescopes coming online, the upgrade of existing telescopes and the continued refinement of our orbital determination process, there's never a dull moment working on near-earth objects," added Yeomans.

NASA detects and tracks asteroids and comets passing close to earth using ground and space-based telescopes.