2036 asteroid collision ‘effectively ruled out’

The possibility that a 325-metre-wide asteroid will impact Earth in 2036 has been “effectively ruled out” based on new data leading up to yesterday’s flyby, NASA scientists announced.

Asteroid Apophis was discovered on 19 June 2004. Credit: UH/IA

SYDNEY: The possibility that a 325-metre-wide asteroid will impact Earth in 2036 has been “effectively ruled out” based on new data leading up to yesterday’s flyby, NASA scientists announced.

When the asteroid, named Apophis after a demon from Egyptian mythology, was discovered in 2004, scientists estimated a 2.7% chance of impact in 2029 – the highest ever seen for an asteroid.

While the 2029 impact was soon ruled out, a small chance (one in 250,000) remained for a collision with Apophis in 2036 – until yesterday.

Impact odds less than one in a million

“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,” said Don Yeomans, manager of NASA’s Near-Earth Object Program Office, in a statement.

“Our interest in asteroid Apophis will essentially be for its scientific interest for the foreseeable future,” he said.

The scientists used updated information obtained by NASA telescopes in 2011 and 2012, as well as new data from the time leading up to Apophis’ distant Earth flyby yesterday.

Next month’s close shave

When asteroid Apophis does pass Earth again in 2029, it will be the closest flyby of an asteroid of its size, at 31,300 kilometres (19,400 miles) above Earth’s surface.

However much sooner, on February 15 this year, another smaller (45 metre-wide) asteroid, called 2012 DA14, will also pass Earth at less than 30,000 km – closer than the orbit of our geostationary satellites. 2012 DA14 will not be visible to the naked eye.

More information:
NASA Asteroid Watch