MN4 2004 asteroid now considered safe

December 29 United States - According to NASA's Near Earth Object Program, 2004 MN4's assessed risk has been corrected downward to zero on the Torino scale. The Torino scale is the current method by which astronomers classify the likelihood of an impact with a near-Earth object.

A score of zero means that the possibility of a collision between the asteroid and Earth has been ruled out of consideration.

2004 MN4 was once tentatively estimated as having the highest potential of any asteroid to hit the Earth. Its risk was first calculated as 2 out of 10 on the Torino scale.

This rank was upgraded to Level 4 Dec. 24, giving it the highest score ever for a near-Earth asteroid. It was considered to have a 1 in 37 chance of striking the Earth.

Upon discovery of previously recorded sightings of the same asteroid, its estimated flight path was corrected and found to miss the Earth entirely, outside of the margin of error. The asteroid will, however, make one of the closest passes of Earth ever seen.

It will pass close enough to the Earth's for the planet's gravitational field to influence the asteroid's orbital pattern. However, NASA's current risk analysis for the asteroid indicates that "no subsequent Earth encounters in the 21st century are of any concern."