The 140-meter wide space rock whopper hit the headlines soon after it was discovered as its projected orbit gave it a 0.2 percent chance of giving us a very bad day in 2040. But University of Hawaii at Manoa astronomers rose to the challenge to better refine the asteroid's orbital trajectory to reveal that 2011 AG5 will miss us by 890,000 kilometers (550,000 miles) - that's over twice the Earth-moon distance.
On cosmic scales, that's close, but on mass hysteria-oh-my-gawd-it's-gonna-hit-us!-scales, we're totally safe.
University of Hawaii Institute for Astronomy (IfA) astronomers David Tholen, Richard Wainscoat and Marco Micheli gathered the new asteroid trajectory data via the 8-meter Gemini North telescope atop Mauna Kea, Hawaii, to zero in on the faint light being reflected by the asteroid on Oct. 20, 21 and 27, 2012.
These data were then given to NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif., who confirmed: "...the risk of collision in 2040 has been eliminated," says the IfA press release.
Although the newly refined trajectory is not vastly different from the approximated trajectory astronomers originally calculated for the space rock, the orbital uncertainties have been reduced by a factor of 60. Asteroid hunting astronomers can now, definitively, say that 2011 AG5 will not hit Earth in February 2040.
This result wasn't entirely unexpected. Observations in May 2012 had narrowed the uncertainty and everything was looking positive. The IfA observations finally reduced the risk to a definite zero.
Interestingly, the press release was issued yesterday, when the world was fixated on the fake Maya prophesy of the end of the world. What a coincidence...