NASA rules out apocalypse in 2036

Yesterday, NASA announced the latest orbital data on the asteroid Apophis, which indicated that there is less than a one-in-a-million chance of it hitting Earth in 2036. As far as the space agency is concerned, that's enough to declare our planet safe from a punishing impact.

Apophis has been catching headlines since it was first discovered in 2004. At 325m in diameter and an estimated mass of 27 billion kilograms, the asteroid could cause quite a mess if it were to strike Earth. And initial calculations suggested it had over a two percent chance of doing exactly that in 2029. Further refinements in its orbit quickly eliminated that chance, but it set up an alternate possibility: the gravitational interactions during its 2029 flyby could set the object up to slam into Earth in 2036.

The new orbital information, gathered by three different observatories, effectively rule that out. The 2029 flyby will still be dramatic, as Apophis will slide past Earth at a distance of about 30,000km. That will be the closest passage of a body this size that we've ever directly observed.

NASA's announcement noted that there will be an even closer passage of a smaller asteroid next month. 2012 DA14, which is "only" 40m in diameter, will come within a bit over 27,000km when it travels past the Earth. For context, the Moon is 384,000 kilometers away.