Ukrainian astronomers have discovered a 410 m (1350 ft) wide asteroid passing through the constellation of Camelopardalis (the Giraffe). This chunk of rock and metal could be back in Earth’s neighbourhood in 2032. Even though there are well over 10000 other known near-Earth objects, predictably parts of the internet and media have gone nuts at the news!
The newly discovered asteroid now designated 2013 TV135 made a close flyby to Earth on 16 September 2013. “Close” means it came within about 6.7 million km (4.2 million miles) of our planet, so it missed by more than 17 times the Earth to Moon distance. It was discovered on 8 October 2013 (yes, after the flyby), by astronomers working at the Crimean Astrophysical Observatory in Ukraine.
The asteroid’s orbit is still not accurately determined but we know that roughly every three years it cycles between Earth’s orbital distance to almost three quarters of the distance to Jupiter’s orbit and back. One of these scheduled return visits has alarmed some. At the moment (and this is far from final), there is a tiny chance of a collision with Earth on 26 August 2032. “Tiny” in this context means a 1 in 63000 chance of collision (and hence a 99.998% probability it will miss) according to NASA’s Near-Earth Object Program Office. This slight risk of disaster means 2013 TV135 is now the most worrying cosmic threat to our planet, so it has been placed on the List of the Potentially Hazardous Asteroids, provoking alarmist headlines from media outlets including ABC, the Huffington Post, Novosti, Newsy, and the Examiner .
2013 TV135 has a mass of 80 billion tonnes. Where it to fall onto our world (remember, it almost certainly wouldn’t), 2013 TV135 would not quite be a dinosaur-killer but it might potentially be a civilisation-slayer. In the blink of an eye, the impact would leash destructive energy equivalent to 2500 megatonnes of TNT (to put this into perspective, between 1945 and 1996, puny humans detonated 510 megatonnes equivalent of nuclear devices).
As we observe this wandering planetoid, astronomers will refine the elements of its orbit, and most likely drastically reduce the odds of it hitting our planet.
UPDATE: As predicted by 7 November 2013 the chance of this asteroid colliding with Earth has dropped to an exceeding unlikely 1 in 169 million.
(Article by Colin Johnston, Science Communicator)