Scientists reconstruct Russia meteor trajectory
A duo of Colombian scientists say they have reconstructed the orbit of the meteor that exploded earlier this month over聽Chelyabinsk, Russia.听
Relying on videos of the meteor from聽Chelyabinsk's Revolutionary Square聽and in the nearby city of Korkino, astronomers Jorge Zuluaga and Ignacio Ferrin at the University of Antioquia in Medellin, Colombia, triangulated the speed and position of the meteorite as it fell to Earth.
Zuluaga and聽Ferrin's聽conclusion rests on the assumptions that a 20-foot hole in the ice of聽Lake Chebarkul was caused by a fragment of the meteor, and that this fragment was traveling along the same trajectory as its parent body. Divers have yet to find a meteorite in the lake.听
The pair were inspired by blogger Stefan Geens, who analyzed video of the shadows cast by light poles in聽Revolutionary Square as the blazing meteor passed overhead. Using simple trigonometry, Geens , noticing that it squared nicely with an that just happened to have been picked up by a European weather satellite.听
In a paper ,聽Zuluaga and聽Ferrin took Geen's analysis further, using a gravitational analysis to reconstruct the path of the rock going back four years before impact. Their analysis indicates that the meteor was one of the Apollo asteroids, a class of space rocks whose elongated orbits occasionally cross that of our planet. There are about 5,200 known Apollo asteroids, the largest of them being 1866 Sisyphus, a six-mile wide rock discovered in 1972. Sisyphus is comparable in size to the impactor thought to have caused a global extinction event some 66 million years ago, ending the age of the dinosaurs.听
In an effort to prevent a repeat of this sort of event, European Space Agency officials announced a plan to smash a spacecraft into an Apollo asteroid聽in 2022聽to alter its orbit, just for practice. The target of the joint European/US Asteroid Impact and Deflection Assessment mission, a rock named聽65803 Didymos, poses no threat to our planet in the聽foreseeable聽future, unless of course the mission goes seriously wrong and Didymos is knocked into our path.听聽
