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Russian Meteor Likely an Apollo Asteroid Chunk
astroengine writes "Helped by the extensive coverage of eyewitness cameras, CCTV footage and a fortuitous observation made by the Meteosat-9 weather satellite, Jorge Zuluaga and Ignacio Ferrin of the University of Antioquia in Medellin, Colombia, have been able to reconstruct the most likely orbit of the meteoroid that slammed into the atmosphere over the Russian Urals region on Feb. 15. What's more, they know what type of space rock it was — the Chelyabinsk-bound meteoroid originated from an Apollo-class asteroid (PDF). Apollo asteroids are well-known near-Earth asteroids that cross the orbit of Earth. Around 5,200 Apollo asteroids are currently known, the largest being 1866 Sisyphus — a 10 kilometer-wide monster that was discovered in 1972."
http://en.wikipedia.org/wiki/List_of_Apollo_asteroids
You're thinking comets, like C/2013 A1. Asteroids are numbered in order of discovery. Ceres was 1st, Pallas was 2nd. This one was 1866th.
Science is all about firing a drunk pig out of a cannon just to see what happens.
There are only 2 types of Earth crossing asteroids: Apollos with a semi major axis larger than 1AU and perihelion smaller than Earth's aphelion and Atens with a semi major axis smaller than 1AU and aphelion larger than Earth's perihelion. There are 4803 known Apollo asteroids (I don't know where the 5200 number in the summary comes from but IAU's Minor Planet Center knows of only 4803) and 747 known Atens, so there was a very good chance that the meteorite was an Apollo...