Some great info from Wired Science about a fairly close pass tomorrow by 2012 DA 14
A large space rock known as asteroid 2012 DA14 will be zipping by our planet on Feb. 15, coming within 28,000 km of Earth, the closest approach ever seen for an object its size. You can catch the event live using a backyard telescope or binoculars or watch it here on Wired with a collection of live feeds from around the world.
UPDATE 15-2-13 – 9.00am: Russian towns in the Urals have been hit by meteorite debris. Over 500 injuries so far reported. More here:
Asteroid 2012 DA14 has a diameter roughly equal to an Olympic-size swimming pool, 50 meters, and an estimated mass similar to the object that caused the 1908 Tunguska Event that destroyed a large swath of remote land in Russia. Thankfully, there is no chance that the asteroid will impact the Earth. It will come within 27,700 km at its closest approach, less than a tenth of the distance between the Earth and moon.
DA14 will also pass within the paths of geosynchronous satellites, which orbit at about 35,800 km