Nature reports that the meteorite that cut across the sky near Chelyabinsk, Russia is the largest to hit Earth in over a century:
A meteor that exploded over Russia this morning was the largest recorded object to strike the Earth in more than a century, scientists say. Infrasound data collected by a network designed to watch for nuclear weapons testing suggests that today’s blast released hundreds of kilotonnes of energy. That would make it far more powerful than the nuclear weapon tested by North Korea just days ago and the largest rock crashing on the planet since a meteor broke up over Siberia’s Tunguska river in 1908.
If you want to learn a lot today, head to the Wikipedia article on the Tunguska Event. Quite comprehensive.
This Slate article discusses why we weren’t able to detect this Russian meteor.
The New York Times compiled six dashboard videos showing various viewpoints of the meteorite streaking across the sky. Worth a look.