Two notes: Commenting on the blog will be turned off after 14:00 UT today for a major blog upgrade. Also, an article is in USA Today, um, today, about the topic of this post, and I'm quoted in it.
100 years ago today, a small chunk of rock or possibly ice was lazily making its way across the inner solar system when a large, blue-green planet got in its way. Traveling roughly westward, it entered the Earth's atmosphere moving at tens of thousands kilometers per hour. Compressed and battered by tremendous forces, the object got about 5 - 10 kilometers from the ground before it succumbed, exploding like a gigantic multi-megaton bomb. The air blast flattened trees for hundreds of square kilometers. The ground shook, witnesses felt the hellish heat from kilometers away, and the shock wave circled the world. It happened over the remote Podkammenaya Tungus river, a swampy ...