At around 7:17 on the morning of June 30, 1908, a man based at the trading post at Vanavara in Siberia is sitting on his front porch. In a moment, 40 miles from the center of an immense blast of unknown origin, he will be hurled from his chair and the heat will be so intense he will feel as though his shirt is on fire. The man at the trading post, and others in a largely uninhabited region of Siberia, near the Podkamennaya Tunguska River, are to be accidental eyewitnesses to cosmological history.
“If you want to start a conversation with anyone in the asteroid business all you have to say is Tunguska,” said Don Yeomans, manager of the Near-Earth Object Office at NASA’s Jet Propulsion Laboratory. “It is the only entry of a large meteoroid we have in the modern era with first-hand accounts.”
This digital sketch was done for a European Science and Tech magazine for an article on new developments on the mystery of the Tunguska event.
http://www.jpl.nasa.gov/news/features.cfm?feature=1769 Thanx NASA/JPL for the info. Lots more at the link. Below is another variant commissioned by Scientific American, Italy.