I remember reading as a kid about the Tunguska explosion in Siberia in 1908. Peasants gave vivid and sometimes exaggerated descriptions of what they experienced. One folk said he and his cattle were hurled into the air, such was the intensity of the quake that was recorded the world over in seismographs.
I was watching an episode of Carl Sagan's COSMOS a few days ago that described the Tunguska event and the possible causes behind it. Scientists have, for years, contended that the culprit behind the heavenly explosion whose earthly impact caused widespread destruction could only be a meteor or a comet. What makes it all so baffling is that no debris has ever been found in spite of numerous expeditions to the hinterland of Tunguska.
The comet hypothesis found favor amongst a majority of scientists (including Carl Sagan) in recent years. Other people have come up with more colorful ideas (like a nuclear powered alien ship meeting with an accident), most of which have been widely ridiculed and rejected by the scientific community.
Whatever be the reason behind the explosion, the enigma just refuses to die. Coincidentally, I came across this article on Yahoo! News just after completing the COSMOS episode. Old memories of reading accounts of the event came flooding in.
This video is pertinent.