21st Century Guide to the Tunguska Event, Siberia 1908, Comets, Asteroids, and Near-Earth Object Threats (CD-ROM)

This electronic book on CD-ROM presents a library of federal government documents and publications covering all aspects of the threat posed to Earth by Near-Earth Objects (NEOs), and the Tunguska event which devastated a portion of Siberia in 1908. The Tunguska Event: The biggest meteor in recorded history shot across the Tunguska River in Russia in 1908, and exploded like a nuclear bomb. The Tunguska meteor did not make an impact crater, but some of the effects of its explosion are similar to what could happen in a large meteorite impact. At seven in the morning on June 30, 1908, a blazing meteor streaked across the sky in central Russia. It sped northwest from Lake Baikal toward the trading post of Baikit in central Siberia, an area of dense forests, wide swamps, and meandering rivers. Before reaching Baikit, the meteor exploded in a gigantic column of fire near the Tunguska River (61 N, 101.5 E). The effects of the explosion were felt worldwide. Around the globe scientists wondered at the rapid changes in atmospheric pressure and unusual vibrations in the Earth. People within a thousand kilometers of the explosion saw both the meteor and the fire column. They also heard the explosion like a series of bombs. Closer to the explosion, people felt the ground rumble and shake. At about a hundred kilometers from the explosion, people, animals and houses were scorched and thrown by a hot blast of air. Only a few people were nearer to the blast, and they reported fires, houses being blown down and burnt, and reindeer being killed by falling trees. For 20 kilometers around the center of the explosion, the forest was flattened, with the downed trees pointing away from the explosion. At the center of the blown down area, tree trunks still stood, but all their limbs had been stripped off. The Tunguska meteor and explosion were widely reported in newspapers and magazines. However, there was little scientific interest until 1927, when the Russian Academy of Sciences organize