Tunguska Event

Definition

Astronomy

  • Impact of some astronomical object, probably an asteroid or the head of a small comet, at Tunguksa in Siberia on 30 June 1908. The impact, involving an incoming mass of about 100,000 tonnes, has been thought not to have involved a solid body because it caused a large atmospheric disturbance detectable all around the world and much surface damage, including perhaps 2000 square kilometres of demolished trees, but left no impact crater. But tree resin in the area has been found to contain solid particles whose composition is close to that of stony meteorites, encouraging the asteroid theory rather than the initial notion that Tunguska was struck by the head of a comet.
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