At 7:14 local TU 00:14, 30 June 1908, a catastrophic event occurred near the Tunguska River Podkamennaja, pulling down 60 million trees over 2150 km square.
The sound of the explosion was heard 1,000 miles away. A 500 km some witnesses claimed to have heard a muffled bang and seeing a cloud of smoke rising horizon. The shock wave was almost derailed several trains to 600 km of the Trans-Siberian Railway from the point of impact. It is estimated based on data collected that the power of the explosion was included between 10 and 15 megatons (40-60 petajoules).
The most reliable as Because of this phenomenon is the explosion of a stony asteroid about 30 meters in diameter moving at a speed of at least 15 kilometers per second. The explosion of the celestial body would take place at a height of 8 km. The resistance offered by the atmosphere may have shattered the asteroid whose kinetic energy is converted into heat energy. The resulting vaporization rocky object caused an immense shock wave that hit the ground.
Through a simulation, scientists at NASA and the University of Wisconsin, Christopher Chyba and Kevin Zahnle with Paul J. Thomas, exclude the possibility that the asteroid was kind of iron or carbonaceous. In the first case, the heavenly body would have reached the ground without shattering, in the second case, the explosion would take place too high in the atmosphere to devastate an area so vast taiga. For similar reasons and considerations about the density, the three scholars believe unlikely that the Tunguska event was generated by a comet.
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