Tunguska event
A meteorite hit the area. The most probable is an asteroid or comet of low density, and a diameter of between  and . The object exploded in a height of 7 to 14 km above ground; for this reason there is no impact crater. The problem with this theory is that meteorites of this type usually do not reach low levels of the atmosphere. Meteoroids, which contain more iron have a higher chance of reaching low levels of the atmosphere, but they do not cause such devastating explosions.