Artists depiction of the mysterious Tunguska event.
On June 30 1908 a massive explosion equivalent to a multi-megaton nuclear weapon exploded over Siberia. The explosion occurred somewhere between 5-10km above the ground and created a fireball that engulfed the forest destroying everything within 20km of the explosion. Some people have theorised that it may have been a black hole collapsing in on itself, or a piece of anti-matter colliding with Earth.
Most scientists agree that it was most likely a mountain sized piece of comet made up mostly of ice and rock. However due to the fact there was no crater or any remnants of the comet it lead to speculation.
Recently a scientist claimed to have identified pieces of rock that he believes is from the event. This however has not yet been confirmed or undergone any sort of official review.
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