http://www.bbc.com/earth/story/20160706-in-siberia-in-1908-a-huge-explosion-came-out-of-nowhere
On 30 June 1908, an explosion ripped through the air above a remote forest in Siberia, near the Podkamennaya Tunguska river.
The fireball is believed to have been 50-100m wide. It depleted 2,000 sq km of the taiga forest in the area, flattening about 80 million trees.
The earth trembled. Windows smashed in the nearest town over 35 miles (60km) away. Residents there even felt heat from the blast, and some were blown off their feet.
Fortunately, the area in which this massive explosion occurred was sparsely inhabited. There were no official reports of human casualties, though one local deer herder reportedly died after he was thrust into a tree from the blast. Hundreds of reindeer were also reduced to charred carcasses.
One eyewitness account said that “the sky was split in two, and high above the forest the whole northern part of the sky appeared covered with fire…
Full story on BBC
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