in the morning of 30 June 1908, a few native peoples in Siberia reported seeing a blue light in the sky that was as bright as the sun and hearing a series of loud explosions, accompanied by fierce winds and fire. These explosions, which flattened the pristine Siberian Taiga for 770 miles (2,000 kilometers) around, are estimated to have had the power of 2000 Hiroshima atomic bombs. However, this area is so remote and Russia was experiencing so much political turmoil that no one was able to investigate the scene until 1927
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Gasperini’s team says their data suggest that a 10 meter (33 foot) wide fragment of the celestial object was blasted free by the explosion and continued traveling in the same direction that the original object was moving in. This fragment traveled slowly, about 1 kilometer a second (0.6 mile) per second. When the fragment plowed into the marshy terrain five miles north of the explosion epicenter, it created a long, trenchlike depression.

“It splashed on the soft, swampy soil and melted the underlying permafrost layer, releasing CO2 [carbon dioxide], water vapor, and methane that broadened the hole, hence the shape and size of the basin, unusual for an impact crater,” argues Gasperini, adding that “our hypothesis is the only one that accounts for the funnel-like morphology of Lake Cheko’s bottom.”