Happy 100th Birthday, Tunguska!

100 years ago today, a massive explosion occurred near the Tunguska River in what is now Krasnoyarsk Krai, Russia, knocking down 80 million trees over an 830 square mile area. The explosion was most likely caused by the air burst of a large meteoroid or comet fragment at an altitude of 3–6 miles above the Earth's surface. Estimates of the energy of the blast range from 5 to as high as 30 megatons of TNT, with 10–15 megatons the most likely - about 1000 times as powerful as the bomb dropped on Hiroshima and about one third the power of the Tsar Bomba, the largest nuclear weapon ever detonated. It is estimated that the earthquake from the blast would have measured 5.0 on the Richter scale, which was not yet developed at the time.

An explosion of this magnitude is capable of destroying a large metropolitan area. If the meteroid or comet had hit during the Cold War, it would probably have been mistaken for a nuclear attack, triggering mutually assured destruction - annihilation. Even if it doesn't take out a large metropolitan area, how would a Tunguska event be perceived now?

Happy Tunguska Day, y'all!