The Tunguska Event, a massive explosion near the Podkamennaya Tunguska River in what is now Krasnoyarsk Krai of Russia, at around 7:14 a.m.on June 30, 1908, has been the focus of much speculation in the past hundred years. Theories such as the end of the world (this was, not surprisingly, quickly dismissed due to conclusive evidence to the contrary), a natural H-bomb, a black hole, an antimatter explosion and even the crash of a UFO the size of Tokyo, have all kept the speculators busy.
However it is much more likely – and this is backed up with preliminary evidence – that the air burst of a large meteoroid or comet fragment at an altitude of 5 to 10 kilometers above the Earth’s surface was the cause.
Now, thanks to a team of international researchers from the Moscow State Lomonosov University, Italy's Bologna University and Germany's Center for Environmental Research in Leipzig investigating the Tunguska Event, another piece of evidence has been added to the jigsaw; this time, in the form of traces of acid rain in the region.
"Extremely high temperatures occurred as the meteorite entered the atmosphere, during which the oxygen in the atmosphere reacted with nitrogen causing a buildup of nitrogen oxides," one of the authors of the joint research, Natalia Kolesnikova, told RIA Novosti.
Given the time period at which the event took place, it went relatively unnoticed; this, despite the fact that the explosion was felt as far away as the UK. For any decent history buff, the impending Russian revolution, civil war and World War definitely allows for a relatively decent excuse.
Almost 20 years later, in 1927, a research team finally made their way to the remote Siberian region, led by Leonid Kulik, a leading meteorite expert at the Academy of Sciences. The team took statements from the locals in the area, and though they speculated that the explosion had been the result of a meteorite, they were unable to find a crater.
A little under 3 years later, a British astronomer suggested that the blast may have been caused by a small comet, composed specifically of ice and dust, thus leaving no recognizable trace of its presence.
One theory proposes that the Tunguska object was a fragment of Comet Encke. This ball of ice and dust is responsible for a meteor shower called the Beta Taurids, which cascade into Earth's atmosphere in late June and July - the time of the Tunguska event.
Possible the greatest factoid from the Tunguska Event however, is that if it had taken place a mere 4 hours and 47 minutes later, due to the Earth’s rotation, St. Petersburg would have been completely obliterated.
Posted by Josh Hill.
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