On this date, a large rocky asteroid or perhaps an icy comet entered the atmosphere traveling at an estimated speed of about 33,500 miles per hour and then detonated in the sky near the Podkamennaya Tunguska (Stony Tunguska) River in remote Siberia, Russia (60° 54′ 59″ N, 101° 57′ 0″ E). During its quick plunge, the 220-million-pound space asteroid/comet heated the air surrounding it to 44,500 degrees Fahrenheit. At 7:14:28 AM (local Siberia time), at a height of about 28,000 feet, the combination of pressure and heat caused the asteroid/comet to fragment and annihilate itself, producing a fireball and releasing energy equivalent to about 185 Hiroshima bombs. The aerial explosion explains why there was no impact crater – the great majority of the cosmic object was consumed in the explosion.
The massive explosion packed a wallop. The resulting seismic shockwave registered with sensitive barometers as far away as England. Dense clouds formed over the region at high altitudes which reflected sunlight from beyond the horizon. As a result, night skies glowed, and reports came in that people who lived as far away as Asia could read newspapers outdoors as late as midnight. Recent studies of so-called night-shining clouds sometimes linked to space shuttle launches suggest that it was, in fact, a comet that caused Tunguska.
Locally, hundreds of reindeer, the livelihood of local herders, were killed, but there was no direct evidence that any person perished in the blast. Locals believed the blast was a visitation by the god Ogdy, who had cursed the area by smashing trees and killing animals.
Due to the remoteness of the blast and the chaotic conditions prevailing inside Russia at the time, the first scientific expedition to the area would have to wait for 19 years. In 1921, Leonid Kulik, the chief curator for the meteorite collection of the St. Petersburg museum, led an expedition to Tunguska. But the harsh conditions of the Siberian outback thwarted his team’s attempt to reach the area of the blast. In 1927, a new expedition, again lead by Kulik, reached its goal.
This is rare, raw footage from the 1921 Tunguska expedition as well as modern day footage showing the aftermath of the huge Tunguska explosion in 1908.
While testimonials may have at first been difficult to obtain, there was plenty of evidence lying around. Eight hundred square miles of remote forest had been ripped asunder. Eighty million trees lying on their sides in a radial pattern acted as markers, pointing directly away from the blast’s hypocenter. When the team arrived at ground zero, they found the trees there standing upright – but their limbs and bark had been stripped away. They looked like a forest of telephone poles.
Such “debranching” requires fast moving shock waves that break off a tree’s branches before the branches can transfer the impact momentum to the tree’s stem. Thirty seven years after the Tunguska Event, branchless trees would be found at the site of another massive explosion – Hiroshima, Japan.
- Collins, G.S., Artemieva, N., Wünnemann, K., Bland, P.A., Reimold, W.U., and C. Koeberl (2008). “Comment article: Evidence that Lake Cheko is not an impact crater.” Terra Nova 20: 165-168.