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Astroid Day June 30  On the morning of June 30, 1*9*0*8, the largest asteroid impact in recorded history occurred in a remote part of Siberia, Russia. The explosion happened over the sparsely populated Eastern Siberian Taiga, above Siberia’s Podkamennaya Tunguska River in what is now Krasnoyarsk Krai. The blast flattened an estimated 80 million trees over an area of 830 square miles or 2,150 square km of forest. We now celebrate Asteroid Day each year on the anniversary of what is now known as the Tunguska event.  Witnesses reported seeing a fireball a bluish light, nearly as bright as the sun, moving across the sky, followed by a flash and a sound similar to artillery fire. Along with the sound was a powerful shockwave that broke windows hundreds of miles away and knocked people off their feet. The explosion in the sky was like nothing ever seen before.  Even though there was no crater found, it is still categorized as an impact event, and is believed to have been caused by an incoming asteroid (or comet), which never actually struck Earth but instead exploded in the atmosphere, causing what is known as an air burst, three to six miles (five to ten km) above Earth’s surface. Even though the asteroid didn’t hit the Earth per se, the atmospheric explosion was still enough to cause massive damage to the forest in the region. Recent research shows that the object was most likely a stony asteroid the size of a five-story building that broke apart about 15 miles (24 km) above the ground. It is estimated the asteroid entered Earth’s atmosphere traveling at a speed of about 33,500 miles (54,000 km) per hour.  Smoke trail from the Chelyabinsk meteor, February 15, 2013 The explosion released enough energy to kill reindeer and flatten trees for many miles around the blast site. At the time, it was difficult to reach this remote part of Siberia. It wasn’t until 1927 that Leonid Kulik led the first Soviet research expedition to investigate the Tunguska event. He made a initial trip to the region, interviewed local witnesses and explored the region where the trees had been felled. He became convinced that they were all turned with their roots to the center. He did not find any meteorite fragments, and he did not find a meteorite crater.  So what happened? Over the years, scientists and others concocted fabulous explanations for the Tunguska explosion. Some were pretty wild – such as the encounter of Earth with a stricken alien spacecraft, or a mini-black-hole, or a particle of antimatter. However, the truth is rather more ordinary. It is now thought that, in all likelihood, a small icy comet or stony asteroid collided with Earth’s atmosphere. If it were an asteroid, it might have been about a third as big as a football field – moving at about 10 miles (15 km) per second.  Tunguska today. |
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Tunguska event, enormous explosion that is estimated to have occurred at 7:14 am plus or minus one minute on June 30, 1908,
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Witnesses in the town of Kirensk and nearby towns at the same distance recollected the fireball flashing across the sky in the following terms: "A ball of fire...coming down obliquely. A few minutes later [we heard] separate deafening crash like peals of thunder...followed by eight loud bangs like gunshots." "A ball of fire appeared in the sky... As it approached the ground, it took on a flattened shape..." "A flying star with a fiery tail; its tail disappeared into the air."
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After this object passed across the sky, it approached the horizon where it was consistently described from this distance of 400 km, as appearing like a "pillar of fire," then replaced by "a cloud of smoke rising from the ground," or "a cloud of ash...on the horizon,"
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"From a closer distance of around 200 km, several witnesses gave a better description of the object itself. It was called diffuse bright ball two or three times larger than the sun but not as bright; the trail was a "fiery-white band."
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This event has always fascinated me because no one has ever been able to come up with a definitive answer to what caused the flattening of the forest. It is interesting to read about all the various hypotheses. Thank you for posting this Bret.
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We are headed into a couple days of rain. Right now it is 55F, calm, light rain. What the farmers need is HEAT for the crops to grow and mature.
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This event has always fascinated me because no one has ever been able to come up with a definitive answer to what caused the flattening of the forest. It is interesting to read about all the various hypotheses. Thank you for posting this Bret.
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We are headed into a couple days of rain. Right now it is 55F, calm, light rain. What the farmers need is HEAT for the crops to grow and mature.
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There's some excellent videos from current expeditions to the region. Somewhere I've seen some very old people's eyewitness accounts you might be interested in.
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