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The Tunguska Event Options
Daemon
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The Tunguska Event

In 1908, a massive aerial explosion near Siberia's Stony Tunguska River flattened 500,000 acres (2,000 sq km) of forest—felling an estimated 80 million trees over 830 sq mi (2,150 sq km) and producing a shockwave that shattered windows hundreds of miles away. Known as the Tunguska event, the explosion is thought to have measured 5.0 on the Richter scale, with an estimated energy 1,000 times more powerful than the atomic bomb dropped on Hiroshima. What do most scientists believe caused the event? More...
KSPavan
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Article of the Day
The Tunguska Event
In 1908, a massive aerial explosion near Siberia's Stony Tunguska River flattened 500,000 acres (2,000 sq km) of forest—felling an estimated 80 million trees over 830 sq mi (2,150 sq km) and producing a shockwave that shattered windows hundreds of miles away. Known as the Tunguska event, the explosion is thought to have measured 5.0 on the Richter scale, with an estimated energy 1,000 times more powerful than the atomic bomb dropped on Hiroshima.
KSPavan
Posted: Sunday, September 24, 2017 5:34:01 AM

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Article of the Day
The Tunguska Event
In 1908, a massive aerial explosion near Siberia's Stony Tunguska River flattened 500,000 acres (2,000 sq km) of forest—felling an estimated 80 million trees over 830 sq mi (2,150 sq km) and producing a shockwave that shattered windows hundreds of miles away. Known as the Tunguska event, the explosion is thought to have measured 5.0 on the Richter scale, with an estimated energy 1,000 times more powerful than the atomic bomb dropped on Hiroshima.
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Tunguska event
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Tunguska event

Tunguska event
Russia-CIA WFB Map--Tunguska.png
Location of the event in Siberia (modern map)
Event Explosion in forest area (10–15 Mtons TNT)
Time 30 June 1908
Place Podkamennaya Tunguska River in Siberia, Russian Empire
Effects Flattening 2,000 km2 (770 sq mi) of forest; seen by glowing sunsets
Damage Mostly material damages to trees
Cause Probable airburst of small asteroid or comet

The Tunguska event was an enormously powerful explosion that occurred near the Podkamennaya Tunguska River in what is now Krasnoyarsk Krai, Russia, at about 07:14 KRAT (00:14 UT) on June 30 [O.S. June 17], 1908.[1][2][3] The explosion, having the epicentre (60.886°N, 101.894°E), is believed to have been caused by the air burst of a small asteroid or comet at an altitude of 5–10 kilometres (3–6 mi) above Earth's surface. Different studies have yielded widely varying estimates of the object's size, on the order of 60 m (200 ft) to 190 m (620 ft).[4] It is the largest impact event on or near Earth in recorded history.[5]

The number of scholarly publications on the problem of the Tunguska explosion since 1908 may be estimated at about 1,000 (mainly in Russian). Many scientists have participated in Tunguska studies, the best-known of them being Leonid Kulik, Yevgeny Krinov, Kirill Florensky, Nikolai Vladimirovich Vasiliev, and Wilhelm Fast.[6] In 2013, a team of researchers led by Victor Kvasnytsya of the National Academy of Sciences of Ukraine published analysis results of micro-samples from a peat bog near the blast epicenter showing fragments possibly of meteoric origin.[7][8]

Although the asteroid or comet appears to have burst in the air rather than hitting the surface, this event still is referred to as an impact. Estimates of the energy of the blast range from 3 to as high as 30 megatons of TNT (13–130 PJ),[9][10] with 10–15 megatons of TNT (42–63 PJ) the most likely[10]—roughly equal to the United States' Castle Bravo thermonuclear bomb tested on March 1, 1954; about 1,000 times more powerful than the atomic bomb dropped on Hiroshima, Japan; and about two-fifths the power of the later Soviet Union's own Tsar Bomba (the largest nuclear weapon ever detonated).[11]

The Tunguska explosion knocked down an estimated 80 million trees over an area covering 2,150 square kilometres (830 sq mi). It is estimated that the shock wave from the blast would have measured 5.0 on the Richter scale. An explosion of this magnitude is capable of destroying a large metropolitan area.[12] This possibility has helped to spark discussion of asteroid deflection strategies.
Description
Trees knocked over by the Tunguska blast. Photograph from the Soviet Academy of Science 1927 expedition led by Leonid Kulik

At around 07:17 local time, Evenks natives and Russian settlers in the hills northwest of Lake Baikal observed a column of bluish light, nearly as bright as the Sun, moving across the sky. About 10 minutes later, there was a flash and a sound similar to artillery fire. Eyewitnesses closer to the explosion reported the sound source moving east to north. The sounds were accompanied by a shock wave that knocked people off their feet and broke windows hundreds of kilometres away. The majority of witnesses reported only the sounds and the tremors, not the sighting of the explosion. Eyewitness accounts differ as to the sequence of events and their overall duration.

The explosion registered on seismic stations across Eurasia. In some places the shock wave would have been equivalent to an earthquake of 5.0 on the Richter scale.[13] It also produced fluctuations in atmospheric pressure strong enough to be detected in Great Britain. Over the next few days, night skies in Asia and Europe were aglow;[14] it has been theorized that this was due to light passing through high-altitude ice particles formed at extremely low temperatures, a phenomenon that occurred again when space shuttles re-entered Earth's atmosphere.[15][16] In the United States, the Smithsonian Astrophysical Observatory and the Mount Wilson Observatory observed a decrease in atmospheric transparency that lasted for several months, from suspended dust.
Selected eyewitness reports
The Southern swamp—the epicentre of the Tunguska explosion, in 2008

Testimony of S. Semenov, as recorded by Leonid Kulik's expedition in 1930:[17]

At breakfast time I was sitting by the house at Vanavara Trading Post [65 kilometres/40 miles south of the explosion], facing north. [...] I suddenly saw that directly to the north, over Onkoul's Tunguska Road, the sky split in two and fire appeared high and wide over the forest [as Semenov showed, about 50 degrees up—expedition note]. The split in the sky grew larger, and the entire northern side was covered with fire. At that moment I became so hot that I couldn't bear it, as if my shirt was on fire; from the northern side, where the fire was, came strong heat. I wanted to tear off my shirt and throw it down, but then the sky shut closed, and a strong thump sounded, and I was thrown a few metres. I lost my senses for a moment, but then my wife ran out and led me to the house. After that such noise came, as if rocks were falling or cannons were firing, the earth shook, and when I was on the ground, I pressed my head down, fearing rocks would smash it. When the sky opened up, hot wind raced between the houses, like from cannons, which left traces in the ground like pathways, and it damaged some crops. Later we saw that many windows were shattered, and in the barn a part of the iron lock snapped.

Testimony of Chuchan of Shanyagir tribe, as recorded by I.M. Suslov in 1926:[18]

We had a hut by the river with my brother Chekaren. We were sleeping. Suddenly we both woke up at the same time. Somebody shoved us. We heard whistling and felt strong wind. Chekaren said, 'Can you hear all those birds flying overhead?' We were both in the hut, couldn't see what was going on outside. Suddenly, I got shoved again, this time so hard I fell into the fire. I got scared. Chekaren got scared too. We started crying out for father, mother, brother, but no one answered. There was noise beyond the hut, we could hear trees falling down. Chekaren and I got out of our sleeping bags and wanted to run out, but then the thunder struck. This was the first thunder. The Earth began to move and rock, wind hit our hut and knocked it over. My body was pushed down by sticks, but my head was in the clear. Then I saw a wonder: trees were falling, the branches were on fire, it became mighty bright, how can I say this, as if there was a second sun, my eyes were hurting, I even closed them. It was like what the Russians call lightning. And immediately there was a loud thunderclap. This was the second thunder. The morning was sunny, there were no clouds, our Sun was shining brightly as usual, and suddenly there came a second one!

Chekaren and I had some difficulty getting out from under the remains of our hut. Then we saw that above, but in a different place, there was another flash, and loud thunder came. This was the third thunder strike. Wind came again, knocked us off our feet, struck against the fallen trees.

We looked at the fallen trees, watched the tree tops get snapped off, watched the fires. Suddenly Chekaren yelled 'Look up' and pointed with his hand. I looked there and saw another flash, and it made another thunder. But the noise was less than before. This was the fourth strike, like normal thunder.
Now I remember well there was also one more thunder strike, but it was small, and somewhere far away, where the Sun goes to sleep.

Sibir newspaper, July 2, 1908:[19]

On the 17th of June, around 9 a.m. in the morning, we observed an unusual natural occurrence. In the north Karelinski village [200 verst north of Kirensk] the peasants saw to the north west, rather high above the horizon, some strangely bright (impossible to look at) bluish-white heavenly body, which for 10 minutes moved downwards. The body appeared as a "pipe", i.e., a cylinder. The sky was cloudless, only a small dark cloud was observed in the general direction of the bright body. It was hot and dr

with my pleasure
ChristopherJohnson
Posted: Sunday, September 24, 2017 1:15:00 PM

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Something exploded in the midair above the forest. The rest is obscure.
monamagda
Posted: Sunday, September 24, 2017 7:52:00 PM

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Over 100 years after the most powerful explosion in documented history, researchers are still trying to figure out exactly what happened


Over a hundred years later researchers are still asking questions about what exactly took place on that fateful day. Many are convinced that it was an asteroid or a comet that was responsible for the blast. But very few traces of this large extraterrestrial object have ever been found, opening the way for more outlandish explanations for the explosion.

The Tunguska region of Siberia is a remote place, with a dramatic climate. It has a long hostile winter and a very short summer, when the ground changes into a muddy uninhabitable swamp. This makes the area extremely hard to get to.

When the explosion happened, nobody ventured to the site to investigate. This was partly because the Russian authorities had more pressing concerns than sating scientific curiosity, says Natalia Artemieva of the Planetary Science Institute in Tucson, Arizona.

It was only a few decades later, in 1927, that a Russian team led by Leonid Kulik finally made a trip to the area. He had stumbled across a description of the event six years earlier and convinced Russian authorities that a trip would be worthwhile. When he got there, the damage was still immediately apparent, almost 20 years after the blast.

He proposed that an extraterrestrial meteor had exploded in the atmosphere.
It puzzled him that there was no impact crater, or in fact, any meteoric remnants at all. To explain this, he suggested that the swampy ground was too soft to preserve whatever hit it and that any debris from the collision had been buried.

Further analysis showed they were high in nickel, a known characteristic of meteoric rock. The meteor explanation looked correct after all – and K. Florensky, author of a 1963 report on the event, was keen to put the more fantastical theories to rest:

http://www.bbc.com/earth/story/20160706-in-siberia-in-1908-a-huge-explosion-came-out-of-nowhere
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