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Crater From 1908 Tunguska Blast Found

MaineCoasts writes "A team of scientists from the Marine Science Institute in Bologna claims to have found the crater left by the aerial blast of a comet or asteroid in 1908 in the Tunguska region of Siberia. The blast flattened 770 square miles (2,000 square kilometers) of forest, but to date no remains or crater have been found. This has left open the question of what kind of object made the impact. The team believes that, contrary to previous studies, nearby Lake Cheko is only one century old and 'If the body was an asteroid, a surviving fragment may be buried beneath the lake. If it was a comet, its chemical signature should be found in the deepest layers of sediments.' The team's findings are based on a 1999 expedition to Tunguska and appeared in the August issue of the journal Terra Nova."

16 of 192 comments (clear)

  1. I've always wondered by Dunbal · · Score: 5, Insightful

    I remember reading about this as a kid, probably introduced to it by Carl Sagan in his "Cosmos" series.

    At the time I wondered, after seeing all those flattened trees, how they failed to find the crater. Wouldn't it just be a case of going to several spots, drawing a parallel line to the flattened trees, then looking on a map for the point where the lines intersect? Presumably all the trees fell "away" from the blast area.

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    1. Re:I've always wondered by $RANDOMLUSER · · Score: 4, Interesting

      Canventional theory (and TFA) suggest that the explosion was an air-burst about 6 miles above the ground. So the "center" of the blast region is still pretty large.

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    2. Re:I've always wondered by eldavojohn · · Score: 5, Informative

      At the time I wondered, after seeing all those flattened trees, how they failed to find the crater. Wouldn't it just be a case of going to several spots, drawing a parallel line to the flattened trees, then looking on a map for the point where the lines intersect? Presumably all the trees fell "away" from the blast area. No, the explosion was above ground level, see our prior discussion on this.

      Also, my post on this has a link to a PDF with a sketch of the breaking apart and trajectories.

      Also, remember how long ago this happened. There was an expedition there but they didn't have the technology we did. I'm not sure if the tree patterns would help you 100 years later.
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    3. Re:I've always wondered by FredDC · · Score: 5, Insightful

      In theory yes, but you have to know that this is a very remote and large area. And they didn't have the technology we have available now.

      Right now we'd simply take some pictures with a satelite, and fly some helicopters to the impact spot. Back then they would've had to mount an expedition on foot. And that was simply not feasible.

      By the time it became possible to reach the impact site relatively easy, nature had already taken its course and finding the impact spot became impossible/very hard.

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    4. Re:I've always wondered by AikonMGB · · Score: 4, Interesting

      From what I know of the event, and as is stated in the summary, it was an aerial blast; i.e. the asteroid/comet/alien-spaceship exploded before impact. The "crater" where the remains of the $object should be found would not be directly under that explosion, as the $object would have some unknown velocity at some unknown angle.

      While the method you propose makes sense, all it really tells you is where the explosion occured, not where the remains can be found.

      Aikon-

    5. Re:I've always wondered by larpon · · Score: 5, Funny

      This picture was taken over the crater in Siberia with an onboard polaroid during the
      Apollo 11 mission...

         \ | /
        -  O  -
         / | \

      It reminds me of something...

    6. Re:I've always wondered by mikael · · Score: 4, Informative

      The trees that were directly below the air explosion were still upright. The trees at some distance were flattened. A large explosion all around Europe was heard on that night, along with a glow in the sky. But it took several months for the expedition to find out what had caused the explosion/light. By that time, the crater would have filled with water and appeared to be a lake to the expedition team.

      If it had been a loosely packed asteroid or a comet, it would have disintegrated into lots of small chunks and vaporised before reaching the ground.

      The eyewitness reports are interesting:

      "Kezhemskoe village. On the 17th an unusual atmospheric event was observed. At 7:43 the noise akin to a strong wind was heard. Immediately afterwards a horrific thump sounded, followed by an earthquake which literally shook the buildings, as if they were hit by a large log or a heavy rock. The first thump was followed by a second, and then a third.

      We have friends who own a house next to quarry. Whenever there is a major explosion there always seems to two explosions heard; the first seems to be the shockwave travelling through the ground (a large dull sound thump) while the second is the shockwave through the air which sounds like a shotgun being fired. Then there is the all clear. So maybe the lake is the crater.

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    7. Re:I've always wondered by iamlucky13 · · Score: 5, Interesting

      Also, remember how long ago this happened. There was an expedition there but they didn't have the technology we did. I'm not sure if the tree patterns would help you 100 years later.

      Yes. Something that is easy for us to forget is that they didn't have roads, or even much in the way of all terrain vehicles, much less helicopters or satellites when this occurred. Not to mention, it was largely ignored until after the revolution and WWI were both finished up with. The first aerial photographs taken of the site were taken 30 years later and still clearly showed the fall pattern, but no crater was visible.

      It's easy to look at the pictures and think you can simply follow the trees all the way to the center. Way easier said than done. First of all, the site is pretty much in the middle of nowhere. There's just a few scattered villages, no doubt with abysmal roads between each and almost nothing traversable with wheels leading anywhere else. They would have walked or ridden pack animals for the entire survey.

      It's also a huge area. 80 million trees were felled over 830 square miles. Hunters (I've done my share) and loggers are probably familiar with trying to walk through such an area. The trees may look all neatly arrayed in a photograph, as if you could step easily from one to the next or walk between them like a trail, but the truth is far different. Without the perspective benefit from being atop a hill, the fall pattern is more difficult to discern. The branches will lie tangled, blocking the path at frequent intervals. The trunks will be random distances apart, some managing to overlap nearby trunks. They often sit several feet above the ground, making it easy to fall and twist an ankle or knee, and exhausting to climb over again and again and again. Vegetation will have sprouted up in the 19 years between the fall and Kulik's arrival, leaving a tangled mess of shrubs and briers that sometimes appear deceptively solid from above and forboding from ground level. A mile per hour is a decent speed walking through such an area with several days worth of supplies on your back.

      But Kulik actually did push through to the center, and he found several trees standing upright, stripped of their branches, consistent with an airburst from above. He also found a bog he was convinced was a crater, but when he drained it there were old tree stumps at the bottom. For an impact to have formed the bog the blast would have shattered the old trees and tossed the remains out of the muddy crater.

  2. more importantly by circletimessquare · · Score: 4, Funny

    the impact site is 3.26 km wide. this corresponds to a resonance chamber for the tau muon rays we are all familiar with, with a frequency of 23.44 kHz. please adjust your tin foil hats accordingly

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  3. Airburst by wiredog · · Score: 4, Informative

    An airburst wouldn't leave a crater. Drawing lines would lead to the hypocenter, directly under the burst.

    1. Re:Airburst by ChrisA90278 · · Score: 4, Interesting

      It might have been multiple air bursts if the comet broke up first. Then you would have a fairly complex pattern. Likely not as simple as the ideal case there a point source blast all goes off at once. The chunk of ice was moving fast and exploded over a period of time. So the blast came from not a point but a few short line segments

  4. Re:I'm a bit worried by MarkGriz · · Score: 5, Funny

    "If scientists can't find a crater that's 2,000 square miles across then what chance do they have the day they lose their keys down the back of the sofa?"

    Considering YOU think that square miles are a measure of distance rather than area, and that kilometers are equivalent to miles, I'd say they have a better chance than you do.

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  5. Tesla connection? by sobolwolf · · Score: 4, Interesting
    I watched a google movie about Nikola Tesla the other night and there was speculation that the blast may have had something to do with the "death ray" that he was fooling around with at the time.

    Tesla built his "death ray" at Wardencliffe on Long Island, and it is a possible that he tested it one night in 1908. The story goes something like this. At the time, Robert Peary was trekking to the North Pole and Tesla asked him to look out for unusual activity. On the evening of 30 June 1908, Tesla aimed his death ray towards the Arctic and turned it on. Tesla then watched the newspapers and sent telegrams to Peary, but heard about nothing unusual in the Arctic.

    However, he did hear about the unexplainable event in Tunguska, and was thankful no one was killed, as it was clear to him that his death ray had overshot. He then dismantled his machine, as he felt it was too dangerous to keep it. Mad Scientists FTW!!!!!
  6. Googlink by PhilHibbs · · Score: 5, Informative

    Google map of the point that the National Geographic map link goes to

  7. Oblig Ghostbusters by Osurak · · Score: 4, Funny

    Dr Ray Stantz: Are you okay?
    Louis: Who are you guys?
    Dr Ray Stantz: We're the Ghostbusters.
    Louis: Who does your taxes?
    Dr Ray Stantz: You know, Mr. Tully, you are a most fortunate individual.
    Louis: I know!
    Dr Ray Stantz: You have been a participant in the biggest interdimensional cross rip since the Tunguska blast of 1909!
    Louis: Felt great.
    Dr. Egon Spengler: We'd like to get a sample of your brain tissue.
    Louis: Okay.

  8. Uni. Bologna homepage on Tunguska by Paul+Jakma · · Score: 5, Informative

    Uni of Bologna have a site on Tunguska, including a whole section on this new, possible crater - with pictures.

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