Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Space Science

Crater From 1908 Tunguska Blast Found 192

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."
This discussion has been archived. No new comments can be posted.

Crater From 1908 Tunguska Blast Found

Comments Filter:
  • by $RANDOMLUSER ( 804576 ) on Thursday November 08, 2007 @10:25AM (#21280779)
    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.
  • by AikonMGB ( 1013995 ) on Thursday November 08, 2007 @10:31AM (#21280843) Homepage

    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-

  • Tesla connection? (Score:4, Interesting)

    by sobolwolf ( 1084585 ) on Thursday November 08, 2007 @10:57AM (#21281139) Journal
    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!!!!!
  • Re:Googlink (Score:3, Interesting)

    by PhilHibbs ( 4537 ) <snarks@gmail.com> on Thursday November 08, 2007 @11:09AM (#21281279) Journal
    Whereas this [google.com] is where the BBC reported [bbc.co.uk] it was back in June.
  • by Joaz Banbeck ( 1105839 ) on Thursday November 08, 2007 @11:11AM (#21281299)
    From a 1960 interview with a witness, he refers to the existence of lake Cheko prior to the event:

    In that place the seven rich Dzhenkoul brothers in those days pastured a reindeer herd of 600-700 head. The brothers were rich. On that day, [my] father went to meet the reindeer on the Ilimpo [river] (in the north). The herd was pastured between the Kimchu river and the Polnoty (Churgim) river. On the upper reaches of the Polnoty river there was a storehouse. There was a second storehouse at the mouth of the Cheko...
    More at: http://www.vurdalak.com/tunguska/witness/dzhenkoul_l.htm [vurdalak.com]
  • Re:Airburst (Score:5, Interesting)

    by ChrisA90278 ( 905188 ) on Thursday November 08, 2007 @12:49PM (#21282543)
    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
  • by Sara Chan ( 138144 ) on Thursday November 08, 2007 @01:27PM (#21283081)
    The hypothesis that the blast was due to a comet/asteroid/etc. has been around for a long time. The problem with this hypothesis is that it does not fit at all well with the observations (e.g. the strange sounds and lights that preceded the blast for days; and so on). An alternative hypothesis was proposed by Wolfgang Kundt, a researcher at the Institut für Astrophysik der Universität Bonn:

    Kundt W. (2001),
    The 1908 Tunguska catastrophe: An alternative explanation [ernet.in]”,
    Current Science, 81: 399–407.

    Kundt's paper explains the various problems with the comet/asteroid hypothesis. It also proposes an alternative hypothesis: that Tunguska was a natural gas leak (from the ground), that went on for days, building up, until ignited by a lightning strike.

    This explanation seems to fit the observations well. Perhaps the main reason it has not gotten much attention is that it is not very exotic.
  • by iamlucky13 ( 795185 ) on Thursday November 08, 2007 @02:45PM (#21284321)

    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.

Real Programmers don't eat quiche. They eat Twinkies and Szechwan food.

Working...