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Odd Impact Crater found in the North Sea

An anonymous reader writes "Just noticed this on MSNBC. It seems they discovered an impact crater in the North Sea that doesn't look like anything else seen on Earth. Supposedly it looks like something usually seen on moons of Jupiter."

6 of 27 comments (clear)

  1. AP Story by ELCarlsson · · Score: 3, Informative

    Here's another story about it Nandotimes.com . I think that this is pretty neat. I'm glad to see how technology is able to detect stuff like this even deep under the sea.

  2. No, that's the hard way... by eyepeepackets · · Score: 4, Insightful

    ...to catch space rocks. If you let them hit the water, they splash all over everything and heat up the air. Better to catch them _before_ they enter the atmosphere.

    See, if the dinosaurs had been smarter, they wouldn't be extinct. Q.E.D.

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  3. One In A Billion by panthro · · Score: 3, Interesting

    Stewart said that if Silverpit was created 60 million years ago, there wouldn't be any cause to link the two impacts. "On the other hand, if it came out at 65 million years ago, we would have the possibility that Silverpit was in fact a fragment of Chicxulub [...]"

    IANAG(eologist). It seems to me, though, that if Silverpit was a fragment of Chicxulub, it would have to have hit the surface of the earth within a matter of hours as the part that hit near the Yucatan. They speak in the article of pinning the time frame down to 65 million years ago, and I'm assuming give or take half a million. With the information I have at hand, Chicxulub and Silverpit could have been up to a million years apart. Do you know what a million years is, in hours? About 8.76 billion. That's a pretty big margin of error! I don't think we should get our hopes up about the multi-dinosaur-killing-meteorites thing despite all its appeal, unless there is some other more substantial reason to believe these two meteorites had anything to do with one another. After all, a lot of meteorites hit the earth every million years.

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  4. What *is* odd about this is... by Randym · · Score: 4, Informative
    ...the concentric circles. Most asteroids, because of their angle of impact, leave an elliptical footprint, with a bit of a "splash" [ejecta], sometimes forming a hill or mountain beyond the impact point. Concentric circles seem to indicate a "straight-in" impact, which leads to the idea that the object was going pretty darned fast (not slowed down much by atmosphere) *and* at just the right angle to compensate for the rotational speed of the Earth.

    Concentric circles would be more common on worlds with little atmosphere to slow the object. Since we know that Earth at that time had a (relatively) thick atmosphere, it just makes the puzzle all the more interesting. What would be interesting to find out is the metal composition at the center of the impact site -- that could tell us a great deal about what hit. Probably iron, but it *could* be something as heavy as uranium.

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  5. Almost all impact craters are circular by dmatos · · Score: 3, Informative

    I remember seeing a study on this on Discovery or TLC. The fired rifle bullets into sand at high velocities and at many different angles, and the resulting crater was almost always circular. A quick google search turns up this link, a section from some lecture notes at University College Worcester.

    Craters are not always circular as they may have been created from impacts which hit the surface at oblique angles forming elliptical craters however as impact craters are formed by very high velocity impacts which act essentially like an explosion rather than a distortion of the surface so unless the impact is very shallow and ploughs along the surface the craters will tend to be circular.

    Here is another interesting quote from the same page that may explain the concentric rings:

    If the crater is larger and the same order of magnitude as the thickness of the lithosphere then shock waves will penetrate the more plastic athenosphere resulting in the formation of multiringed basins.

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  6. Map URL by ke4roh · · Score: 3, Informative

    See a map of the crater accompanying the National Geographic story.

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