[meteorite-list] Chicxulub Asteroid
From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Tue, 15 Sep 2009 16:52:00 -0500 Message-ID: <BDA55209723140C6B4E2D8BF2CDE6459_at_ATARIENGINE2> Hi, Carl, List, Two impactors of identical mass (not size, because density varies, but mass), hitting with identical speeds and at identical angles produce virtually identical craters. All that matters (if the object is bigger than 20-50 meters is kinetic energy. It could be iron, it could be rock, it could be ice, it could be highly compressed chicken feathers or a ball of fossilized fast food --- all would have the same result. A porous carboneaous chondrite of 10 km diameter and an iron ball of 5.85 km, weigh the same, and at 20 km/s and a 60-degree angle, both will produce a 65 mile crater 3/4 of a mile deep. There are high-iridium iron meteorites as well as stony ones, but an iron impact will leave other traces not found around Chicxulub. Now... the fun part! What WOULD go right through the Earth?! It would have to be very dense so that its area was very small for its huge mass. Number one best candidate is a small fast black hole. I specify "fast" because if it was slow-moving, it might slow enough to stop inside the Earth or start orbiting around inside the planet, madly eating up mantle and core material as it went until... Wow! makes me want to drag that heavy John Wheeler book off the top shelf and start scribbling. Given a black-hole of minimum mass and size m-sub-bh <<<< m-sub-earth, how long would it take to eat the entire Earth? Well, even without numbers, one can see that initially the mass consumption of the small black hole would be very modest, but as it grew and grew, the rate would increase by a power curve following the exponent of the ratio of black hole surface to black hole mass until the black hole reached a certain fraction of the Earth's mass and then a destructive deformation would occur in a catastrophic fashion... It could take thousands of years. There could be one there now. (Not true; we would hear it.) But if it was a FAST black hole, it would go straight through the Earth with only the equivalent of a black hole burp and perhaps produce a massive episode of basalt flood vulcanism as it exited. Silly notion. We don't have massive basalt flood vulcanism... What's that? We do? Every how often? Hmm. You don't suppose...? Sterling K. Webb ------------------------------------------------------------ ----- Original Message ----- From: "Carl 's" <carloselguapo1 at hotmail.com> To: <meteorite-list at meteoritecentral.com> Sent: Tuesday, September 15, 2009 4:06 PM Subject: [meteorite-list] Chicxulub Asteroid > > > > Hello, > > I've had some kids ask me some questions concerning the meteorite that > created the Chicxulub crater. I wasn't sure, so I thought I'd ask the > list. Questions have been condensed by me. > > !. Since there are high levels of iridium, is it safe to assume it was > a stony asteroid or comet but not an iron? > > 2. If it was an iron asteroid, since it was the size of Mount Everest > and going at near cosmic speed, would it have gone thru the Earth? > > Thanks. Carl, still very embarrassed! > > _________________________________________________________________ > Bing brings you health info from trusted sources. > http://www.bing.com/search?q=pet+allergy&form=MHEINA&publ=WLHMTAG&crea=TXT_MHEINA_Health_Health_PetAllergy_1x1 > ______________________________________________ > http://www.meteoritecentral.com > Meteorite-list mailing list > Meteorite-list at meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Tue 15 Sep 2009 05:52:00 PM PDT |
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