Posted on 08/20/2006 2:06:26 PM PDT by SunkenCiv
"Through field studies, we determined that Chicxulub has about 18,000 cubic kilometers of impact melt, approximately four times the volume of water in Lake Michigan," Pope said. "Sudbury has about 31,000 cubic kilometers of impact melt, approximately six times the volume of lakes Huron and Ontario combined, and nearly 70 percent more than the melt at Chicxulub." ...The researchers then used an analytical cratering model to examine possible causes for the huge difference in melt. According to the simulation results, the difference in melt volume could be readily explained if Chicxulub -- the impact crater that doomed the dinosaurs -- was formed by an asteroid and Sudbury was formed by a comet.
(Excerpt) Read more at spaceref.com ...
Heavenly Bodies Stir Up Routine Catastrophes
IOL | 3-18-2003 | Graeme Addison
Posted on 03/18/2003 12:33:33 PM EST by blam
http://www.freerepublic.com/focus/f-news/867877/posts
Are Cheney and Rove that Old?
Keep em comin!I enjoy your posts.Adds a lighter side to the squabbling.
Wouldn't the material being impacted have some effect on that as well? And isn't anything moving at orbital velocity going to make a pretty darned big hole anyway?
L
How great is the difference in the melting point between limestone and granite?
The difference between an asteroid and comets is that comets can have retrograde orbits (opposite of the direction of earths orbit) and thus are capable of hitting with much greater velocities.
How would these scientists know which direction the comet or asteroid was traveling? For that matter how do they know what it was that hit? Have they found fragments or something?
L
Lurker: Wouldn't the material being impacted have some effect on that as well? And isn't anything moving at orbital velocity going to make a pretty darned big hole anyway?The size of the body and its terminal velocity have the most to do with the energy delivered. A smaller factor is how strongly held together the rock(s) or ice or ice/rock lump is. Doublet craters (two or more craters of basically simultaneous origin) result from an incoming body fracturing due to having poor integrity; also atmospheric heating can play some factor, but with these velocities, less so.
Fraxinus: The difference between an asteroid and comets is that comets can have retrograde orbits (opposite of the direction of earths orbit) and thus are capable of hitting with much greater velocities.Asteroids also can have retrograde orbits. Comets have greater velocities because they are on much more elliptical orbits, so that (under Kepler's laws) they reach their greatest velocity when nearest the Sun. All bodies do that, but with comets it's much more obvious.
Fraxinus: How great is the difference in the melting point between limestone and granite?I think that's a great point. Also, the three times greater age of the crater means much less evidence around.
Lurker: How would these scientists know which direction the comet or asteroid was traveling? For that matter how do they know what it was that hit? Have they found fragments or something?They make a guess based on the shape of the crater. Impacts make very round craters regardless of their direction or how steep a trip the bolide took through the atmosphere; however, the crater will be slightly elliptical, with the elongation in line with the approach path. At that point I think it's a matter of which lip of the crater is higher, and in which direction the subterranean fractures are leaning.
Hang around in this topic, there'll be some squabbling any minute now. ;')
The Rovian Weather Machine also facilitates time travel.
I still wonder how they figure one was a comet and one was an asteroid.
L
They could easily be wrong. :') Also, the only difference between comet and asteroid is, comets are asteroids with ice on the outside. Or somethin'. ;')
Have a great evening.
L
- - The Rovian Weather Machine also facilitates time travel. - -
You know, I once knew that, but I forgot that tomorrow!
The Meteorite That Buried Michigan | The Sudbury Impact
Alexis Dahl
9.12K subscribers
190,740 views
October 1, 2021
https://www.youtube.com/watch?v=ycQexghR61w
https://search.brave.com/search?q=sudbury+crater+youtube&source=desktop
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