Posted on 03/09/2005 10:19:19 AM PST by ZGuy
It's a mystery that has puzzled scientists for years but researchers said Wednesday they have discovered why there isn't much melted rock at the famous Meteor Crater in northern Arizona.
An iron meteorite traveling up to 12 miles per second was thought to have blasted out the huge hole measuring three-quarters of a mile across in the desert.
The impact of an object at that speed should have left large volumes of melted rock at the site. But British and American scientists said the reason it didn't was because the meteorite was traveling slower than previously estimated.
"We conclude that the fragmented iron projectile probably struck the surface at a velocity of about 12 km (7.5 miles) (per second)," said Professor H. Jay Melosh, of the University of Arizona, in a report in the science journal Nature.
Meteor Crater, which was formed about 50,000 years ago, was the first terrestrial crater identified as a meteorite impact scar.
Melosh and Gareth Collins, of Imperial College London, used a simple model to calculate the speed on impact. They showed the meteorite had slowed when it hit the Earth's atmosphere and broke into fragments before it struck the Earth.
They calculated the impact velocity was about 26,800 miles per hour.
"Even though iron is very strong, the meteorite had probably been cracked from collisions in space," Melosh said in a statement.
"The weakened pieces began to come apart and shower down from about 8.5 miles high. As they came apart, atmospheric drag slowed them down, increasing the forces that crushed them so that they crumbled and slowed more," he added.
The scientists said that at about 3 miles altitude, most of the meteorite was spread in a large cloud.
It's pretty much in the middle of no where, but if you can get to see it, it's quite something.
You can look off to the south from the major highway going by it, and see a bowl shaped 'mountain' off in the distance. I've driven the way several times, quite amazing.
Only went over to look into it once. Awesome crater.
He ran the earth right into that asteroid.
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Sorry, but even at 7.5 miles/second, it came and went in the blink of an eye. And it was before my time.
View from 27,000 feet.
LOL!
I get my kicks on Route 66. I thought the mystery was the old "Spanish Mission" building along old Route 66 (current I-44, iirc) about a mile north of the crater.
Seems some conman ran a gas station from the "Spanish Mission". He had an observation tower about 25' high, from which he claimed you could see into the crater. (You couldn't). Since the human capacity for self deception is almost unlimited, most people managed to convince themselves that they had "seen the crater" and went on.
If the mark complained, he would tell them to take their ticket to the privately run (and for profit) meteor museum and they could look from there. Of course the museum did not honor his tickets, again many folks would chalk it up to experience and move on. If they returned and demanded a refund, he would grant it, out nothing but the cost of a cheap ticket.
Agreed. Only went to it once, thirty-odd years back, but the impression it left in my mind is still fresh.
But then. most of Arizona (that I've seen, anyway) is pretty amazing.
Location?
Now at least I can finally get some sleep.
Liberals would have put the earth in a lock box to protect it.
What makes them think it was 50,000 years ago?
And are there any?
Before or after the main impact site? Any astrophysicist(s) out there that can enighten me?
I actually have to say I was pretty dissappointed to pay the rather high admission price and see little more than an unimpressive hole in the ground. The idea of seeing where a meteor struck the Earth is more exciting that the actual thing. Perhaps because I'd been at the Grand Canyon (for free) the previous day, this thing didn't seem worth the detour off the freeway. If you've seen the pictures above in this thread, you've pretty much seen all you need to see.
Okay. I'm a bit slow.
If what they say in this sentence is the case.....why is there a hole? That is deeper in the middle...?
The cloud made the hole, I suppose..........? Just asking...
It's not far from Flagstaff, where you can visit the Lowell Observatory (they have public tours), a couple of hours from the ever-popular south rim of the Grand Canyon, and not far from Sedona and many interesting Indian ruins (Montezuma's Well, Montezuma's Castle). GREAT vacation spot, if you can't make it to New England.
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