[Jack Hughett]

Originally Posted by CraigD

Correct. Very big meteorites essentially ignore the atmosphere. They don’t ignore the ground, however, so the ultimate effect is the same – kinetic energy converted into heat several times greater than needed to boil/vaporize the entire meteorite, with the excess vaporizing the Earth in the area of the strike.

Hey CraigD,
Is it possible that in the case of a large iron meteorite that maybe even the mass of the ground isn't enough to vaporize the object. I have even wondered if one could possibly penetrate the crust and on into the mantle. The average thickness of the crust ranges only between 20 and 120 km. An iron meteorite could penetrate this in a matter of seconds. So instead of always being splattered by impacts the earth simply swallows them up.

I personally feel that the only way to get a center peak in a crater is from ground penetration.

Jack

[TheBigDog]

Your logic is flawless, Craig, but I wonder about taking such an empirical approach. Note the thread on hot water freezing faster than cold water, could there be counterintuitive elements at play with regard to the melting and explosion of objects entering the atmosphere?

Bill

[Michaelangelica]

Earth Scars - Interactive Map - National Geographic Magazine

[bigfatpothead]

I am sorry I missed most of this as it was happening!
I have been on the road doing comedy for a bit and was pleasantly surprised that someone is with me on this, even though it's reverse of what I theorized it is nonetheless acceptable to me.

One thing I want some physics guy to answer is why are the valley edges so perfectly serated, with equidistant spacing between identical serations.
It looks like something sharp, jagged and round, rolled through the valley, zoom in on the valley and follow it from the impact point in a north east direction and count the serations, you will see the symmetry, zoom way in and you can see a cemetary!


Bigfatpothead
DOT COM

Originally Posted by Jack Hughett

Hey again Modest,

Off subject but my son claims he's the king of modesty.


"However, you're looking at this a bit backwards I think."

The story of my life!

By the way that is a fun program for figuring impacts, but it seems to be designed strictly for circular impacts. Once you get below 45 degrees the dynamics doesn't change. It maintains that the impact is circular in shape, or did I miss something in the calculation?

As far as finding shocked quartz and spherules. They may be extremely hard to find and is it possible that they may not even exist with this impact. The dynamics would be totally different from what we think of a "normal" impact.
With this (ok I'll use it) "alleged" impact zone being over 100 miles long, and the first point of contact with the earth being considered more of a grazing instead of a direct strike, would the pressures be the same?

Jack

[Turtle]

Originally Posted by bigfatpothead

I am sorry I missed most of this as it was happening!
I have been on the road doing comedy for a bit and was pleasantly surprised that someone is with me on this, even though it's reverse of what I theorized it is nonetheless acceptable to me.

One thing I want some physics guy to answer is why are the valley edges so perfectly serated, with equidistant spacing between identical serations.
It looks like something sharp, jagged and round, rolled through the valley, zoom in on the valley and follow it from the impact point in a north east direction and count the serations, you will see the symmetry, zoom way in and you can see a cemetery!


Bigfatpothead
DOT COM

The forms result from erosion and if you measure them accurately they are not equidistant. Again, (and again, and again...) no colliding space-rock 'rolls' or 'scrapes' on that scale. Put that idea to rest in that cemetary.

[charles brough]

I saw a NOVA science program a year or two ago about the comet that hit Siberia. One important point in the program was that it came in at a sharp angle. They could tell from the different directions the burned trees had been flattened down.

I tried to see the links, but none of them came up, so I have no picture of this much more immense event. I assume it was hundreds of millions of years ago if a reality.

[modest]

It was the:

Tunguska event - Wikipedia, the free encyclopedia

~modest