Off-list argument relisted because-- well, the content has great potential for
much wise input from other list members.

On Thu, 19 Mar 2009 20:11:45 -0700, you wrote:

>Lets back up a bit here. You know very well that my posts usually 
>argue against what we think we know. I think there is an over average 
>amount of guessing in meteoritics when compared to other Sciences. 
>There are a great deal of things that we simply have no way of knowing. 
>There is a well known photo of a meteorite sitting on Mars. We know it‘s 
>a meteorite because it looks just like they look on Earth. Why is that? 
>Do they Ablate the same while traveling through Mars‘ atmosphere? 

Answer-- no.  Mars has a much, much, much thinner atmosphere than Earth.  There
will be ablation, but not to the same degree.

>this ablation question came up was to question whether or not we know what 
>meteorites look like prior to entry into Earths atmosphere. 

Many asteroids have been imaged while in space.  Some have been studied from
close-up.  Some small ones have been photographed very near earth.  We know what
THEY look like in space, and have no reason to assume that the ones that happen
to intersect with Earth's orbit would look different from the others.  Moreover,
none of the asteroids we photograph in space have anything resembling a fusion
crust, nor do we know a mechanism by which an asteroid is space would require a
fusion crust.  Moreover, even if a meteorite HAD a crust formed over it in
space, the crust meteorites is composed of the same material of which the
meteorite is composed (or an oxidized version of same) -- material with a
melting point far below the temperature meteorites are known to experience as
they pass through the atmosphere.  Therefore, any crust formed in space would
burn off during atmospheric entry.

>I mentioned this study to point out that not all material ablates to form a 
>fusion crust that would change it’s appearance. 

That may be what you meant-- but it is NOT what you said.  You said that
ablation did not take place, which is not true.  Not only were the samples
ablated, but they were improperly placed on the heat shield so as to not be at
the maximum heat point where they were supposed to be-- ablation would have been
even higher (possibly complete) if the samples had been properly placed.  AND at
least one of the samples weren't properly assembled so as to protect the
bacterial samples on the bottom (and who knows what happened to material lost
completely):

http://www.cosis.net/abstracts/EPSC2008/00407/EPSC2008-A-00407-1.pdf


>at some point in their journey. And by the way the wind pressure while 
>traveling out to space could have done this damage to the rocks. 

No.

>We cannot assume the ablation was caused by reentry at all. 

Yes, we can.

>In fact because no black crust appeared we can say that this experiment 
>proved nothing about the actual cause of black crust at all. 

We know what causes the black crust-- melting of the meteorite's surface due to
the heat of atmospheric friction.

>Maybe if they had fusion crust prior to reentry they would have ablated less? 

No.  Because the fusion crust is made of the exact same material as the rest of
the meteorite, with the same melting point.  If anything, it would have began
ablation MORE QUICKLY because the black crust would absorb more heat.  Basic
physics.

>looked like prior to entry. I went on to point out that we have all seem
>pictures of meteors fly across the sky only to re-exit our atmosphere. 

Okay, I'll give you that one.  One of the rare meteoroids that enters the
atmosphere deep enough to start ablating but then skips back into space likely
has a fusion crust.  A fusion crust formed by Earth's atmosphere, like other
fusion crusts.

>survive while others don’t. Maybe something else gives them this tough surface 
>we call fusion crust? This is one of the questions I have . 

The fusion crust isn't tough-- it is a very thin, very fragile thing that
weathers away very quickly if the meteorite isn't found and "rescued" from the
weather.

>Another is why have we not figured out an easy way to authenticate whether 
>a rock is even from space. 

And there never will be a easy way-- if it looks like a meteorite to someone who
knows meteorites, well, then it can be tested.  But any meteorite that looks
just like an ordinary rock, in an area where you would expect to find ordinary
rocks, will sit there forever without being tested. 

>Moon rocks the only way to tell them apart is by chemical analysis. 
>So, you find a rock from the moon with no crust all scientist assume 
>it is from Earth. 

Not always true.  As Randy Korotev himself pointed out once on the list when
discussing possible lunar breccias, a lunar breccia will have random sized
pieces (some very small, some very large) that are not rounded-- terrestrial
sedementary breccias will usually have all the pieces of a similar size, with
rounded surfaces.  Look at photos of lunar breccias on google and you'll see
those features. 

>coating. If there were an easier way to tell them apart we would find them. 
>I have rocks that look just like the collections of Moon rocks but unless you 
>can find a scientist to study it , it will never be discovered. 

There is an old saying-- "if you see hoof prints, think horse, not zebra."  (Of
course, that wouldn't apply in Africa.)  You must look at mundane explainations
for something before you start looking at exotic ones.
 
>I am not trying to disprove any science I just want to wake up a few 
>scientists 
>to realize that we don’t know everything yet. 

Yes, there are countless things that are not known to science.  The temperature
at which a given mineral melts and the temperature that a meteoroid is subjected
to as it passes through the atmosphere are not among those unknowns, however.
If you have an ice cube, and you put it in a room where the temperature is 80
degrees F, that ice cube is going to melt.  If you take a rock with a melting
point of 1,000 degrees F and subject it to frictional temperatures of 3,000
degrees F, that rock is going to melt just as surely as that ice cube in a room.
There is no "ablation theory of fusion crusts" any more than there is a "melting
theory of why my ice cube is a puddle"-- it is a simple fact based on knowledge
of the materials that compose a meteorite and knowledge of how much frictional
heating a meteoroid entering the atmosphere would be subjected to.

>You have a way of pushing buttons but of coarse that is what you live for. 

For some, "pushing buttons" seems to mean "disagreeing with what you say, and
saying so."

>you live for. Isn’t it? The stuff I said about Cosmo chemistry is true but as 
>soon as a scientist publishes it the community will be up in arms. 

Again, "if you see hoof prints, think horse, not zebra"-- the chances of making
a monumental new discovery are much lower than the chances of having just
another H4-5.  If anyone involved in studying Carancas who has found
"inexplicable cosmochemistry" in it that they are "unwilling to publish", is
reading this, can't you at least mention it here?
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