[meteorite-list] Show me the Shock

[ALAN RUBIN]

It would have a cosmic-ray exposure age of 4.4 billion years. No iron
meteorite has a CRE age anywhere near that.

On Tue, Jul 25, 2023, 1:32 PM Alfredo Petrov via Meteorite-list <
meteorite-list at meteoritecentral.com> wrote:

> There could be pieces of iron from Earth's core floating around the solar
> system, left over from the collision that created the Moon. Since we have
> no direct chemical analyses of Earth core material, when an iron meteorite
> falls, how would we know whether it was originally Earth material or not?
>
> On Tue, 25 Jul 2023 at 20:57, Robert Verish via Meteorite-list <
> meteorite-list at meteoritecentral.com> wrote:
>
>> https://www.space.com/boomerang-meteorite-left-earth-and-returned
>>
>> A dark reddish-brown stone, picked up from the Sahara desert in Morocco a
>> few years ago, appears to be an Earth rock that was flung into space
>> where
>> it stayed for thousands of years before returning home ? surprisingly
>> intact.
>>
>> If scientists are right about this, the rock will officially be named the
>> first meteorite to boomerang from Earth. [Not for certain!]
>>
>> The discovery team's work was *presented*
>> (
>> https://conf.goldschmidt.info/goldschmidt/2023/meetingapp.cgi/Paper/20218
>> )
>> last week at an international geochemistry conference and has not yet been
>> published in a peer-reviewed journal.
>>
>> "I think there is no doubt that this is a meteorite," said Frank Brenker,
>> a
>> geologist at the Goethe University Frankfurt in Germany, who was not
>> involved with the new study. "It is just a matter of debate if it is
>> really
>> from Earth."  [But, still could be the other way around.]
>>
>> Early diagnostic tests show the unusual stone features the same chemical
>> composition as volcanic rocks on Earth. Interestingly, however, a few of
>> its elements seem to have been altered into lighter forms of themselves.
>> These lighter versions are known to occur only upon interacting with
>> energetic *cosmic rays* ( https://www.space.com/32644-cosmic-rays.html )
>> in space, which provided one of two key pieces of evidence
>> declaring the rock's trip beyond Earth, geologists say.
>>
>> Other pending measurements include unambiguous data about how much shock
>> from the original impact the stone absorbed. This unique signature can be
>> detected
>> in the permanently altered microstructures of the mineral crystals
>> forming the rock.
>> Estimating the meteorite's shock levels is "something that can be checked
>> or done
>> in one hour or so max, using naked eyes," Ferrière said, "thus, not
>> costly and a
>> very important observation in this case."
>>
>> ( https://cdn.mos.cms.futurecdn.net/uh7CnCZNh4MNnFY78yR2ke.jpg )
>> ______________________________________________
>> Meteorite-list mailing list
>> Meteorite-list at meteoritecentral.com
>> https://pairlist2.pair.net/mailman/listinfo/meteorite-list
>>
> ______________________________________________
> Meteorite-list mailing list
> Meteorite-list at meteoritecentral.com
> https://pairlist2.pair.net/mailman/listinfo/meteorite-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist2.pair.net/pipermail/meteorite-list/attachments/20230725/4616ec19/attachment.htm>