Comet dust from 4 billion years ago shakes up scientific world

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Date: 16 Dec 2006 05:33:50
From: Rick Evans
Subject: Comet dust from 4 billion years ago shakes up scientific world

http://www.mercurynews.com/mld/mercurynews/news/breaking_news/16242879.htm

"One of the biggest surprises is that the comet contained a mineral called
osbornite that forms at extremely high temperatures -- nearly 5,000 degrees,
and thus must have come from near the sun."
"This means that the solar system couldn't have formed as was previously
thought, from a slowly inward condensing cloud known as a solar nebula.
Because the comet formed near the cold outer edges of the solar system,
there must have been a great deal of mixing in the cloud. Material wasn't
only moving inward, some of it was also moving outward."

--
Rick Evans
----------------------------------------------------------------
Lat +42° 11' 07"
Lon -71° 04' 35"

Date: 16 Dec 2006 01:15:59
From: George
Subject: Re: Comet dust from 4 billion years ago shakes up scientific world

"Rick Evans" <dontspamme@nospam.net > wrote in message
news:2zLgh.68$uq5.44@trndny04...
> http://www.mercurynews.com/mld/mercurynews/news/breaking_news/16242879.htm
>
> "One of the biggest surprises is that the comet contained a mineral
> called osbornite that forms at extremely high temperatures -- nearly
> 5,000 degrees, and thus must have come from near the sun."
> "This means that the solar system couldn't have formed as was previously
> thought, from a slowly inward condensing cloud known as a solar nebula.
> Because the comet formed near the cold outer edges of the solar system,
> there must have been a great deal of mixing in the cloud. Material wasn't
> only moving inward, some of it was also moving outward."
>
>
> --
> Rick Evans
> ----------------------------------------------------------------
> Lat +42° 11' 07"
> Lon -71° 04' 35"
>

I've seen this story all over the place and have yet to see anyone point
out exactly what they found (mineral/organicswise). I do understand that
PAHs were among the findings (at least, if my memory serves me correctly).

George

Date: 16 Dec 2006 10:25:54
From: Mike
Subject: Re: Comet dust from 4 billion years ago shakes up scientific world

Date: 15 Dec 2006 22:43:58
From: Bill Hudson
Subject: Re: Comet dust from 4 billion years ago shakes up scientific world

Rick Evans wrote:
> http://www.mercurynews.com/mld/mercurynews/news/breaking_news/16242879.htm
>
> "One of the biggest surprises is that the comet contained a mineral called
> osbornite that forms at extremely high temperatures -- nearly 5,000 degrees,
> and thus must have come from near the sun."

Near *a* sun, not necessarily ours, unless there is something I'm
missing. This seems like a typical journalistic error: stating a
scientific conjecture as a statement of fact.

> "This means that the solar system couldn't have formed as was previously
> thought, from a slowly inward condensing cloud known as a solar nebula.
> Because the comet formed near the cold outer edges of the solar system,
> there must have been a great deal of mixing in the cloud. Material wasn't
> only moving inward, some of it was also moving outward."

Everybody knows that our solar system is a 2nd or 3rd generation system
(probably a bit of both), because of the presence of heavy elements. I
don't understand why this mineral had to have formed near *our* local
star.

Date: 16 Dec 2006 09:46:20
From: George
Subject: Re: Comet dust from 4 billion years ago shakes up scientific world

"Bill Hudson" <oldgeek61-951@yahoo.com > wrote in message
news:1166251438.556561.215860@n67g2000cwd.googlegroups.com...
>
> Rick Evans wrote:
>> http://www.mercurynews.com/mld/mercurynews/news/breaking_news/16242879.htm
>>
>> "One of the biggest surprises is that the comet contained a mineral
>> called
>> osbornite that forms at extremely high temperatures -- nearly 5,000
>> degrees,
>> and thus must have come from near the sun."
>
> Near *a* sun, not necessarily ours, unless there is something I'm
> missing. This seems like a typical journalistic error: stating a
> scientific conjecture as a statement of fact.

Osbornite has been found embedded in oldmanite in an achondrite meteorite
as well as inclusions in corundum, and in weathered detritus from a breccia
pipe cemented with an alkalic ultramafic cement. So it has been found here
on earth. Corundum forms in the upper mantle, so why couldn't the specimen
in question also have some from the formation of a rocky body, such as the
earth? Couldn't it simply be a leftover from the formation of the inner
planets?

>> "This means that the solar system couldn't have formed as was previously
>> thought, from a slowly inward condensing cloud known as a solar nebula.
>> Because the comet formed near the cold outer edges of the solar system,
>> there must have been a great deal of mixing in the cloud. Material
>> wasn't
>> only moving inward, some of it was also moving outward."
>
> Everybody knows that our solar system is a 2nd or 3rd generation system
> (probably a bit of both), because of the presence of heavy elements. I
> don't understand why this mineral had to have formed near *our* local
> star.

I think one would have to, at a minimum, determine the age of the specimen
before one could say that it came from some pre-sun star.

George

Date: 18 Dec 2006 12:45:49
From: Llanzlan Klazmon the 15th
Subject: Re: Comet dust from 4 billion years ago shakes up scientific world

"George" <george@yourservice.com > wrote in
news:tATgh.302$641.215@bignews4.bellsouth.net:

>
> "Bill Hudson" <oldgeek61-951@yahoo.com> wrote in message
> news:1166251438.556561.215860@n67g2000cwd.googlegroups.com...
>>
>> Rick Evans wrote:
>>> http://www.mercurynews.com/mld/mercurynews/news/breaking_news/16242879.
>>> htm
>>>
>>> "One of the biggest surprises is that the comet contained a mineral
>>> called
>>> osbornite that forms at extremely high temperatures -- nearly 5,000
>>> degrees,
>>> and thus must have come from near the sun."
>>
>> Near *a* sun, not necessarily ours, unless there is something I'm
>> missing. This seems like a typical journalistic error: stating a
>> scientific conjecture as a statement of fact.
>
> Osbornite has been found embedded in oldmanite in an achondrite
> meteorite as well as inclusions in corundum, and in weathered detritus
> from a breccia pipe cemented with an alkalic ultramafic cement. So it
> has been found here on earth. Corundum forms in the upper mantle, so
> why couldn't the specimen in question also have some from the formation
> of a rocky body, such as the earth? Couldn't it simply be a leftover
> from the formation of the inner planets?
>
>>> "This means that the solar system couldn't have formed as was
>>> previously thought, from a slowly inward condensing cloud known as a
>>> solar nebula. Because the comet formed near the cold outer edges of
>>> the solar system, there must have been a great deal of mixing in the
>>> cloud. Material wasn't
>>> only moving inward, some of it was also moving outward."
>>
>> Everybody knows that our solar system is a 2nd or 3rd generation system
>> (probably a bit of both), because of the presence of heavy elements. I
>> don't understand why this mineral had to have formed near *our* local
>> star.
>
> I think one would have to, at a minimum, determine the age of the
> specimen before one could say that it came from some pre-sun star.
>
> George
>
>

It is quite plausible that the Sun formed as part of a cluster so the
neighborhood was probably rather untidy at that time.

Klazmon.

Date: 18 Dec 2006 06:13:55
From: Mike
Subject: Re: Comet dust from 4 billion years ago shakes up scientific world

Date:
From: Martin Brown
Subject: Re: Comet dust from 4 billion years ago shakes up scientific world