[meteorite-list] rock on the noggin story

From: Sterling K. Webb <kelly_at_meteoritecentral.com>
Date: Sun Jul 3 15:51:23 2005
Message-ID: <42C84198.5F5DF612_at_bhil.com>

Hi!


    MexicoDoug sent me off-list (very nice of him) a correction about
the notion of the silly "temperature of space" notion (see below), but I
don't mind taking my licks in public and, though I didn't ask him, I
hope he doesn't mind my quoting his very correct information to help him
spread the news far and wide.

    Quite right, space is vacuum and has no "temperature" of its own.
The ambient temperature of a metorite is determined by its distance from
the Sun, reflectivity, re-radiation, and a host of other factors, and
the "temperature of space" is a silly way to put it. I'm no better than,
say, a newspaper reporter! Groan!

    This is an interesting mental error, because I "knew" this, but the
piece of my brain that "knew" was not paying attention to the part of my
brain that was runing my mouth, either that, or my mouth was too busy
enjoying its own flapping to pay attention to my brain! Mouths will do
that, you know...

    Doug has done a lot of work on this. See:
<http://six.pairlist.net/pipermail/meteorite-list/2005-January/148342.html>

    and the two following messages. It's a three-parter.

    The only factor I see complicating the issue is a meteoroid on a
highly eccentric orbit coming in from a more distant colder region and
whether it has time to achieve equilibrium with what its temperature
would be nearer Earth. This depends on lots of things, but size and
thermal conductivity are the principal factors (I think).

    The accounts of brief frost on newly fallen stones are rare but by
knowledgeable observers, so maybe some stones are at temperatures of,
say, 260 absolute C instead of the 273 absolute C predicted. That would
be a 5% variation only, pretty good for a theoretical model, if you ask
me. Since this frost doesn't always happen, those stones are by
definition odd in some way. Nature LIKES variation.

    And maybe those frosty rocksicles are in a July Illinois cornfield
where it's 90 F with 90% humidity. There, I think 270 absolute C would
frost your rocks!

    Thanks, Doug!


Sterling K. Webb
-----------------------------------------
MexicoDoug_at_aol.com wrote:

> En un mensaje con fecha 07/03/2005 1:06:10 PM Mexico Daylight Time,
> kelly_at_bhil.com escribe:
>
> The vast majority of the mass of the "hot" rock is still at
> the ambient
> temperature of outer space, a stable 50 or 100 or 150
> degrees absolute.
>
> Hola Sterling, I don't want to be proofreading more in public... But
> this in particular is totally a bogus statement of yours above (in
> private, between you and me I say it). It demonstrates a resounding
> lack of understanding of how temperature works in space (ambient 50,
> 100, 150, no no no), with totally incorrect numbers in this case. An
> iron meteorite has a temperature of about +90 C, and a stone around 0
> C (32 F). I hope you correct it on your own, and am sorry to even
> mention it, but it is one of my very sensitive points (if not most
> sensitive) as you may have seen in the past:www.diogenite.com click
> on "meteoroid". I have been on a crusade to rid the world of the
> misinformation of this "temperature of space" false idea...Best
> wishes, Doug
Received on Sun 03 Jul 2005 03:50:48 PM PDT