[meteorite-list] Meteoroid Temperature-Pretty Graph

[MexicoDoug at aol.com]

Hola Lists (and especially Lars who I hope is  feeling somewhat better in the 
wake of the storm in the State of  Denmark),

http://www.diogenite.com
then click on "Meteoroid" on the  left.

Last night I put together a simple graph of Meteoroid temperatures  for 
Ordinary Chondrites, Carbonaceous Cs, and Iron-Nickel as well.  Just  pick your 
distance from the Sun and read the outer space temperature of your  meteoroid 
anywhere up to around 0.79 light years (50,000 AU) from the  Sun...though 
materials tend to behave differently as they approach absolute zero  and molecular 
rotational and vibrational motion -which drives temperature-  approaches a 
standstill.  Ceres is at 2.8 AU on average, by the way.   Vesta a little closer 
(average 2.4 AU).  

The graph on the webpage  covers everything from Mercury to Jupiter 
distances.  

And if that's  not enough, you can download the workbook (MS Excel) and look 
at similar bright  graphs fof up to Pluto and then as a special bonus another 
one with a log  distance axis to reach the Oort Cloud.  One can see it is 
about two degrees  above absolute zero out there if you are a surprising Iron way 
out there, but  only one degree abouve absolute zero (0 = -273 C)if you are 
just a good ol'  ordinary chondrite or carbonaceously cruising.  

It is interesting  to note that if you are an Iron orbiting Earth, you are 
not cold.  You are  near the boiling temperature of water!  And ordinary 
chondrites are a  little below freezing!  It makes a big difference what group you  
are!!!  Iron meteorites are hot to start with upon entry !  Of course  all bets 
are off of the meteoroid is being eclipsed by Earth's shadow.   Then it is 
much colder than frigid if it has any time to equilibrate at  
all.......brrrrrr!!!!  So a night time meteor probably starts out frigid  with a capital F, 
though larger meteorite producing bolides at thousands of  kilometers per hour 
probably aren't too much affected before friction takes  over.  The assumption in 
the model fails that radiative equilibrium is  reached during an eclipse.  
But this is an important consideration I think  - a night time fall and a day 
time fall potentially can have very different  inicial temperatures:)

Saludos, Doug
Assumptions on Meteorite List  January  7:
http://six.pairlist.net/pipermail/meteorite-list/2005-January/148342.html
http://six.pairlist.net/pipermail/meteorite-list/2005-January/148343.html
http://six.pairlist.net/pipermail/meteorite-list/2005-January/148344.html