[meteorite-list] Meteorite from Jupiter-- uh, I mean TO Jupiter

[Chris Peterson]

Agreed, this fact alone isn't enough to completely close the case. But 
nearly so.

Most of the heat of ablation is carried away from the meteoroid. A tiny 
stone will most likely have fragmented from a much larger one, and will have 
only undergone ablation for a fraction of a second (otherwise it would burn 
up completely). There simply isn't time to pump much heat into the interior. 
On the other hand, the small stone, with its high surface area to volume 
ratio, is subject to significant convective cooling during the several 
minutes it is falling through -40°C air at ~100 m/s. I think it is highly 
unlikely that such a small stone would arrive at the ground with a 
temperature significantly different from ambient, and most likely a bit 
below.

Convective coupling is usually going to be a more significant factor in 
determining meteorite temperature than ablative heating (treating both as 
differentials from the original temperature of the object in space).

Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com


----- Original Message ----- 
From: "stan ." <laser_maniac at hotmail.com>
To: <markf at ssl.gb.com>; <meteorite-list at meteoritecentral.com>
Sent: Wednesday, June 21, 2006 10:38 AM
Subject: RE: [meteorite-list] Meteorite from Jupiter-- uh, I mean TO Jupiter


>>Hmmm Case closed I'd say ......
>
> i wouldbnt be so quick to judge based on this fact alone. the pic of the 
> stone shows a very tiny specimin, maybe 50g tops. the smaller the rock the 
> higher the surface area to weight ratio, meaning there is less cold soaked 
> mass to absorb the heat of ablation. while i would easily belive a 5 ton 
> iron would land cold (even freezing) to the touch, i would similarly 
> belive a tiny stone could get warm to the touch.