Re: Heat disposition in space

Thomas Barclay wrote:
> 
> I understood one of the big challenges in space
> was not cooking (due to all the heat generated
> by your crew, your equipment, your weapons,
> your drives, etc.) combined with your inability to
> radiate it effectively (I believe this has
> something to do with space being a vaccuum
> and this being a fair insulator?). Now, IIRC, the
> shuttle deals with this woe by jettisoning
> material into which it has jammed a bunch of
> heat it wants to say goodbye to (but I could be
> mistaken).

The shuttle deals with the overheating issue by leaving
open the cargo bay doors while in orbit. 

> I find the whole space is cold, space is hot thing
> interesting. In some sci-fi, you see it depicted
> as amazingly cold, in others, things boil.

Most often in sci-fi the whole "boiling" thing
is their attempt to show decompression (at least
in the sci-fi shows I've seen). 

> The
> truth is, if I've got it right, space (a vaccuum) is
> temperatureless (no matter to have a
> temperature). 

Cold is just the absence of heat. When the astronauts are in
orbit (okay, anything in Earth orbit) they suffer extreme
temperature changes as they transition from day/night night/day.
When they are in sunlight, they heat up quite quickly. When
on the night side of Earth, they cool off quite rapidly. Satellites
in orbit go through this thermal transition and suffer from it
as well. It is very stressful on the satellites (example: the
Hubble's old solar panels would flex from thermal expansion/
contractions twice in its every 96 minute orbit, and because
of this thermal heating/cooling, the solar panels would "flap"
upwards of 8 feet at the ends, which would cause the spacecraft
to suffer pointing control problems, forcing the gyros to work
overtime in order to keep the spacecraft pointed at the desired
target; the Hubble itself still suffers from the whole thermal
expansion/contraction thing, but it is nowhere near as bad now
that we have the new, shorter solar panels).

Mk

>The heat is the heat you bring
> with you or generate, and the cold is the result
> of things like your O2 being allowed to vent into
> a zero pressure.... thus sucking in heat to
> expand (endothermic?). Kind of a neat
> combination of problems, really.
> 
> Tomb
> ----------------------------------------------------
> Mr. Thomas Barclay
> Software Developer & Systems Analyst
> thomas.barclay@stargrunt.ca
> ----------------------------------------------------