Re: (TFT) Mars - Water is cold

[Rick Smith <rsmith@lightspeed.ca>]

Sorry for the late reply.

A number of people have said that Mars' atmosphere
is a 'high grade laboratory vacuum' and that water
would boil furiously at its summer standard 
temperature and pressure.

This is wrong.  Mars has from 0.6 to 1.2% of Earth's
atmospheric pressure.  That is far from a 'high grade..'
etc.  Second, water on Mars would not boil furiously,
it is too cold.  In the highlands it will evaporate,
in the low lands water is stable.  However, the air
is DRY.  So any sort of wind will eventually evaporate 
any surface water.  

Also brines are completely stable on Mars during
summer daytime temperatures.  Salts lower the melting
point, pushing liquid brines away from the triple 
point of water.  (So rather than the temperature and 
pressure allowing ice, water and vapor to be stable, 
we would just have liquid and vapor being in 
equilibrium.)

Anyway the new NASA images that people are talking
about are pretty much a smoking gun that ground 
water, broke out from a cliff, ran for a distance
down hill and soaked into sand and evaporated.  Or
to be precise, it was likely brines that did so.

Warm regards, Rick.


On Fri, 2011-12-08 at 00:32 -0700, Jay Carlisle wrote:
> http://www.telegraph.co.uk/science/space/8682794/Water-could-be-present-on-Mars.html
> 
> I seem to be seeing "flows" of water.
> Why?
> In a low density atmosphere is the movement of frozen vapor on the surface
> enough for these images?
> This looks like more volume to me than can be accounted for via the blowing
> around of winter frosts... but I'm not a good judge of such things.
> ...
=====
Post to the entire list by writing to tft@brainiac.com.
Unsubscribe by mailing to majordomo@brainiac.com with the message body
"unsubscribe tft"