Water on Mars

[s243a]

Depends which Mars we are talking about. I understand that a severe sandstorm, might have winds of around 400 miles an hour....now that wouldn't do anyone's eyes any good.:roll::smile:

Wear goggles. Keep in mind that the winds although faster are at a lower pressure differential. The wind is faster but blowing with a less equivalent force then a 400 mile per hour wind on earth.

 

[s243a]

I think you are right...but water does not exist in large quantities on the surface. There is a bit of water ice at the poles but that is all. "The average air pressure at the surface of Mars is 6 millibars (compared to 1013 millibars on Earth)." Any liquid water would boil away instantly.

Normal water would but if the water has enough salts in it it might not.

 

[IdRatherBeSkiing]

Normal water would but if the water has enough salts in it it might not.

The salts lower the freezing point but do they also not lower the boiling point? I remember my mom always added salt to a pan of water she was boiling for that reason. Perhaps that is just an old wives tale.

 

[#juan]

The salts lower the freezing point but do they also not lower the boiling point? I remember my mom always added salt to a pan of water she was boiling for that reason. Perhaps that is just an old wives tale.

That's funny. My Mom did that too but I have no idea why. It would definitely lower the freezing point but it wouldn't do much for the boiling point..................Did I tell you about my Mom putting a pan of boiling water out on the porch during a very cold northern B.C. Winter. It froze so fast that the ice was still warm........:lol::lol::roll:

 

[s243a]

The salts lower the freezing point but do they also not lower the boiling point? I remember my mom always added salt to a pan of water she was boiling for that reason. Perhaps that is just an old wives tale.

http://www.sci-journal.org/index.ph...2/v3n2a2.html&link=reports/home.php&c_check=1

 

[s243a]

"First of all, you have to remember that the average atmospheric pressure on Mars is very close to the triple point of water," explains Richard Hoover, an astrobiologist at the Marshall Space Flight Center. "You only have to increase the pressure a little bit to make liquid water possible."

[SIZE=-1]

[/SIZE]The 'triple point' is the combination of pressure (6.1 millibars) and temperature (0.01 °C) at which water can exist simultaneously in all three states: a solid, a liquid and a gas (see the 'phase diagram' below). On Earth, our experience with the triple point is usually limited to ice skating. The temperature of ice on a skating rink is just a fraction of a degree from the triple point. A little bit of pressure on the solid ice can cause it to transform to a liquid. The weight of a skater applied to the ice along the blade of the skate therefore creates a thin layer of liquid water that lubricates the blade and makes gliding possible.

http://science.nasa.gov/headlines/y2000/ast29jun_1m.htm

"Salts have the potential to significantly lower the freezing point of water," agrees Steve Clifford of the Lunar and Planetary Institute. "Indeed, there are some combinations of salts that can lower the freezing point by as much as 60 °C. However, thermodynamic and chemical stability arguments (arising from work by Benton Clark) suggest that, on Mars, the most potent freezing point-depressing brines are likely to be based on NaCl (common table salt)."

So salts can lower the freezing boiling and raise the boiling point. This means more opportunity for water to exist on mars even if only for a short period of time from it seeping out from the ground under pressure.

 

[#juan]

Interesting exercise...Any liquid water on Mars would likely be saturated with dissolved materials but the boiling point is likely to be more dependant on pressure than temperature.