<p>Any ice that forms from water will be free of salt -- the process of crystallization does an excellent job of removing impurities.</p>

<p><em>But</em> that's only when freezing out of liquid water, which is not a process that happens today at the Martian surface. When ice forms out of the air, it forms as tiny crystals -- "hoar frost" we call it on Earth -- and forms <em>on</em> substrates, such as grains of sand.  Since the soil of Mars is laden with salts of various sorts (including things a lot nastier than NaCl, such as perchlorate salts), it's hard to believe that the Martian hoar frost wouldn't be contaminated with salty sand and dust.</p>

<p>And, of course, the Martian atmosphere has dust suspended in it which is continually precipitating out and dust which is blown up by the not-infrequent dust storms and dust devils and all of this falls on any newly-formed frost.</p>

<p>It's very hard to see how there could be any macroscopic ice deposits on Mars that don't have dust and salt as impurities.</p>

CC BY-SA 4.0
2019-01-31T16:11:45.920Z
https://en.wikipedia.org/wiki/Brine_rejection
Muze
CC BY-SA 4.0
2019-01-27T20:02:41.847Z
2019-01-27T20:02:41.847Z
Mark Olson
<p>Does water on Mars form from the atmosphere as ice free from salt?
Does water desalinize through the evaporation and transpiration?</p>

<p>When the fresh top ice is placed in a container then pressurized to melt, would the water be carbonated?</p>

<p>Particulates of salt and dust is less in the atmosphere during a Martian winter so would the ice that forms be also drinkably cleaner?</p>

<p><a href="https://space.stackexchange.com/questions/33884/how-to-drink-water-on-mars">https://space.stackexchange.com/questions/33884/how-to-drink-water-on-mars</a>
<a href="https://earthscience.stackexchange.com/questions/16076/how-salty-can-ice-be">https://earthscience.stackexchange.com/questions/16076/how-salty-can-ice-be</a></p>

<p><a href="https://i.sstatic.net/gwI9m.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/gwI9m.jpg" alt="enter image description here"></a>
<a href="https://kottke.org/18/12/a-massive-ice-filled-crater-on-mars" rel="nofollow noreferrer">https://kottke.org/18/12/a-massive-ice-filled-crater-on-mars</a></p>

<mars><water><weather>
Would drinking melted ice water from Mars taste like sparkling water?
Muze
# Would drinking melted ice water from Mars taste like sparkling water?

(Asked by: username_0 on 2019-01-27)

Does water on Mars form from the atmosphere as ice free from salt?
Does water desalinize through the evaporation and transpiration?

When the fresh top ice is placed in a container then pressurized to melt, would the water be carbonated?

Particulates of salt and dust is less in the atmosphere during a Martian winter so would the ice that forms be also drinkably cleaner?

<https://space.stackexchange.com/questions/33884/how-to-drink-water-on-mars>
<https://earthscience.stackexchange.com/questions/16076/how-salty-can-ice-be>

[![enter image description here](https://i.sstatic.net/gwI9m.jpg)](https://i.sstatic.net/gwI9m.jpg)
<https://kottke.org/18/12/a-massive-ice-filled-crater-on-mars>

**Tags:** mars, water, weather


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## 1 answers

### Answer by username_1 on 2019-01-27. Score: 8 | Accepted answer

Any ice that forms from water will be free of salt -- the process of crystallization does an excellent job of removing impurities.

*But* that's only when freezing out of liquid water, which is not a process that happens today at the Martian surface. When ice forms out of the air, it forms as tiny crystals -- "hoar frost" we call it on Earth -- and forms *on* substrates, such as grains of sand. Since the soil of Mars is laden with salts of various sorts (including things a lot nastier than NaCl, such as perchlorate salts), it's hard to believe that the Martian hoar frost wouldn't be contaminated with salty sand and dust.

And, of course, the Martian atmosphere has dust suspended in it which is continually precipitating out and dust which is blown up by the not-infrequent dust storms and dust devils and all of this falls on any newly-formed frost.

It's very hard to see how there could be any macroscopic ice deposits on Mars that don't have dust and salt as impurities.

> **Comments:**
> **username_0**: https://en.wikipedia.org/wiki/Brine_rejection  

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