Thinking about all this space exploration stuff that’s been going around lately, I started wondering: for long-term space missions – whether a colony on the moon [theramin ON] or travel to distant planets, how are the astronauts going to get the water they need?
Now, I have read on NASA’s website about the recycling systems used on the ISS, but I wonder if moon colony [theramin ON] or a mission to Mars would present a more difficult problem, given that the ISS appears to be resupplied on a fairly regular basis. It seems like it’d be harder to send necessities to the moon or to a spaceship hurtling towards Mars, making me wonder if we would have to send a rather large stockpile of water up to the heavens to keep the astronauts clean and hydrated.
On the moon, there may be hydrogen and oxygen locked up in various minerals - if you have abundant power (i.e. a nuclear reactor), separating it should be relatively simple.
Oh, and on the way to mars, yes, they’d have to lug a good deal of water with them, recycling intensively - there’s talk of using the water as shielding from solar radiation.
Best current information suggests that there’s plenty of water on Mars, so a colony there wouldn’t have this problem. There’s also good evidence for frozen ice hidden from sunlight in craters at the poles of the Moon, so that resource could last for a while.
Water is actually fairly abundant in the solar system (and, hypothetically, the rest of the universe). It’s a major ingredient in comets, on Jupiter’s moon Europa, in NEOs (near earth objects like loose-gravel asteroids), in the Kuiper Belt, and so on. All those sci-fi stories, like the V miniseries, about aliens coming to Earth to steal our water are basically hogwash.
As far as putting this to practical use: John S. Lewis’s book Mining the Sky describes how a craft could dock with an asteroid and plunder it for water and related volatiles, for human consumption and/or fuel. If you’re looking for more information, start there.
I’ve also read some far-out SF speculation that a clever way to transport water with a deep space mission and at the same time protect the passengers from cosmic rays would be to freeze the water on the outside of the craft, and then seal it against sublimation. Since you’d have the same amount of mass to accelerate whether the water is outside or inside, and since you don’t have to worry about aerodynamic properties in space, it seems like a clever notion to me: Just encase the vessel in ice, more than you need, and use it as necessary from the inside. Sort of a James and the Giant Peach approach.
My initial googling suggests that whereas there’s good evidence of water in Mars’ past, where it’s now to be found is rather a mystery. Where would you have your colony go to find it?
The polar caps on Mars are suspected to be a mix of frozen carbon dioxide (dry ice) and water ice. This from spectrographic data.
Also, all the water that resulted in the changed landforms had to go somewhere. Most planetary scientists would agree that it’s reasonable to presume that permafrost can be found by digging deep enough.