- it landed upright and tipped over
- transporting water to orbit, the moon, or beyond, is expensive. Mining it may be cheaper.
- not everything needs to be a critique of capitalism
this post was submitted on 30 Jan 2024
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It's not to bring back to earth, it's to use in space, water is heavy and it's crazy expensive to put water into space.
Water is:
- a source of oxygen for breathing
- a source of hydrogen for rocket fuel
- a source of hydrogen for fuel cells for power generation
- for drinking (obviously)
- for sanitation
- for growing food
- fantastic radiation shielding (important when you don't have an atmosphere to absorb solar radiation) - embed water tanks in your habitat walls or just mount them on the outside - nice layer of cancer prevention
So yeah, there's too many uses for water in space and it's really difficult to lift into orbit from Earth. Even if some future moon base starts producing an excess of water, it'll be used to resupply other space habitats or vehicles.
thanks for the clarification
More like, teaching moment. Keep on learning!
Is capitalism so prevalent, we're running out of ocean already?
I have to say, I expected smarter takes in a community about space
Certified Kerbal Space Program moment
What a bullshit title. We know exactly why it still works.
I rolled my Toyota. I just rolled it back over with some guys truck and drove it home. It spit all the oil out the intake. Filled it back up and drove it at least another 20k before I killed her. But even then I doubt it's actually dead.
~~Heroes~~ Toyotas never die
To further break down what others are saying about the cost to send water to space, it cost thousands of dollars per kilogram to put something into orbit. Every extra bit of mass you want to send up needs extra fuel. The numbers are a bit all over the place depending on which rocket you use and other factors, but as a rough rule of thumb after googling around a bit, you can kind of figure on it taking about 100kg of fuel to shoot 1kg of payload into space, which means at the low end that 1kg costs around $5,000 to launch. That's how much it costs to fight gravity and air resistance to get into space.
I'm gonna bounce around between units a bit because I'm American and I think in our crazy units by default. Generally speaking, an adult needs about a gallon of water a day. That's a bit less than 4 liters, a liter of water weighs about 1kg. So just to get 1 crew members water supply for one day, you're looking at about $20,000. Multiply that by however many crew members you have and how many days of water you need, and it adds up fast. And that's before you account for the water you may need for other uses, experiments, equipment, etc. Once it's up there, space vessels are mostly a closed system, you can recycle the water you have up there to some degree, but there will be some losses, it takes some time and energy to reclaim that water, and you don't want to be skating by with exactly as much water as you theoretically need, you want to have some in reserve in case it's needed.
The ISS has a crew of 7 people. Even if we assume our water recycling is efficient enough that the water you used yesterday can all be reprocessed today and be ready to be used again tomorrow without any loss (which I'm sure isn't the case) you'd still probably want at least 3 days of water per person, so you have at least 1 day of reserve water just in case it's needed (in reality I'm sure they probably need several days worth of water, if not a week or a month's worth) so 3 gallons x 7 crew members x $5000 = $105,000 at a theoretical minimum just to send up the ISS crew's water supply, and again the actual cost is probably several times that much.
And even if water magically had no weight, it still takes up space. For pretty much all practical purposes water is incompressible, you can't really make a kg of water take up any less space no matter what you do to it. That's space that could potentially be used to send something else up but can't because you need to send up the water.
The moon, however, has about 1/6 of the earth's gravity, and no real atmosphere worth mentioning so no air resistance to fight against, so you need a lot less fuel to get something into space from the moon. So if you have a moon base that's capable of extracting water on the moon, it could be a hell of a lot cheaper to send that water to wherever else you might need it in space than if you launched it from earth.
Not to mention any other resources we could potentially get on the moon, Mars, asteroids, etc.
And as others have mentioned, we could potentially split that water into hydrogen and oxygen to use as rocket fuel (and breathing oxygen.) Looking longer-term, if we manage to end up with a self-sustaining moon base that's able to grow their own food, and meet their other needs from the moon's resources with excess to spare, the moon could essentially become the first pitstop on the way to other planets. We send our astronauts up with just enough supplies to make it to the moon, then they load up with more fuel, oxygen, food, water, etc. and head off to their destination from there, saving us the cost of launching all of those supplies into space. Kind of like if you were to start off on a road trip with a quarter tank of gas because you know just across the state line the gas is a lot cheaper so you'll fill up there and save a few bucks. We're probably a long way off from that, but sometimes you have to plan well ahead.
There's a section of the book "A City on Mars" which covers the water we know about so far on the moon. In short, it's absolutely desirable, however there is not very much water in absolute terms, so we're looking at a gold rush type situation with the potential to exhaust what's there.
a gold rush type situation with the potential to exhaust whatβs there.
The older I get the more I think that this is humanity's (sole) core competency. sigh
Yeah, exhausting resources on the moon is a valid concern, it could be an invaluable, even necessarily asset to furth space exploration, but should probably be viewed as a stepping stone to something more sustainable, possibly asteroid mining, capturing comets etc.
I certainly glossed over that in my comment because it was already getting longer than I liked and I kind of wanted to focus on just the cost of getting things into space, but it is something that needs to be managed carefully or we lose an important foothold we might need to take the next steps.
I'm certainly no rocket scientist or astrophysicist so exact details are a bit over my head, and to be clear I'm talking about long term goals that are decades if not centuries out, but I'd kind of imagine that the ideal situation would be something like using the moon to get enough fuel to go mine a few comets and then use the ice from those comets to support future missions instead of getting it all from the moon.
That's what you get for inviting Australians to you team.
I love how everyone here is jumping on the comment about water in the ocean and writing essays about it. π€£
Obviously they are not after the water, the real reason is moon cheese as cow's are producing too much methane.
Wensleydale?
Don't follow much space news but guessing it's for colonization possibilities / setting up stations
I'm kind of excited about it honestly, especially with talks of setting up an orbital lunar station like the ISS. Maybe I've played too much KSP and Elite Dangerous, but I think the fact that they're starting to build truck stops in space is cool as fuck. It's going to open up a lot of new possibilities for space travel and infrastructure.
They aren't hoping to bring water back to earth. One of the biggest limiters to exploring other planets is getting the resources we need to travel and survive off of Earth. It's way easier to get off the moon, so moon bases mining water to drink, farm, and make fuel out of are a logical move.