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Comment by basementcat | Hacker News Reader

One of the interesting consequences of water on Mars is the fact that it can be used to make methane and oxygen (used by both SpaceX's Raptor and Blue Origin's BE-4 engines). This potentially increases the amount of cargo one can carry from Earth to Mars as one no longer needs to bring hydrogen (for the Sabatier process for making methane) from Earth for the return trip back to Earth

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That sounds like a ridiculous waste of such a scarce resource.

>According to the researchers, 40 percent of the near-surface material of the 15,830 square mile (41,000 square kilometer) region could be water ice.

That’s potentially billions of tons of water ice.

Why? This is one of the only economic advantages for settling mars; serving as a lower-g refueling station.

Refueling for what? The realities of orbital dynamics mean that Mars isn’t a convenient stopping place on the way to say, the outer solar system. I don’t have the numbers in my head but the delta-v requirements to intercept, match velocity and land negate any potential refueling benefit in my understanding. (Not to mention the added complexity vs a straight shot, this is a lot to pull off even in a sim like KSP)

You might be able to make an argument for refueling bases on Mar’s tiny moons with their negligible gravity wells for Martian missions themselves but that’s about all I can see.

What am I missing?

But what if you built a base there that continuously flung refueling pods into orbit? Make these pods leave orbit to rendezvous with another craft somewhere else rather than the craft needing fuel to come to a stop on Mars.

You're not missing much, but orbital transfer hooks from Mar's moons work out.

Unless the water is replenished somehow, sending it all off-planet would mean no one could settle Mars.

How much water do you think is on Mars?

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