
Water-Powered Spaceship Could Make Spaceflight Cheaper - gibsonf1
http://www.space.com/11230-water-powered-spaceship-mars-solar-system.html
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sorbus
Steam-propelled spacecraft. I fully approve.

However, this would likely not be especially cost-effective if we have to pull
all the water into orbit from earth; while the article mentions mining water
from asteroids or moons, it puts that in a hypothetical future, even more so
than using water as reaction mass, with refueling in low-Earth orbit proposed.

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cal5k
How does this compare in terms of thrust to, say, an ion engine?

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Symmetry
It all depends on how much they're able to heat up the water with their solar
panels, which is to say "who knows?"

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joeybaker
> "Water would be a big part of the space coach's body, too, according to the
> study. Packed along the habitat modules, it would provide good radiation
> shielding."

erm… doesn't that mean that once you use the fuel (water), your radiation
shielding is gone?

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redthrowaway
This is a minor and nitpicky point, but that's not what Phobos looks like.
It's oblong because its tidally locked, and it's long axis faces Mars, not the
direction of its orbit.

Also, that's a wee bit close. I demand accuracy in my sci fi watercolours.

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ComputerGuru
As soon as the next world war breaks out over water, I'm sure petroleum will
once more be the cheaper alternative :)

That, and no one will approve of shipping water (our _only_ renewable resource
FFS!!!) to outer space.

