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Comment by vectorjohn | Hacker News Reader

I'm not sure if you were suggesting Ceres as an alternative to Mars, but there's plenty of water on Mars.

I guess the nice part about Ceres is the low gravity. A settlement there would be able to easily use its resources for further space exploration or whatever. And people could get home more easily.

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One local gravity advantage is its obviously easier to structure and pile 3 meters of soil for micrometeor protection and thermal stability or whatever the standard is. If you're going to dig and pile up dirt as part of building your settlement, may as well do it low gravity.

Other than the distance thing, it would be a pretty awesome settlement location.

If you want a microgravity settlement a near-Earth asteroid would be more convenient - or just a space station. But microgravity is not good for the health of people living there.

Those may be a little too micro. Maybe an artificial gravity space station that slowly orbits Ceres :) Now we're getting crazy. But really, that may be an optimal setup.

That's a pretty big jump between Ceres' small but still significant gravity and being in total freefall. Granted, Ceres is pretty tiny compared to Mars or even the Moon, but we don't know at what point on the spectrum between "microgravity" and "Earth" do we see noticeable health risks. Maybe we're finely tuned for Earth gravity, and we'll suffer even on Mars. Maybe it's just the freefall that's the most harmful, and that any gravitational sense of "down" will be healthy enough for a settlement to actually be viable. Some long-term lunar habitability experiments would be a good first step to finding that point.

If asteroid mining starts to catch on, Ceres would be a really nice spot for staging mining expeditions, materials processing, etc. Combined with the abundance of water ice, it could be even more ideal of a colonization target than even Mars, especially if the effects of longterm exposure to its lower gravity can be identified.

>noticeable health risks

There might also be a continuum and people living in freefall need to exercise 9 hours a day to live long term, but on Ceres its only 3 hours a day, so there's an interesting economic labor argument WRT 6 saved labor hours per day, or whatever the numbers work out to.

I imagine it be easier to fake earth-like gravity on a station above a planet (say a rotating wheel space station) than on the planet. Would a space elevator be possible somewhere like Ceres with lower gravity / atmosphere? If so, it would be much easier to resupply water and materials.

I'm sure a space elevator would be easy on Ceres, but with gravity like that, why bother? An electromagnetic launcher could be pretty small there, maybe even small enough to launch people without too much effort. Or regular rockets, since something very small would be able to escape.

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