Why not colonize Ceres?

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Why not colonize Ceres?

Postby pernero » Mon Oct 19, 2009 8:31 pm UTC

It has a giant ice-water layer, doesnt it?

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Re: Why not colonize Ceres?

Postby Vieto » Mon Oct 19, 2009 11:12 pm UTC

well, assuming we had sufficient shielding against a constant barrage of asteroids large enough to destroy Earth... yes, it would make a nice mining colony.

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Re: Why not colonize Ceres?

Postby poxic » Mon Oct 19, 2009 11:22 pm UTC

There's also the issue of shielding people from cosmic rays, which the Earth's radiation belt does quite nicely for us down here. It's a major problem around sending people to Mars. We haven't quite worked out a simple (cheap) way to do it.

Besides radiation, there are ordinary survival needs. Having lots of water on Ceres would be helpful, but we'd still have to ship everything else: air, food, shelter, toilet paper, broadband connections, that sort of thing. It would be like an outpost in Antarctica, but harder to get to and with fewer penguins to serve as emergency food supplies.
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Re: Why not colonize Ceres?

Postby Vieto » Mon Oct 19, 2009 11:41 pm UTC

poxic wrote:There's also the issue of shielding people from cosmic rays, which the Earth's radiation belt does quite nicely for us down here. It's a major problem around sending people to Mars. We haven't quite worked out a simple (cheap) way to do it.

Besides radiation, there are ordinary survival needs. Having lots of water on Ceres would be helpful, but we'd still have to ship everything else: air, food, shelter, toilet paper, broadband connections, that sort of thing. It would be like an outpost in Antarctica, but harder to get to and with fewer penguins to serve as emergency food supplies.


Although if we establish a sufficient moon base, it takes less energy to get from the Moon to Ceres, than from Earth to the Moon.

Also, your broadband connections might experience a few minutes lag...

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Re: Why not colonize Ceres?

Postby gmalivuk » Tue Oct 20, 2009 1:26 am UTC

Antarctica is infinitely more habitable than any other body in the solar system, and the Moon is about the only place after that where it makes any real sense to try and set up a colony at this point.
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Re: Why not colonize Ceres?

Postby oxy » Tue Oct 20, 2009 2:04 am UTC

What would be the point? I suppose as a forward base of operations for asteroid mining?

You really need to determine why you would do something that costs so damn much, rather than why not.

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Re: Why not colonize Ceres?

Postby poxic » Tue Oct 20, 2009 2:13 am UTC

Yeah, I kind of forgot that you don't need to import air into Antarctica. (For the purposes of discussion, not in general.) That alone is priceless, then we add in things like temperatures that are pretty damn cold but still MUCH warmer than the near-zeroK of space.

Or would a Sunward side of Ceres be roasting hot? I doubt it, since I haven't read of the Mars rovers being heat-proofed. (The heaters on the various joints and whatnot were a key part of their construction, iirc.)
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Re: Why not colonize Ceres?

Postby Carnildo » Tue Oct 20, 2009 3:13 am UTC

You hear about cold problems on the Mars rovers because it's harder for them to deal with. Heat is handled by simply making things somewhat reflective (ie. don't paint anything) so they don't absorb much during the 12-hour day. Cold is harder because the only way to counteract it is by expending energy, and the rovers don't have much to spare.

Wikipedia says Ceres has a daytime high surface temperature of 240K, which is a bit on the chilly side (winter in Minnesota), and an average temperature of 170K (makes Vostok Station look warm). Anyone who's worked in Antarctica can tell you that things get exciting when your equipment gets that cold.

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Re: Why not colonize Ceres?

Postby Cryopyre » Wed Oct 28, 2009 6:34 pm UTC

I think Ceres may be small enough that sufficient human habitation would heat it up, then it becomes a matter of losing heat rather than gaining it. Better situation though, in my honest opinion.

Still, Ceres is so damn far away, if we're going to start somewhere, I reccommend the moon. It's way closer and has plenty of materials to mine. (Not a lot of propellant unless we change the way our rockets function though).
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Re: Why not colonize Ceres?

Postby Random832 » Wed Oct 28, 2009 6:40 pm UTC

Holy...

I was looking up the Wikipedia article on "Colonization of the Moon" (to see what sort of exploitable mineral resources might exist on the moon, as you mentioned), and mentioned there really casually was "In September 2009 it was announced that NASA's Moon Mineralogy Mapper on India's Chandrayaan-1 had detected water on the moon."

http://www.hindu.com/2009/09/23/stories ... 770100.htm

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Re: Why not colonize Ceres?

Postby Cryopyre » Wed Oct 28, 2009 6:48 pm UTC

I like the idea of building an observatory on the moon, no atmosphere, readily available materials (metal, plenty of silicate). I think a moon base is feasible and a good place to start in future colonization efforts. Hell if it got off the ground, I'd go as a working hand (and there'd be plenty of need for people to shovel the gravel). I know everyone wants a Mars landing, but a base on the moon would be the true dawn of man's age in space.
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Re: Why not colonize Ceres?

Postby frezik » Wed Oct 28, 2009 11:40 pm UTC

gmalivuk wrote:Antarctica is infinitely more habitable than any other body in the solar system, and the Moon is about the only place after that where it makes any real sense to try and set up a colony at this point.


If you want to land a lot of stuff on the surface, it's cheaper to go to Mars than the Moon, because you can use aerobreaking.

The Moon makes more sense for industrial infrastructure, like making launches out further, putting up radio telescopes, asteroid mining, and building O'Neill cylinders. Mars makes more sense for colonization.
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Re: Why not colonize Ceres?

Postby Cryopyre » Thu Oct 29, 2009 12:33 am UTC

I'm gonna have to disagree with you. The moon is close, rife with materials and sunlight, and it's got less gravity. The less the better, because it will be the launchpad of space exploration.
Felstaff wrote:I actually see what religion is to social, economical and perhaps political progress in a similar way to what war is to technological progress.

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Re: Why not colonize Ceres?

Postby frezik » Thu Oct 29, 2009 3:56 am UTC

Cryopyre wrote:I'm gonna have to disagree with you. The moon is close, rife with materials and sunlight, and it's got less gravity. The less the better, because it will be the launchpad of space exploration.


I don't see what there is to disagree about. The delta-V required to land (not just orbit) on Mars is less than to land on the moon. That translates directly into less fuel. If you're bringing a lot of stuff with you, then Mars is cheaper. Mars can also probably be terraformed to the level of growing crops in the open within a relatively short amount of time (though not nearly enough for people to walk around without a breather). The atmosphere will also give at least some measure of protection against radiation. As a rock for people to live on, Mars is the better option.

OTOH, if you're bringing only the bare necessities to setup a mining operation for metals, fuel, and other materials, and then launching forward from there, then the Moon is the better place to go. Which one you pick will depend on your goals.
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Re: Why not colonize Ceres?

Postby Cryopyre » Thu Oct 29, 2009 4:36 am UTC

There are better materials on the moon than on Mars, and I'm not as concerned about landing, hopefully it will pay off as a launchpad for further colonization.

And it is worth remembering that distance is not a negligible factor. We can make the trip to the moon in under 3 days now, so the supplies brought with you can be lessened. This will automatically make a trip to the moon cheaper as you will accelerate less mass.

I'm not saying Mars should not be a future target, but I think space enthusiasts have become too hung up on that planet when the moon would be a far cheaper place, and therefore faster way, to begin space colonization. After a moon base is established need should propel plenty of advances in the technology involved to make Mars and Ceres and other targets feasible, but we must take the first step.
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Re: Why not colonize Ceres?

Postby Random832 » Thu Oct 29, 2009 5:09 am UTC

frezik wrote:
gmalivuk wrote:Antarctica is infinitely more habitable than any other body in the solar system, and the Moon is about the only place after that where it makes any real sense to try and set up a colony at this point.


If you want to land a lot of stuff on the surface, it's cheaper to go to Mars than the Moon, because you can use aerobreaking.


Yeah, but you can use lithobraking anywhere.

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Re: Why not colonize Ceres?

Postby Cryopyre » Thu Oct 29, 2009 5:42 am UTC

Random832 wrote:
frezik wrote:
gmalivuk wrote:Antarctica is infinitely more habitable than any other body in the solar system, and the Moon is about the only place after that where it makes any real sense to try and set up a colony at this point.


If you want to land a lot of stuff on the surface, it's cheaper to go to Mars than the Moon, because you can use aerobreaking.


Yeah, but you can use lithobraking anywhere.


Lithobraking :lol: , that's pure gold.
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Re: Why not colonize Ceres?

Postby Tass » Thu Oct 29, 2009 7:20 am UTC

I'd like to see you attempting lithobreaking on Jupiter :p

(Am I the only one who thinks that while the aero- part could have been spelled without the second 'e', the litho- one should definitely have had an 'e'?)

Yet another thought: They are actually planning on using some degree of lithobraking on the moon.

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Re: Why not colonize Ceres?

Postby SpazzyMcGee » Thu Oct 29, 2009 2:31 pm UTC

Vieto wrote:well, assuming we had sufficient shielding against a constant barrage of asteroids large enough to destroy Earth

The asteroid has few collisions. If it had "constant barrage of asteroids" it would have pulverized into dust or accreted into a full fledged planet long ago.

Cryopyre wrote:but a base on the moon would be the true dawn of man's age in space.

Until we ditch it. Sooner or later some politician will cut spending. Then again unlike the ISS which will sooner or later fall to the Earth the Moon base will always be there.

Meteorswarm wrote:The ISS is within the van Allen belts

No it isn't.

What is awesome about Ceres is that it is the closest source of large amounts of water. And all you people saying the Moon is better because of its minerals, it will be a long time before we have massive steel smelting plants lined across the lunar surface. Mining is hardly even considerable at this point in time.

However from what I understand about interplanetary travel Ceres is kinda useless for a refueling station. It would take months to reach Ceres moving at breakneck speed (which would require fuel) and it would take a lot of fuel to slow down to refuel there. It would be more fuel economical to just maintain your momentum and just keep on going to your outer planetary destination. Anything established on Ceres would have to be for pure research, which is a worthwhile goal seeing as it may harbor life.

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Re: Why not colonize Ceres?

Postby gmalivuk » Thu Oct 29, 2009 4:02 pm UTC

SpazzyMcGee wrote:
Meteorswarm wrote:The ISS is within the van Allen belts

No it isn't.

Not in the belts themselves. In the region enclosed by the belts, is what I believe Meteorswarm meant.
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Re: Why not colonize Ceres?

Postby Random832 » Thu Oct 29, 2009 4:57 pm UTC

Tass wrote:I'd like to see you attempting lithobreaking on Jupiter :p


I thought Jupiter was theorized to have a crunchy center underneath all that gas and liquid metal hydrogen

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Re: Why not colonize Ceres?

Postby Tass » Thu Oct 29, 2009 5:07 pm UTC

Random832 wrote:
Tass wrote:I'd like to see you attempting lithobreaking on Jupiter :p


I thought Jupiter was theorized to have a crunchy center underneath all that gas and liquid metal hydrogen


Yes, and I'd like to see you try to reach it.

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Re: Why not colonize Ceres?

Postby FrankManic » Fri Oct 30, 2009 2:58 pm UTC

So... what if we built a nice big... sensor... thingy somewhere in space near earth. Then we plot the path of some sizeable bodies that orbit reasonably close to earth. Then we send a rocket out to one, futz with it's trajectory a bit, dig a hole in it, and call it a reasonably radiation resistant space craft?

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Re: Why not colonize Ceres?

Postby FrankManic » Fri Oct 30, 2009 3:00 pm UTC

SpazzyMcGee wrote:
However from what I understand about interplanetary travel Ceres is kinda useless for a refueling station. It would take months to reach Ceres moving at breakneck speed (which would require fuel) and it would take a lot of fuel to slow down to refuel there. It would be more fuel economical to just maintain your momentum and just keep on going to your outer planetary destination. Anything established on Ceres would have to be for pure research, which is a worthwhile goal seeing as it may harbor life.


If you were feeling fancy you might be able to work out something where a craft passing Ceres rendezvous with a chunk of water ice or something heading in the same direction, then use that mass for reaction during braking. Be some pretty fancy flying, though.

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Re: Why not colonize Ceres?

Postby Random832 » Fri Oct 30, 2009 3:05 pm UTC

FrankManic wrote:If you were feeling fancy you might be able to work out something where a craft passing Ceres rendezvous with a chunk of water ice or something heading in the same direction, then use that mass for reaction during braking. Be some pretty fancy flying, though.


Reaction mass just provides (a way to get/lose) momentum; you still need energy. No such thing as a free lunch.

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Re: Why not colonize Ceres?

Postby Cryopyre » Fri Oct 30, 2009 4:27 pm UTC

Rod of Uranium? Atomic rocket style right?
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Re: Why not colonize Ceres?

Postby gmalivuk » Sat Oct 31, 2009 1:06 am UTC

Random832 wrote:
FrankManic wrote:If you were feeling fancy you might be able to work out something where a craft passing Ceres rendezvous with a chunk of water ice or something heading in the same direction, then use that mass for reaction during braking. Be some pretty fancy flying, though.

Reaction mass just provides (a way to get/lose) momentum; you still need energy.

Yeah, but with enough reaction mass to throw around, you don't need to use as much energy for a given delta-V.
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Re: Why not colonize Ceres?

Postby Ingolifs » Sat Oct 31, 2009 4:37 am UTC

I've been thinking about the possibility of solar panels on bases as far away as the asteroid belt. If the asteroids are to be mined for their minerals and rare metals, what is going to power the mining? I'd imagine the processes involved would be pretty energy intensive.

Ceres is roughly three times further away from the sun than Earth, so recieves 1/9 the energy from the sun per m2. The efficiency of solar panels decreases as the intensity of the light decreases, so a solar panel on Ceres will generate less than 1/9 the energy as one on earth would generate. Assuming these are pretty good solar panels (i.e. able to reach an efficiency of 30% or more on earth), how much solar-panel area would one need to fuel the mining operations?
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Re: Why not colonize Ceres?

Postby Josephine » Sat Oct 31, 2009 1:42 pm UTC

It would probably be more efficient (for large things, probes are an exception) to use nuclear power for Ceres, Europa, any outer bodies we would colonize. Solar is just too weak at that distance.
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Re: Why not colonize Ceres?

Postby PM 2Ring » Sat Oct 31, 2009 3:22 pm UTC

Solar is just too weak at that distance.

You can concentrate the sunlight using parabolic reflectors. Big Fresnel lenses may be useful as well, but they are a bit more vulnerable.

I much prefer the idea of colonies in orbital space habitats, rather than on various asteroids, moons & planets. Asteroids will be useful mining sites, but I don't know if people will want to live on/in them. But they're definitely better than moons & planets because it so expensive going up & down gravity wells, unless you have some form of space elevator technology.

Artificial habitats have an advantage in that you can build them where you want them, so they can have convenient orbits, unlike most of the natural bodies in the solar system which are not so nicely positioned from Earth's perspective (apart from the Moon).

OTOH, I think that modified asteroids do have potential as habitats. I like Larry Niven's idea of finding a metallic asteroid, drilling a tunnel into its centre, packing ice into the centre, sealing the tunnel back up again, and then heating the whole asteroid with huge parabolic reflectors. Eventually, the asteroid gets hot enough to melt & when the heat hits the centre, the ice explodes into water vapour, hopefully inflating the asteroid into a giant metallic bubble. Obviously, some research and practice will be required to perfect the technique. :)

A related idea is to drill one or more tunnels into an asteroid, pack the tunnels with ice & then heat the asteroid to create a steam powered rocket engine. This could be used to adjust an asteroid's orbit, or to move it into an orbit that's closer to the Sun.

There's plenty of room for orbital industry & habitats orbiting the Sun at roughly the same distance as the Earth (1 AU). And the light level & temperature is nice here in the "Goldilocks Zone". :) It makes sense to have the bulk of space industry concentrated here, with various minerals coming from the asteroids.

We know that there are all sorts of interesting metals in the asteroids, and their relative abundance is often different to what it is in the Earth's crust. For example, the very useful platinum group metals are probably easier to find in the asteroids than on earth. And even the rocky asteroids will be useful sources of building materials & ceramic components. But I suspect that the most important "mineral" will be water. Obviously it is vital to life in its liquid state, and it can be electrolyzed to make oxygen. But it is also an excellent radiation shield. And ice can be used as a construction material, ambient temperature & pressure permitting. :) Water is also convenient to use as reaction mass for propulsion of space suits and small vehicles, but I expect there are less wasteful techniques for puttering around the immediate vicinity of a habitat.

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Re: Why not colonize Ceres?

Postby Random832 » Sat Oct 31, 2009 5:27 pm UTC

gmalivuk wrote:
Random832 wrote:
FrankManic wrote:If you were feeling fancy you might be able to work out something where a craft passing Ceres rendezvous with a chunk of water ice or something heading in the same direction, then use that mass for reaction during braking. Be some pretty fancy flying, though.

Reaction mass just provides (a way to get/lose) momentum; you still need energy.

Yeah, but with enough reaction mass to throw around, you don't need to use as much energy for a given delta-V.

I think I'm going to need to see a diagram to 'get' this, because as far as my understanding of the proposed solution goes, my initial reaction is "physics does not work that way".

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Re: Why not colonize Ceres?

Postby Josephine » Sat Oct 31, 2009 7:51 pm UTC

PM 2Ring wrote:OTOH, I think that modified asteroids do have potential as habitats. I like Larry Niven's idea of finding a metallic asteroid, drilling a tunnel into its centre, packing ice into the centre, sealing the tunnel back up again, and then heating the whole asteroid with huge parabolic reflectors. Eventually, the asteroid gets hot enough to melt & when the heat hits the centre, the ice explodes into water vapour, hopefully inflating the asteroid into a giant metallic bubble. Obviously, some research and practice will be required to perfect the technique. :)


that sounds awesome.
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Re: Why not colonize Ceres?

Postby gmalivuk » Sun Nov 01, 2009 1:48 pm UTC

Random832 wrote:
gmalivuk wrote:Yeah, but with enough reaction mass to throw around, you don't need to use as much energy for a given delta-V.

I think I'm going to need to see a diagram to 'get' this, because as far as my understanding of the proposed solution goes, my initial reaction is "physics does not work that way".

I suspect I was actually thinking power rather than total energy, and that's proportional to exhaust velocity, which can be lower if you have more mass to throw around.

There's some derivation and other explanation on the wiki page for the rocket equation, but the conclusion is that the energy requirement for a given delta-V (with total final mass m1 and exhaust velocity ve) is
[; E = \frac{1}{2}m_1\left(e^{\Delta v\ / v_\mathrm{e}}-1\right)v_\mathrm{e}^2 ;]
Eventually this is also approximately proportional to ve (with a slope of [; \frac{1}{2}\Delta v m_1 ;]). Unfortunately, it's not like that for especially small ve like you'd get if you wanted to use a gratuitous amount of reaction mass for a given delta-V

What I missed, because I was thinking power rather than energy, was that for particularly low exhaust velocities, you have to expend that power for a longer time to change your velocity, and *also* you have to move quite a lot of extra mass at the early stages of your burn. So the energy requirement actually grows as ve decreases further, if it's much below the desired delta-V.

(For some reason, the image I get in my head, whenever I think of someone on a ship with really low exhaust velocity but plenty of mass to spare, is of an astronaut throwing old shoes out the back of the ship, one at a time...)

Edit: Incidentally, if energy is the limiting factor and you can adjust reaction mass and exhaust velocity more easily, the ideal exhaust velocity (i.e. the one that minimizes total energy) for a given delta-V is
[; v_\mathrm{e}=\frac{\Delta v}{2+W\left(\frac{-2}{e^2}\right)}\approx 0.6275\Delta v ;]
Where W is the Lambert W-Function. This means you want reaction mass to be a bit under 80% of the total initial mass of your rocket (a mass ratio of 4.92).
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Re: Why not colonize Ceres?

Postby Random832 » Sun Nov 01, 2009 8:20 pm UTC

I've considered this some more and realized that (in addition to what you said), accelerating a large reaction mass to a low velocity takes less energy than accelerating a small reaction mass to a large velocity for the same momentum.

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Re: Why not colonize Ceres?

Postby Wolfkeeper » Sun Mar 06, 2011 1:05 am UTC

That's not quite true, the hieroglyphics above says that if you throw the reaction mass too slowly, it takes *more* energy to build up the same speed, than if you thow it a bit faster. That's because the rocket ends up exponentially bigger if the exhaust speed is small compared to the speed you need to gain.

Or if you throw it too fast, then the exhaust loses energy because the exhaust ends up going too fast backwards; you need hardly any propellant, but the momentum is proportional to the speed, but the energy is proportional to the speed *squared*. So too fast is wrong too, you're just wasting energy.

In fact there's an optimum exhaust speed for minimum energy.

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Re: Why not colonize Ceres?

Postby Izawwlgood » Sun Mar 06, 2011 1:14 am UTC

The moon has way less utility than Mars. Materials too. Ceres would be great if you could get through the ice, which, in the scheme of things, is probably pretty doable.

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Re: Why not colonize Ceres?

Postby Wolfkeeper » Sun Mar 06, 2011 1:50 am UTC

Ice isn't a problem, you can melt it (nuclear power or a solar oven) or dig into it, and then it's a meteor and radiation shield.

The big problem with Ceres is that it's expensive to get there. The delta-v from LEO is about 10 km/s which is a lot.

Still, after you've got there once, you can fairly easily return a huge hunk of propellant to Earth that you can use to go there afterwards.

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Re: Why not colonize Ceres?

Postby Izawwlgood » Sun Mar 06, 2011 2:31 am UTC

Issue I see with Ceres is we don't know what's at the middle. If it's got a rocky core, it might be useful for manufacturing, if it's ocean through and through (weird... but possible?) then it's probably not terribly useful.
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Wolfkeeper
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Re: Why not colonize Ceres?

Postby Wolfkeeper » Sun Mar 06, 2011 4:25 am UTC

A huge lump of water/ice would be amazingly useful actually. Water is rocket fuel (steam rocket or LH2/LOX). If Ceres has any easily extracted water then it's well worth mining. You could sling the water back towards cis-lunar space and it could propel vehicles all over the solar system from there.

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Re: Why not colonize Ceres?

Postby Aelfyre » Sun Mar 06, 2011 4:38 am UTC

Cryopyre wrote:I think Ceres may be small enough that sufficient human habitation would heat it up, then it becomes a matter of losing heat rather than gaining it. Better situation though, in my honest opinion.

Still, Ceres is so damn far away, if we're going to start somewhere, I reccommend the moon. It's way closer and has plenty of materials to mine. (Not a lot of propellant unless we change the way our rockets function though).



I *SO* wish we would just colonize the moon already! I want to see a Lunar based version of the James Webb Telescope only 100 times bigger and decked out for full spectrum analysis.

I wanna see *WAY* out there :)
Xanthir wrote:To be fair, even perfectly friendly antimatter wildebeests are pretty deadly.


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