Water on the moon

Point out news stories, on the net or in mainstream media, related to polywell fusion.

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rj40
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Post by rj40 »

There are places (the poles) on the moon where there is water. And in addition to drinking water that means - fuel, air, food, and radiation shielding concentrated in two relatively small regions. Add to that the idea that it ought to be possible to pick a high latitude and string up a set of pole girdling power lines, power stations and solar panels where some of the constituents would always be in direct sunlight. So now we have a constant power source to make water, rocket fuel, and whatever else. When one thinks how difficult it is to get substantial amounts of water into space, it seems like the lunar poles could open up the solar system.

This is sort of like one country or region on Earth having all the fossil fuels, radioactive elements, steady winds, ocean waves, abundant rivers, fertile soil, and potable water. Oh yeah, and clean air.

I wonder if anyone would start a war over such a region? Nah.

Do you think the major space faring nations aren’t thinking about this? OK, perhaps not very seriously yet. But what about 50 years from now? You know, when we finally get nuclear fusion. I smell a blockbuster Tom Ligon novel in this. See you at the Hugo’s Tom.

:-)

Of course a working BFR would offer an alternative to some or all of this, but until then…

MirariNefas
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Post by MirariNefas »

The poles aren't as good for titanium. You find more of that on the near side of the moon (for some reason I don't understand). Not sure if the poles will be good for He-3. I guess the water migration model would work as well for helium. Otherwise, you'd expect all that to be around the titanium deposits or around the far side of the moon.

There's also other bits of real estate up there you know. There's plenty of water on asteroids, among other valuable elements. So, no, it's not really like one region on Earth having everything valuable.

rj40
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Post by rj40 »

You gotta wait for an asteroid to come around. Get what you want and then leave. There is time to build a base on the moon, and the orbit will allow more frequent visit to the same place. After a time, infrastructure could be built up on asteroids too. But why not start from a place you could get to on a routine basis and then follow on to asteroid. Once enough asteroids are setup, routine visits could be made as orbits setup.

Not sure, but I am reading the He-3 may not be as useful for fusion as advertised. Titanium is good stuff. So base at a pole where most of the easy (we hope) water and sunlight is (and thus rocket fuel and drinking water, and water for food) and then move out to the rest of the moon. I think water and constant sunlight would be more useful than titanium. UNLESS you are going to the moon for just the titanium. But maybe even then...

MirariNefas
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Post by MirariNefas »

Oh, I didn't mean to say that the poles aren't hot shite. They are. But there's credible second bests out there. So when you consider things like international competition, you have to ask, what's more profitable - going for broke to get a pole, or just selling titanium to buy pole-ish water? For some players, it will make sense to hold back, let the tech mature, enter the game late, and do something like claim an asteroid. Maybe they'll bring along fusion engines and capture the thing into a closer orbit.

My understanding of He-3 is that it's easier to fuse than p-b11, and still produces negligible radiation and direct energy conversion options. The only problem is that it's on the moon, and people here feel that polywell or similar could manage the p-b11 option well enough anyway. I'm under the impression that you could manage higher power densities with He-3 than you could with p-b11, so it makes sense for high performance space operations.

taniwha
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Post by taniwha »

Capturing an asteroid of worthwhile size will take decidedly non-trivial power-plant and drives. However, as a very large number of asteroids are available within Jupiter's orbit (and don't forget the Trojans), they're close enough that fusion powered ships might be able to do the trip without worrying about orbits except for when their path gets too close to the sun.

However, I think asteroids might not be all that useful, when the moons around Jupiter and Saturn should be much more interesting resource-wise.

Outbound comets might be interesting. Hitch a ride out of the solar system on a "free" colony ship.

MSimon
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Post by MSimon »

MirariNefas wrote:My understanding of He-3 is that it's easier to fuse than p-b11, and still produces negligible radiation and direct energy conversion options. The only problem is that it's on the moon, and people here feel that polywell or similar could manage the p-b11 option well enough anyway. I'm under the impression that you could manage higher power densities with He-3 than you could with p-b11, so it makes sense for high performance space operations.
Not true in a real reactor i.e. where the reactants are all mixed up. It reduces the radiation some. But there are the side D-D reactions to worry about.

The neutonicity of D-D is about 1/4 that of a fission reactor on a per reaction basis. That reduces to about 1/2 because in a fission job about 1/2 the neutrons are absorbed in the reaction.

But - here is the kicker: A D-D reaction produces 1/10th (BOE number) the energy a n-U235 reaction produces. So you get 5X as many neutrons per unit energy with D-D fusion (roughly).

Now if you get the side reactions down due to low thermal energy used to excite the reaction you gain a factor of 10 or 100. Nice - but not as exciting as an optimized pBj. Where the reduction (claims Nebel) is on the order of 1e6.
Engineering is the art of making what you want from what you can get at a profit.

MSimon
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Post by MSimon »

taniwha wrote:Capturing an asteroid of worthwhile size will take decidedly non-trivial power-plant and drives. However, as a very large number of asteroids are available within Jupiter's orbit (and don't forget the Trojans), they're close enough that fusion powered ships might be able to do the trip without worrying about orbits except for when their path gets too close to the sun.

However, I think asteroids might not be all that useful, when the moons around Jupiter and Saturn should be much more interesting resource-wise.

Outbound comets might be interesting. Hitch a ride out of the solar system on a "free" colony ship.
The nice thing about asteroids and comets is that they are already packaged for delivery.
Engineering is the art of making what you want from what you can get at a profit.

taniwha
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Post by taniwha »

If they're small enough.

If they're big enough, they might make reasonable "private islands".

It's the ones in the middle that might be too much of a PITA to do anything with.

Hmm, Goldilocks and the Three Asteroids?

MirariNefas
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Joined: Thu Oct 09, 2008 3:57 am

Post by MirariNefas »

Now if you get the side reactions down due to low thermal energy used to excite the reaction you gain a factor of 10 or 100. Nice - but not as exciting as an optimized pBj.
Not as exciting for ground based powerplants, anyway.

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