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[andrea]

Hint: A Lunar base could be built for a "mere" $35 billion; I calculated that, under ideal circumstances and assuming solar panels of merely 15% efficiency, and putting a $50-60 billion price tag on the whole thing, exporting solar power to Earth at well below market price repays that in weeks. Solar power alone.

a lunar colony large enough for 2000 people and with enough solar panels to repay itself in a week and costs merely 35 billion?
that is an hard claim to believe. could you post some more information about how you calculated those numbers?

[PanH]

There is some civilians [Fusion generator] prototypes running, and an important test plant should be finished in 2020 (including already 3 years late). Lots of prototypes are running since years, even though they're mainly about testing, potential uses, and not much about energy production.
And it's already used since decades in military devices.

Wut?  I've not heard a thing about fusion power, civilian or military, having been "in use" at all.  They've got various machines where, for a few milliseconds or so they can pump in a huge amount of power and momentarily get...  well, I'm not even sure if they've broken even, just yet, but a (not so?) huge amount back for just that moment, straight from the fusion (or from the heat generated, or something)...  But they're a long way from being self-sustaining.

Unless I've been asleep and missed something.

Hydrogen bomb.

For civilians project, there is some reactors, most of them being built in 80s, for testing and application purposes. The ITER, which would technically work the same as a plant (but for thermal tests, mostly) is being built.
For others military projects, there is some lasers that are being built to improve the atomic/nuclear bombs.

The + (for electricity plants) :
No radioactivity
3 to 4 times more energy than actual nuclear plant
Easy to find fuel (˛H)

The - :
Need a lot power to actually start the reaction (i.e. atomic bombs are detonator for hydrogen bombs)

There's probably some other things, but I'm not an expert (or maybe we didn't discovered them yet).

[GreatWyrmGold]

Hint: A Lunar base could be built for a "mere" $35 billion; I calculated that, under ideal circumstances and assuming solar panels of merely 15% efficiency, and putting a $50-60 billion price tag on the whole thing, exporting solar power to Earth at well below market price repays that in weeks. Solar power alone.

a lunar colony large enough for 2000 people and with enough solar panels to repay itself in a week and costs merely 35 billion?
that is an hard claim to believe. could you post some more information about how you calculated those numbers?

It wasn't for 2,000 people; it was more of a "minimal" space base. But, if a $60-70 billion space station can pay for itself within weeks or months, it can pay for $250 billion in extensions for a bunch more people in months or a year, and probably get up to the 2-3,000 people mark within a decade or two. Plus the time to get the basic colony up.


And, PanH, there's a big difference between a bomb and a reactor. If you can't tell which a design is going to be, it's wrong no matter what the intention is.

[PanH]

And, PanH, there's a big difference between a bomb and a reactor. If you can't tell which a design is going to be, it's wrong no matter what the intention is.

A bomb is a reactor (well, for atomic bombs at least).

For the bomb, you let the energy out of control, for maximum damage.
For the plant (or civilian use), you use it for different purposes (testing, producing electricity, etc), which is quite more complex, and not fully mastered yet. I don't see any "wrong" there.

Hydrogen bomb was an exemple "in use".

[Sheb]

Well, I'd still like to see your estimate. Given that a Moon base would have to be underground for radiation purpose, I don't see how it would be less expensive that a underground base on Earth. As for the "self-sustainable" thing, that's the beauty of the Earth option. You don't need to be self-sustainable until shit hit the fan. And once shit happen, well, you can wait a decade and then move back to the surface.

Now, let's go through your list of possible fan-dirtying stuff:

Ignoring environmental issues as good problems, too?

Find me an environmental issue that can strip Earth of all life and remove its athmosphere and magnetoshpere and I'll consider it. Otherwise, the Moon environment is still way worse than the Earth's.

How about political crap? That could be more devastating than a war. If, for example, you put this hypothetical, expensive, base in Alaska, and after a war Russia annexed Alaska, what happens to the base? Even if this is unlikely, consider the basic concept: As long as a base is on Earth, it is susceptible to Earth-based attacks.

Well, while it's true, I though the point was to keep technology and stuff alive to help people after a civilizational collapse. If the Russians can annex you, good for them.

Seismic events would ruin your base. They're not much of a problem for a Lunar base near the surface, but an underground base hit by an earthquake would probably risk caving in.

That's why you don't build your base in a seismic area.

Your seal on the door had better be pretty good, or your little base is going to get water trickling in from rain or melting snow, assuming that the aquifers in the area are nonexistent or properly sealed.

Oh my! I didn't see this coming. If only we had access to waterproof materials! (Frankly, it's easier to keep water out than to keep moon dust out.)

How about your settlement breaking down because you're always a mile or several underground, with no chance to have fresh air, see the stars, or even be in a relatively open area?

You ahd me laugh out loud here. Because the moon is well known for it's gorgeous landscape and fresh air. Again, here is the beauty of the Earth option, you don't have to stay inside the whole time, you can actually go outside and go fishing or something.

Now, looking at it, it seems your "giant library" argument were not what's really motivating you, and that what you want is really a resting home for misanthropic libertarians. Well, I wouldn't mind sending them on the Moon either, but I don't think policy-maker should take that kind of objectives in account when discussing our space program.

[10ebbor10]

2. The rovers have a max speed of 500 meters a day, run out of power frequently(I'll mis you, Spirit) and are screwed every time a dust storm happens. Also shading increases energy absorbtion, so it doesn't help. It just increases overheating.

This came up the other day.  Can't remember which rover it was (Sojourner, Spirit or Opportunity), but when one of them landed, the power it collected was (IIRC) 900Wh.  Then the dust started to build up, and it fell, fell, fell, down to 350Wh.  250Wh would have been "death", they think.  Then a wind came along and dusted the panels clean.  And because of a more favourable elevation of the sun, at that latitude in that particular season, the panels actually produced more power than they had upon landing.  They had to schedule an afternoon "siesta" for the robot to prevent the electronics from overheating, having now more than enough power to run the robot for far longer than they could actually make use of it for.

Anyway, this station has a guy with a brush stored in the airlock, if that's still a problem.  And spare bits and pieces ready to be fixed if something like Spirit's semi-broken wheel happened to a bit of base equipment.

Spirit. In the end they ended up using the robot for astronomical observations at night to burn power.

As for the brush thingy, how are you going to brush away the dust in the athmosphere. It's not dust accumulation on the pannels that is the main problem(Though that forms a rather large energy and maintenance problem, as the dust is magnetic and tends to stick) but the fact that the sun is occluded by "fairly" frequent dust storms, which can remain in the atmos for up to half a year.

       3. Orientation mechanics clash with the fact that the station has to rotate. This combined with a large size means that the pannels will suffer severly from centrifugal force. After all, in order to get decent efficiency you have to point your cilinder at the sun, and only use one layer of pannels (any next layer would just be shaded by the first) This means that they have to extend a long way from the station, hence enormous centrifugal force. They'll tear the station apart.

You're designing the station wrong.  Even if you had to set your panels further out from the station, plenty of Earth structures withstand 1G, and can handle more.  It's quite possible to ensure that you can make the station withstand the centrifugal or centripetal forces, as necessary, for quite a range beyond the 1g 'nominal'.

I'd set up a stationary solar array station in close proximity (to allow some form of Broadcast Power to be easily used and coordinated) and not bother spinning it, if it were actually troublesome (and I don't think it is) to attach most of the panels to the rotating wheel/cylinder/whatever...

The stronger you make the structure, the heavier it becomes. It's a sort of balancing act. And seperating the station from it's powersource will make manoevering quite problematic, though still possible.

The only thing angular momentum does is creating artificial gravity and allowing the spacecraft to maintain it's current heading. It doesn't supply any force to negate gravity. (If it did that, It would either need to slow down or be producing infinitive energy)

I sort of understood where you were at with your original response here.  I thought you'd probably misunderstood what was meant (i.e., you can move space-stations around, doesn't need to be stuck in LEO at all), but where you're going with what you just said, I don't really know.

Are you, perchance, conflating the angular momentum of the station's own frame of reference ('artificial gravity', by way of applying centripetal force to the soles of those standing inside the wheel) with the angular momentum of the station travelling in whatever orbit/freefall path it is currently instanciated in?

You don't get it -- a space station with angular momentum need not be in orbit around anything.  It can go anywhere and be anywhere

This quote, and previous conversation, led me to believe that he thought that angular momentum would just negate any other gravitational influence and allow the station to just fly wherever it wants without significant energy expenditure.

I get the idea you have no bloody idea what you're talking about.

I think, perhaps because you're misunderstanding things that I think I understand, but that you're seemingly interpreting quite differently, I'm perfectly entitled to fire that statement back at you.  However, I'm going to restrain from saying that you misunderstand your understanding, because there may still be more confusions at my end, regarding one or more bits of what I've snipped...

It wasn't directed at you.

There isn't any free oxygen on mars, so any combustion requires twice the fuel mass per watt-hour,

Erm....  Combustion would use the same fuel, but need to be supplied more oxygen.  There's 0.13% Oxygen on Mars, IIRC, compared to nearly 21% on Earth, so you'd need to concentrate that oxygen to anything up to 160 times what it normally is.  Or less, if you can feed it faster without removing the "heat" third of of the "fire triangle".

I think you forgot to account for the fact that Mars atmos is only 0.6% as dense as Earths.

Nuclar batteries would be a sensible option, and these have been proven as a reliable and safe option on many, many space missions. Make them on Earth, in orbit or the Moon, and send them to Mars. Or send them down our space elevator - more on that below.

By "Nuclear Batteries", you mean Radiothermal Generators, yes?  I'm not sure they're quite as good as straight fission (or possibly available fusion) power generation plants.

IIRC, the devices so far rarely reached more than a few tens of Watts each.  (There was one which was an actual reactor at the core of the thermoelectrical jacket, which was quite powerful, though.  A few kW.  But I'd consider a standard reactor/turbine concept a bit more efficient, with the inevitable maintenance problems surely improved by future developments.  There's probably an intermediate step that's better though.  What's that Thorium concept supposed to be again?)

The largest scale use of Radiothermal reactors that I know of are some lighthouses in the polar circle. Furthermore, a thorium reactor is identical to a conventional one, with the exemption that it runs on Thorium instead of uranium. This results in less nuclear waste and less meltdown risk(Thorium has a much lower metling point)

There is some civilians [Fusion generator] prototypes running, and an important test plant should be finished in 2020 (including already 3 years late). Lots of prototypes are running since years, even though they're mainly about testing, potential uses, and not much about energy production.
And it's already used since decades in military devices.

Wut?  I've not heard a thing about fusion power, civilian or military, having been "in use" at all.  They've got various machines where, for a few milliseconds or so they can pump in a huge amount of power and momentarily get...  well, I'm not even sure if they've broken even, just yet, but a (not so?) huge amount back for just that moment, straight from the fusion (or from the heat generated, or something)...  But they're a long way from being self-sustaining.

Unless I've been asleep and missed something.

Iter should have a break even, and I believe they reached one at the National Ignition facility last year. For now, all fusion energy reactors use more energy than can be recovered from the heat they produce.

Well, unless you give me an exemple of something that can threaten a Earth base, yes, I'll consider you as an uninformed pessimist who like space. And war ain't it. Just dig deep enough, keep the location more or less secret. If there is anything that can threaten you, humanity is advanced enough they don't need your help.

"Just dig deep enough." Yes, self-sustaining underground bases are so cheap and easy...especially housing 2-3,000 people. How deep is it before it starts costing as much or more than a Lunar base to build and keep alive? (Hint: A Lunar base could be built for a "mere" $35 billion; I calculated that, under ideal circumstances and assuming solar panels of merely 15% efficiency, and putting a $50-60 billion price tag on the whole thing, exporting solar power to Earth at well below market price repays that in weeks. Solar power alone.) That's not good for ya? Ignoring environmental issues as good problems, too? How about political crap? That could be more devastating than a war. If, for example, you put this hypothetical, expensive, base in Alaska, and after a war Russia annexed Alaska, what happens to the base? Even if this is unlikely, consider the basic concept: As long as a base is on Earth, it is susceptible to Earth-based attacks. Don't buy that, either? Somehow you've made it immune to every kind of attack known to man? Seismic events would ruin your base. They're not much of a problem for a Lunar base near the surface, but an underground base hit by an earthquake would probably risk caving in. Still not good enough? What did you use to get down there? Your seal on the door had better be pretty good, or your little base is going to get water trickling in from rain or melting snow, assuming that the aquifers in the area are nonexistent or properly sealed. Too improbable? How about your settlement breaking down because you're always a mile or several underground, with no chance to have fresh air, see the stars, or even be in a relatively open area? (A lit dome a couple hundred feet across might help, while rendering it more vulnerable to attack or earthquakes.)
Not good enough for you? Gimme a bit.

I'd really like to see to see those calculations. Did you account for occlusion by moon dust, maintenance cost, launch costs, development costs, transmission losses and costs(largest obstacle, for example microwave requires you to evacuate a large part of Earth's sattelite network). I posted some calculations earlier in this or on another thread about orbital solar power production, and even with high efficiency low weight pannels, constant exposure, no maintenance and optimistical transmission costs, it was unlikely they'd ever get out of the costs. Considering launch costs (majority of the problem) to the moon are several (10 times or more) higher than to LEO (which isn't even a good place to place solar power, but I was giving them the benefit of doubt) I doubt you'd make a profit that easily.

-Solar flare: Survivable, and a Martian colony will be hit much harder than Earth.

Isn't Mars farther away from the Sun? And wouldn't a Martian base presumably be built with a temporary radiation shelter for stuff like this?

I was talking about an semiapocalyptical flare. The oh god, everything electronic is death kind. Or more positively, the aurorae equatorialis kind. Mars has no magnetical field, and the mars colony will most likely have less reserve supplies to replace stuff.

-WWIII: You really think that an off planet colony will be able to maintain neutrality? After all, an offworld location is one of your best assets to break the MAD stalemate

I can't imagine an offworld base being worth the resources it takes to attack, let alone the time. Enemy missile stockpiles and such are much bigger threats, and don't require you to lift nukes into space to attack them. Also, you're assuming that the colony is built by a government. Why would Russia, the US, North Korea, or anyone waste resources on, say, an AT&T base on the Moon when they've probably got a dozen or more Terran threats to nuke?

Any governement is not going to let you build a colony without infiltrating it. Especially in a cold war type scenario. Sure, nobody is going to attack it during the war, but it will be forced to take on allegiance before. Especially if there's a chance of humanity nuking themselves into extinction.

And besides, the requirements for a fully, completely autonomous colony are enormous.

Define "fully, completely autonomous." Once you have food, water, oxygen, shelter, and power, it seems you're mostly set. The first three can be mostly or entirely solved by greenhouses; shelter and power should be obvious.

Complete, high tech industry capable of producing parts to replace anything that fails. Medical infrastructure capable of making new medicine. Political structure and police system capable of sustaining the society. Basically, everything on Earth, pocket edition. Some way to resolve the oh god we're alone in the universe feeling.

Solar and wind power aren't enough for humans needs, as for the low production, and for the variability (because, you don't use the same amount of energy sleeping, the morning, the evening, night, etc).

Nice thing about non-Earth areas, they have acres to burn. Dust and low atmospheric pressure are still issues, but a bit of labor (maybe brushing off the panels once a week?) and using lots of windmills as a backup only can help compensate.

You're pannels won't be so nice to get dusty in one before the other. What really happens is that first you get a dust storm, severly reducing power while you can't do anything (What'd you going to do, brush the atmosphere?) and then wind settles and dust starts to rain down on a large part of the pannels. Secondly, magnetic dust. It sticks to the pannels, meaning specialized brushing equiptment.
Thirdly, wind mills are absolutely useless. Even at best times the wind is the equivalent of a slight breeze, and the martian conditions are merciless for rotating parts. My guess is that you'll end up spending more power on keeping the windmills heated to prevent them from breaking due to the temperature shifts than you'd ever get from them.

Also, one strong flare and your entire energy netword is fried, as there are no protective magnetic fields on Earth. And reinforced circuits ain't going to help you. The cost would simply be to large to bear.

Don't bet on fusion. I'm reminded of a quote about stem cells: They're 20 years away and always will be.

The fusion constant is actually 40 years, not 20.

Hydrogen bomb.

For civilians project, there is some reactors, most of them being built in 80s, for testing and application purposes. The ITER, which would technically work the same as a plant (but for thermal tests, mostly) is being built.
For others military projects, there is some lasers that are being built to improve the atomic/nuclear bombs.

The + (for electricity plants) :
No radioactivity
3 to 4 times more energy than actual nuclear plant
Easy to find fuel (˛H)

The - :
Need a lot power to actually start the reaction (i.e. atomic bombs are detonator for hydrogen bombs)

There's probably some other things, but I'm not an expert (or maybe we didn't discovered them yet)

The only reason the hydrogen bomb comes out positive is because you want to produce heat (so a 100% recuperation efficiency), and because the fusion stage is actually used as a trigger for the ternary fission stage.

Secondly, fusion plants are still radioactive. They just don't produce radioactive waste. The reaction does produce errant particles, which have to be stopped. This also causes lot's of wear on the inner reactor plating. Second gen fusion would mostly solve this, as electricity is litteraly a product of the reaction.
While the primary fuel is easy to find, both tritium and He-3 are extremely hard to find. The first can be made in labratories and in the reactor itself, but it still increases costs.
Other problems with fusion is the fact that they have to be extremely large scale, operate a ludricous temperatures* and cost a lot.

*The main point of the Iter is to test if the design can actually resist the heat.

[PanH]

The only reason the hydrogen bomb comes out positive is because you want to produce heat (so a 100% recuperation efficiency), and because the fusion stage is actually used as a trigger for the ternary fission stage.

Secondly, fusion plants are still radioactive. They just don't produce radioactive waste. The reaction does produce errant particles, which have to be stopped. This also causes lot's of wear on the inner reactor plating. Second gen fusion would mostly solve this, as electricity is litteraly a product of the reaction.
While the primary fuel is easy to find, both tritium and He-3 are extremely hard to find. The first can be made in labratories and in the reactor itself, but it still increases costs.
Other problems with fusion is the fact that they have to be extremely large scale, operate a ludricous temperatures* and cost a lot.

*The main point of the Iter is to test if the design can actually resist the heat.

You're not talking about hydrogen bombs, but about improved atomic bombs that use fusion to accelerate the fission reaction. Hydrogen bombs are in 2 parts : an atomic bomb, and an hydrogen bomb. The atomic bomb will detonate, allowing the fusion reaction, which is the thermonuclear explosion.

Fusion does produce radioactive waste, with a shorter life than the fission waste (only a few decades), but does not produce radioactivity. The helium produced isn't dangerous. If you're afraid of radioactivity by fusion plant, you should be afraid of the air radioactivity (and of the errant particles in the air too).
Tritium is produced in large quantity by our current fission reactors, so there should be no issue. You can also make deuterium only fusion reactions, and they will even produce tritium. You could indeed use Helium3 for the reaction, but there is no real point in it when a H˛ H^3 reaction produce the same quantity of energy (in fact, I've never heard of a prototype using He3).

There is different designs that are planned. The ITER will indeed need to be light up at a very high temperature. The point is to produce at least 10 times the energy received to heat it (50MW to 500MW for the ITER).
A nuclear plant of 1GW costs 1.1$ billion, the ITER cost currently 16€ billion (probably more till it's finished).

I also found some neat things. It appears USSR has sent about 40 nuclear reactors in space, for various experiments. US sent one, in 1965.

[PTTG??]

ITER is probably not going to be net power. Polywells, now, they are actually a potential. They're far simpler and cheaper than toruses, and something like a ten-meter sphere with our current technology would produce net energy. Unfortunately, the research is locked up in the Navy... for some reason they want a way to turn seawater into energy.

Then there's a couple other groups who say they're close, and they're reasonable as well. The only people I really, really don't think are going to work out are the LENR people with their magical damp bricks.

No matter what the ultimate system is, I think we'll see breakeven before the end of the decade, and commercial power production perhaps ten years after that point.

If we're really lucky, we'll get proton-boron polywell fusion, which means you could fit a fusion reactor, shielding, generator and all, in something like one or two shipping containers. Large boats and small buildings could be entirely fusion-powered; Everything from coal to solar, fission to biogas, would be obsolete. (Not hydro, though, that's easily the cheapest power supply, just hard to find.)

Even if that isn't possible, the simpler, lower-power H-H fusion would still replace all utility- and industrial- scale power plants.

[PanH]

No matter what the ultimate system is, I think we'll see breakeven before the end of the decade, and commercial power production perhaps ten years after that point.

I think that's a bit optimistic. I'd say at least 30 years.

ITER is about feasibility, so won't produce anything.

[10ebbor10]

The other basic type of nuclear weapon produces a large proportion of its energy in nuclear fusion reactions. Such fusion weapons are generally referred to as thermonuclear weapons or more colloquially as hydrogen bombs (abbreviated as H-bombs), as they rely on fusion reactions between isotopes of hydrogen (deuterium and tritium). All such weapons derive a significant portion, and sometimes a majority, of their energy from fission. This is because a fission weapon is required as a "trigger" for the fusion reactions, and the fusion reactions can themselves trigger additional fission reactions.[10]

Only six countries—United States, Russia, United Kingdom, People's Republic of China, France and India—have conducted thermonuclear weapon tests. (Whether India has detonated a "true", multi-staged thermonuclear weapon is controversial.)[11] All thermonuclear weapons are considered much more difficult to successfully design and execute than primitive fission weapons. Almost all of the nuclear weapons deployed today use the thermonuclear design because it is more efficient.

Thermonuclear bombs work by using the energy of a fission bomb to compress and heat fusion fuel. In the Teller-Ulam design, which accounts for all multi-megaton yield hydrogen bombs, this is accomplished by placing a fission bomb and fusion fuel (tritium, deuterium, or lithium deuteride) in proximity within a special, radiation-reflecting container. When the fission bomb is detonated, gamma rays and X-rays emitted first compress the fusion fuel, then heat it to thermonuclear temperatures. The ensuing fusion reaction creates enormous numbers of high-speed neutrons, which can then induce fission in materials not normally prone to it, such as depleted uranium. Each of these components is known as a "stage", with the fission bomb as the "primary" and the fusion capsule as the "secondary". In large, megaton-range hydrogen bombs, about half of the yield comes from the final fissioning of depleted uranium

There are no fusion only bombs. (To be fair, there are a few designs for them, but those are theoretical. The so called neutron bombs).

Fusion does produce radioactive waste, with a shorter life than the fission waste (only a few decades), but does not produce radioactivity. The helium produced isn't dangerous. If you're afraid of radioactivity by fusion plant, you should be afraid of the air radioactivity (and of the errant particles in the air too).
Tritium is produced in large quantity by our current fission reactors, so there should be no issue. You can also make deuterium only fusion reactions, and they will even produce tritium. You could indeed use Helium3 for the reaction, but there is no real point in it when a H˛ H^3 reaction produce the same quantity of energy (in fact, I've never heard of a prototype using He3).

I colored the contradicting parts. Let me correct you on them. Fusion produces no radioactive waste. . After all, the only product is nonradioactive helium.You seem to be confusing fusion with thorium fission (which is the new technology that only has several decennia of radioactive waste). However, it does actively produce radioactivity, in the form of the very rapid neutrons expelled as a byproduct. These are very dangerous, (Look up the neutron bomb for more information) but should be contained within the reactor itself.

Secondly, tritium production in current day fision plants actually quite rare. Enough to be a danger to the reaction, but maybe not enough to be economical.

Thirdly, the reason why He-3 fusion is considered is because, as I said before, it doesn't produce any radiation (or not as much anyway) but rather directly expels electrons, which can be captured to form electricity directly as a reactor product, without needing an intermediate stage. This means that it can achieve efficiency rates of up to 70%, and maybe more, as opposed to the 33%-40% that's normal for heat to turbine reactors.

The Iter power plant doesn't include a generator, but should technically be capable of producing power.

[PTTG??]

No matter what the ultimate system is, I think we'll see breakeven before the end of the decade, and commercial power production perhaps ten years after that point.

I think that's a bit optimistic. I'd say at least 30 years.

ITER is about feasibility, so won't produce anything.

I've seen people- serious people- talking about reaching breakeven in the next five years, or four or two or "we've tested the laser with empty pellets and it works, and we test it with full fuel pellets in 2013". The fact of the matter is, 50 years ago, they said fusion was 60 years away. 20 years ago, they said it was 30 years away. 10 years ago, they said it was 20 years away. And every time, the naysayers said "You always say it is X years away".

WELL GUESS WHAT, WHILE X > 0; X--;, BRO!

[PanH]

There are no fusion only bombs. (To be fair, there are a few designs for them, but those are theoretical. The so called neutron bombs).

This is what I said. Hydrogen bombs use the energy from the atomic bomb for a fusion reaction, which produce the thermonuclear explosion. I have a bit of doubt about from what reaction comes the most power, because that's not exactly what tells me other sources, nor correspond with the development "booster" and "super" design. But there's no really public studies about it.
Actually, I've been surprised to find out that neutrons bombs exists, but are not as inefficient. They use the same design as hydrogen bombs (so, with an atomic bomb too), but release the neutrons which makes it more aggressive towards organic and electronic, but with smaller explosion.


Now, deuterium-tritium reaction, which is the considered reaction (I've seen nowhere talking about H˛ He-3 reaction, nor about "catching electron from reaction").
Deuterium : 1 proton, 1 neutron
Tritium : 2 neutron, 1 proton
When combined, they'll form a 2 neutrons, 2 protons (Helium), and a free neutron. The helium is not radioactive. But the neutron (not radioactive in itself), if absorbed by other particles, can often make the said particles radioactive, like the inner plating (which will then be radioactive waste).
Neutrons in itself are not radioactive. Of course, it's dangerous for (as said), organics, as if you become radioactive yourself (do not try this at home), but on other materials, it change them into radioactive waste (most are not very dangerous, but some can be nasty). For more things about radioactive effects of neutrons.

From what I saw about tritium, there is currently an unused stock from current nuclear (fission) plants which will not be enough for future or electricity use. That's why they are trying with ITER, to produce tritium, within the reactor, with lithium and the help of said neutrons.

Fakedit : I'd rather be pessimist and surprised, than be optimistic and dissapointed.

[GreatWyrmGold]

Well, I'd still like to see your estimate.

I will if I can find it.

Given that a Moon base would have to be underground for radiation purpose, I don't see how it would be less expensive that a underground base on Earth.

The biggest difference is the depth. On Luna, you probably don't have to bury the main living quarters more than a dozen meters, if that, and some things can be closer to the surface. If you're protecting your base from every kind of attack, that's probably miles you need to haul the rock up.

As for the "self-sustainable" thing, that's the beauty of the Earth option. You don't need to be self-sustainable until shit hit the fan. And once shit happen, well, you can wait a decade and then move back to the surface.

Well, I can't agree with this philosophy, but it's a matter of opinion so I won't argue.

Now, let's go through your list of possible fan-dirtying stuff:

Ignoring environmental issues as good problems, too?

Find me an environmental issue that can strip Earth of all life and remove its athmosphere and magnetoshpere and I'll consider it. Otherwise, the Moon environment is still way worse than the Earth's.

I can't, but it doesn't take nearly that much to wipe out all civilization on Earth or even all humans on Earth.

How about political crap? That could be more devastating than a war. If, for example, you put this hypothetical, expensive, base in Alaska, and after a war Russia annexed Alaska, what happens to the base? Even if this is unlikely, consider the basic concept: As long as a base is on Earth, it is susceptible to Earth-based attacks.

Well, while it's true, I though the point was to keep technology and stuff alive to help people after a civilizational collapse. If the Russians can annex you, good for them.

You're assuming the Russians want to keep the base...and that their annexing of the base didn't destroy it...and that the Russians want to send food to the base like you suggest...

Seismic events would ruin your base. They're not much of a problem for a Lunar base near the surface, but an underground base hit by an earthquake would probably risk caving in.

That's why you don't build your base in a seismic area.

So earthquakes NEVER happen in non-seismic areas?

Your seal on the door had better be pretty good, or your little base is going to get water trickling in from rain or melting snow, assuming that the aquifers in the area are nonexistent or properly sealed.

Oh my! I didn't see this coming. If only we had access to waterproof materials! (Frankly, it's easier to keep water out than to keep moon dust out.)

Nothing lasts forever. Are you going to send someone up to the surface every so often to examine the waterproof coating and replace it somehow?

How about your settlement breaking down because you're always a mile or several underground, with no chance to have fresh air, see the stars, or even be in a relatively open area?

You ahd me laugh out loud here. Because the moon is well known for it's gorgeous landscape and fresh air. Again, here is the beauty of the Earth option, you don't have to stay inside the whole time, you can actually go outside and go fishing or something.

1. You're assuming that the catastrophe in question is one where that would be wise...
2. Luna does at least have wide-open spaces.

Now, looking at it, it seems your "giant library" argument were not what's really motivating you, and that what you want is really a resting home for misanthropic libertarians. Well, I wouldn't mind sending them on the Moon either, but I don't think policy-maker should take that kind of objectives in account when discussing our space program.

If you can't even read my explanations for why right, and keep changing your interpretations, why do I bother arguing?

Not dealing with ebbor's huge megapost.

Any governement is not going to let you build a colony without infiltrating it. Especially in a cold war type scenario. Sure, nobody is going to attack it during the war, but it will be forced to take on allegiance before. Especially if there's a chance of humanity nuking themselves into extinction.

Wait, why are you assuming I'm having the base built during the war, or that such people wouldn't be allowed in the colony if there was room and they didn't try to sabotage the base?

You're pannels won't be so nice to get dusty in one before the other. What really happens is that first you get a dust storm, severly reducing power while you can't do anything (What'd you going to do, brush the atmosphere?) and then wind settles and dust starts to rain down on a large part of the pannels. Secondly, magnetic dust. It sticks to the pannels, meaning specialized brushing equiptment.

Good thing my main plans are for Luna, then.

The fusion constant is actually 40 years, not 20.

Whatever, the idea's the same.

Oh, and by the way: Since this is a thread which the title and OP pretty clearly indicate is to be talking about a future Martian colony and I have to convince other people that we will and have reasons to colonize other worlds--when there's already attempts to do so underway--I see no point in continuing following this thread. If it was a thread titled something like "Should we colonize space?" or with a similar OP, this would be fine, but as it is...nope. Good day. Have fun discussing fusion in a thread about space colonization.

[andrea]

well, discussion about what could make colonies feasible, including power sources , isn't much off topic.

[Sheb]

Actually, my point is that we'll go to Mars for pretty much the same reason we went on the Moon. Because we can.

Actually, can you state your reasons for a Moon colony once and for all? It seems to be changing to me. I think we got a misunderstanding there.

Oh, and humans are like friggin' cockroach. We survive on the ice shelf of the arctic and in the desert of gobi, in the jungles of the Amazons and the plains of Africa. And that was before we had all that fancy tech.