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[mainiac]

The other topic got sufficiently derailed that I thought I'd start another.  Here goes.

Suppose you were to speak to someone living in the pre-industrial world about the way people live today by jumping right into it by talking about hairdressers and computer programmers and delivery truck drivers.  They would be confused by how all this works.  How can the world feed itself without everyone farming?  Well there's tractors and fertilizers and irrigation and such.  But where do all those things come from?  Well there are factories and supply lines and retail stores and agricultural colleges.  But how is all of this afforded?  Just three centuries ago, nearly everyone was dependant on farming to make ends meet and couldn't dream of affording these things that are such a minor expense to us.  How could the world make something as complicated as a laptop?  It's all very confusing and everything is co-dependant, making a complicated story because you are approaching it backwards, starting at the end.

The way to approach things is to start your story by going back to the early 19th century and start discussing textiles.  Textiles of course are the first thing that were profitably industrialized.  Some people figured out how to use machines to make cloth much more easily, getting them a lot of money and freeing up a lot of labor.  That money and labor was used to do other things efficiently like steel and concrete and fertilizer.  And very quickly the process snowballed until everything is being done with machines and you have the industrial revolution.  Then things that used to be very expensive, like food and clothing, are now much much cheaper then they used to be.

When thinking about space colonization, we need to approach things the same way.  It wouldn't make sense to make a bunch of colonies on mars if everyone of them is going to have a huge price on earth.  It needs to be a sustaining cycle.  And that cycle needs to start somewhere.  That place is solar power.

Space has a lot of solar power.  Well, duh, you might think, the sun is everywhere.  But it really does.  There is no day or night in space, so a solar panel in space is already twice as efficient as on earth.  There is no atmosphere, increasing efficiency again.  There are no fluctuations due to clouds.  There isn't a need to kept it pointed at the sun.  No seasonal fluctuations.  All in all, space based solar panels should be about 4 times as efficient as earth based ones.

Now, you might be thinking that we'd need a long extension cord to get that electricity back to earth.  But there's an easier way, microwave power transmission.  It's safe, reliable and the loss in transmission would be fairly small.  Plus that power could be beamed anywhere on half the earth.  That means all the redundancy that we have on earth to deal with peak demands in different places and all the electricity lost in transmision would be reduced enormously.

So why don't we do this?  Because launching satellites from earth is really, really expensive, $3000 a pound or more.  But there is another way.  What if we made those satellites in space?  The moon has all the raw materials we need, silicon, iron, carbon.  And launching something from the moon is easy, even a catepault could do it.  The only problem is that there aren't any people living on the moon.  But what if there were?  This moon colony would be very, very profitable as it would have an export that the earth has a nearly limitless appetite for: electricity.  This would fuel further colonization.  And as the colony got bigger, manufacturing would get more efficient.  Eventually you reach a snowball effect and you start having a self sustaining move to the moon.

And once you have really colonized the moon, not just dusted your feet and placed a flag, the universe is your oyster.  Because we don't need to stay on the moon.  It's easy to leave the moon, remember?  We can make entirely artificial habitats in space with materials from the moon and the asteroids.  It sounds crazy but it's quite simple, just make a two mile across steel ring, spin it for artificial gravity and fill it with air.  Then all you need are a few mirrors and solar panels and you've created yourself a giant greenhouse to live in.  But this greenhouse would be far better then any greenhouse on earth.  No polution, a zero environment environment to do you manufacturing and construction in and a frictionless environment to handle all your transportation needs.  Plus expanding this environment would be easy.  You will never run out of space and there are enough materials in the moon and asteroids alone to sustain trillions and trillions of people.

It's difficult to take that first step.  The people who started the industrial revolution, by first tinkering around with textile machines like the spinning jenny, had no clue what they were starting.  But we can start the space revolution, the move into a low gravity environment.  And once we do, the process will eventually become self sustaining.  But the challenge is, can we take that first step?

[Nadaka]

Solar power in space may be 4 times more efficient for a given surface area when compared to earth, but it also costs a thousand times more for the same amount of power due to launch costs alone. Plus we have huge amounts of relatively unusable desert that can be filled with solar thermal power plants that don't require the exotic heavy metals and toxic byproducts needed for the lightweight photovoltaic cells usable on spacecraft.

Even if you had a lunar colony to produce the panels up there, you would still have a massive launch cost for the colony, everything it would take to be self sustaining, and you would still have an extremely limited production rate compared to earth itself. We are a long, long way from running out of the ability to take advantage of earth bound solar power. And by expanding earths energy capacity first, we open the option of reducing the long term cost of launching material into space by using active structures like rail guns, launch loops, space fountains or other methods.

[ed boy]

Also, why would it be necessary to send humans up there? The production and maintenance could be done using machines, be they automated or remotely-controlled. The cost of sending a machine to the moon is a lot less then sending a human to the moon, and the cost of keeping a robot there is minimal.

[Maggarg - Eater of chicke]

Someone had better finally work out nuclear fusion soon, dammit.

[redacted123]

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[DJ]

The cost of sending a machine to the moon is a lot less then sending a human to the moon, and the cost of keeping a robot there is minimal.

A machine that can perform every task a human can and weighs less than a human? I doubt it.

The point of sending humans is that they're so versatile.

[mainiac]

Even if you had a lunar colony to produce the panels up there, you would still have a massive launch cost for the colony, everything it would take to be self sustaining, and you would still have an extremely limited production rate compared to earth itself. We are a long, long way from running out of the ability to take advantage of earth bound solar power.

Not really.  Silicon is abundant on the moon (as on earth) so the thing that's holding you back is the energy costs of forging the crystals.  If you have that energy, then it's really easy to make solar panels.  And... the entire point of this is cheap energy.

And by expanding earths energy capacity first, we open the option of reducing the long term cost of launching material into space by using active structures like rail guns, launch loops, space fountains or other methods.

That is all assuming a technological breakthrough.  But the idea I outlined above is something that can be done with existing technology and not an iota more.  New technologies could certainly help, but they aren't needed.

[DJ]

Nope, like I already said we don't have biodomes technology yet, and it's a prerequisite for everything else.

[Maggarg - Eater of chicke]

Spess elevators also. We still need better carbon nanotubes though - something like three times better.


A biodome thing on the moon or mars might not actually be too hard, since to keep it up all it needs is to be full of air, thanks to the differences in pressure. Basically a smaller, sealed Eden Project - a geodesic dome of tough, flexible plastics.

[DJ]

The hard part is maintaining a stable ecosystem in one of those.

[mainiac]

Nope, like I already said we don't have biodomes technology yet, and it's a prerequisite for everything else.

What are you talking about, biodomes.  We have submarines that are capable of spending 30 years underwater if it weren't for lack of food.  But a space colony would be able to grow as much food as you need.  Where is the problem? 

It's not like this is supposed to be a completely closed system, you add materials from the outside as well as recycling what you have with plants.

[Nadaka]

Silicon is not the only component of high efficiency PV panels, the good ones are doped with rare heavy metals.

I am not assuming any significant technological breakthroughs. Solar thermal is a proven technology, frictionless magnetic bearings are well known, and theoretically we don't even need material stronger than steel.

You are assuming technological breakthroughs, even if you don't know it. In order to launch a self sufficient colony, either supporting a human population or with self replicating robotics, it would require a launch capacity that can not be achieved using conventional chemical rockets if we don't already have the energy production capacity on earth to hydrolyze water in massive amounts.

You are putting the cart before the horse. You can't get cheap energy from space until you have enough cheap energy on earth to make space accessible.

[DJ]

The problem is that you need to launch this submarine into space. And another 20 submarines for growing food. Metaphor aside, what I'm saying is that you'd need lots of heavy equipment to maintain atmosphere needed for both the residents and the gardens that feed them. And all this heavy equipment is just too much to launch. What we need is space gardens that maintain atmosphere by themselves, both for themselves and the residential areas, and we don't have that kind of technology yet.

[Maggarg - Eater of chicke]

The problem is that you need to launch this submarine into space. And another 20 submarines for growing food. Metaphor aside, what I'm saying is that you'd need lots of heavy equipment to maintain atmosphere needed for both the residents and the gardens that feed them. And all this heavy equipment is just too much to launch. What we need is space gardens that maintain atmosphere by themselves, both for themselves and the residential areas, and we don't have that kind of technology yet.

Let's strap six rockets to a nuclear submarine with the eden project strapped on and see where it goes from there.


(Probably badly)

[thobal]

The problem with BioSphere2 was that their ocean volume was too small compared to their soil volume. There is plenty of energy on the earth in the form of fission power, people are just unwilling to use it due to scaremongering. Also, nuclear rockets could easily loft massive payloads but again, the fear of a few thousand additional cancers prevents this.

We could also use lasers to launch large payloads but that would require levels of international cooperation that have yet to be achieved.


If someone would sink a few trillion dollars into it, the payoff would be immense and inside a relatively short time frame. It's a fairly low risk operation; the opportunity cost is just so high that it's politically unfeasible for even the wealthiest of nations.

That, and when the returns poured in from all the automation research and energy gains there would be economic upheaval such as the world has never seen. Basically, the world would have to choose between Star Trek and Feudalism II: The Lower Classes are All Superfluous(Also Spaceships) style societies.