Happy New Year!
Ok, enough pleasantries, let's get down to business. Obviously, if you're a regular reader of this site, you're familiar with the concepts of "Space Habitats" like Babylon 5 et al. (And if you're not, here's a quick review: http://en.wikipedia.org/wiki/Space_habitat )
As cool as trips to and colonies on the other planets and moons in our solar system may be, such habitats offer the best and safest hope of actually colonizing space. As much as I enjoy space exploration itself, Colonization is really a vastly more important goal, and the one that will have really long-ranging and profound effects on humanity and human civilization. Unfortunately, no spacefaring nation has ever even vaguely advocated this as a national goal, though the US has done several intensive studies of the idea, and I presume the Soviets did so as well. The most obvious and probably safest area to build one of these beasties would be in one of the LaGrange points ( http://en.wikipedia.org/wiki/LaGrange_point ), ideally either L4 or L5, as they're the most stable. (L1 is semi-stable, L2 & L3 are stable on only 1 axis)
The main US study was done in 1975, and remains the high-water mark of NASA actualy thinking big and heroically. There was a suplemental study done on actual construction methods and such in 1977, but the bulk of the work was done in '75. I've read every paper I can find in english on the subject, as well as the results of the '75 study themselves, and it appears that pretty much everyone who's discussed the subject uses that NASA paper as the baseline. There's differences in details, timeline, construction methods, etc, but pretty much *everything* I've read on the subject still follows the basic '75 outline.
So here's what they felt was involved in building a permanent, self-sustaining LaGrange colony with a population of 10,000 people:
1) Get a working space shuttle system (they anticipated this for 1977 or 78)
2) Launch an average of 50 shuttle flights a year. Really! (They'd estimated a fleet of about 12 shuttles)
3) Build a space station in orbit
4) Build inter-orbital tugboat spacecraft that can haul people and supplies from Low Earth Orbit (LEO) to L5 and Lunar orbit. Launch them on shuttles, and dock them at the Space Station.
5) Build Lunar Landers (Probably modified Inter-Orbital Tugboats), and launch them in shuttles. Use them to ferry stuff from Lunar Orbit to the surface and vice versa.
6) Build *Another* space station in the L5 point to serve as a construction shack for workers building the station.
7) Build a moonbase with an average-sized crew of 200 people.
8) Build a mass-driver to throw ore from the moon into lunar orbit at a rate of 1.1 Mt/year.
9) Build *Yet Another* space station to CATCH the 1.1 megatons of rock hurled into lunar orbit.
10) Build two huge nuclear powered ore-carrier spacecraft to haul the rock from lunar orbit to L5.
11) Replace your crappy 1st generation space shuttle with a much larger and more efficient "Second Generation" shuttle around 1990.
12) Continue an average of 50 shuttle launches a year.
13) Build a factory in L5 to convert ore to metal and glass and air and stuff, as well as producing Solar Power Satellites for energy.
14) Actually build the damn LaGrange Colony, finally.
15) continue to produce Solar Power Satelites as economic justification for the colony itself, and export cheap, clean electricity to earth as a 'cash crop'
16) begin construction of a 2nd colony.
Obviously an amazingly daunting task. The 1975 study assumed that @ a rate of 50 launches a year in perpetuity, with the introduction of a better shuttle 1 decade into construction, and the *likely* development of some additional launch vehicle besides, and assuming *Nothing* went wrong (Either actual disasters, or a loss of political support), we'd be looking at a construction schedule of about 25 years. That was based on anticipated performance stats for the shuttle *before* it went into service, and *before* the carter administration slashed the program down to the mere caretaker shuttle schedule we saw in the 80s. Now that we actually know what the Columbia class shuttles are capable of, I'd estimate construction to take between 50 and 75 years, and that *With* the complete support a superpower to back the project to fruition.
Obviously, that's unacceptable, and just as obviously that's why neither NASA nor any administration since 1975 have backed the plan: it's simply too ambitious and too long term.
Some years back, I toyed with the idea of a book taking the form of an autobiography of someone about my age who grew up in a world where the US started building an L5 colony program around 1981 or so, concurrent with the shuttle program itself starting. It'd be a paralell history, of course. After 25 years of intensive construction, the thing was still only half complete. The punchline was that the Russians, meanwhile, had built a Bernal Sphere ( http://en.wikipedia.org/wiki/Bernal_sphere ) on the ground in Siberia, and launched it into orbit all in one piece, with the crew aboard using a Nuclear Pulse Rocket ( http://www.astronautix.com/articles/probirth.htm and http://en.wikipedia.org/wiki/Nuclear_pulse_propulsion ) and that was the end of the book, really. As with all my books, it never really went anywhere.
It kept nagging at me, though: there just had to be a better way, a more efficient way, that didn't involve 3 space stations, a moonbase, a shuttle program, and fanatical support of a superpower. I toyed with the idea of simply launching a colony all at once, as per my story idea, and using that as a seed to build other colonies from. All well and good, of course, but you *still* need all that other crap to build your colonies, even if you start out with a fully operational one: you still need the mass driver, the catcher station, a way-station for astronauts, tugs, a moonbase for mining operations, and those damn huge-and-messy-and-inefficient ore carriers (Only 80% of the mined ore actually makes it to the construction site, btw). Eventually, I decided the problem was that I was looking at it from the point of view of a modern industrial society, approaching the whole concept like it was a massive government program like Apollo or the TVA ( http://en.wikipedia.org/wiki/Tennessee_Valley_Authority ) or what have you.I decided that I needed to take a more 'polyneian' approach to the problem: set off on boats with your entire town, and hope to Pele that you find land before you run out of food and water. I promptly forgot all about it.
My subconsious didn't, however, because yesterday I had my big "Monkey-touching-the-monolith" moment: You don't build a Bernal Sphere or whatever on the ground and shoot it to L5, you build a *moonbase* on the ground and shoot it to the moon! Construction is vastly simpler, and there's much less dead space that you can pack full of supplies and animals and equipment and people and whatnot. Here's my simplified version of the plan:
1) Build Moonbase Alpha on the ground in some place like Siberia, the Gobi Desert, the Sahara, or Antarctica.
2) Launch it on a huge NPR
3) Land it on the moon (this is, I admit, the really tricky part. On the bright side, however, the station already has huge shock absorbers on the bottom of it. )
4) Mine ore and process it in a factory *on the moon itself* rather than shooting it to L2.
5) Build a colony on the lunar surface.
6) Launch the colony to L5 or L4 using yet another Nuclear Pulse Rocket
7) Lather, rince, repeat.
That's 8 steps less than the NASA model, and an order of magnitude easier and cheaper - we've eliminated all 3 space stations and the ore carriers; building stuff in gravity is about 7x easier than 0-g construction (Which is just a superbitch to do), and launching a complicated and heavy structure from the lower-gravity environment of the moon, w/out having to contend with atmospheric resistance is *vastly* simpler. Best of all, it can be done w/out any continued support from earth if you need to.
So that's the idea. Whadya' think?