or a new bold plan

So I've poopoo-ed the moon base plan, the question could be asked if I have a better idea.

I've got an idea. A project that would be a worthy successor to the Apollo program. A plan that would require a program of scientific research, technological development, and incidentally encourage the beginning of a revolution in material science.

I'm talking about building a space elevator. For some background on what I'm talking about you can read this wikipedia entry. It's recently occurred to me as an ultimate answer. I'm unhappy about the current moon plans on many levels. I'm unhappy that after decades of talk about developing a better reusable launch vehicle system, including the holy grail of launch vehicles, the single stage to orbit concept, we've abandoned ALL of the plans we'd come up with to fall back on Apollo era technology. Instead of it being a new mission to a new frontier that would require us to develop new technology, we're going back to where we've already gone, using technology we've already established.

But a space elevator would be a different matter. Perhaps the concept lacks the easy popular appeal of walking on the moon, but it WOULD be that combination of a bold development of new technology to give us new capabilities. And this is exactly the right time for it. We're currently poised on the edge of a new era in the world of materials sciences. I'm talking about carbon nanotechnology. In this case, specifically carbon nanotubes. Much like the state of rocket science at the start of the Apollo project, we already have some capability to make carbon nanotubes and are starting to work on ways to use them. But it needs more work, more development.

An often under-appreciated benefit of the Apollo program was the many technologies developed for it that found applications in everyday life here on Earth. All too often these programs are viewed as isolated, expensive projects with no practical value. I can't say I don't understand why, we take our technology for granted. If someone's life has been saved by surgery made possible by magnetic resonance imaging or a CAT scan there's no reason they should know that both of those technologies are offshoots of NASA programs. The cheap quartz clocks that are the basis for the computers that run our world? Thank NASA.

When you undergo a program of intensive scientific and technical research even your failures can produce useful technology.

In the case of a space elevator even the expected technological developments are revolutionary. As I've already mentioned, a key component of the entire program would be carbon nanotubes. To put it simply, as I've already stated, I believe carbon nanotubes will usher in the next material revolution. They behave differently than metal, so I'm not sure it's completely accurate to simply compare tensile strength of nanotubes and various metal alloys, but the numbers themselves are astounding. The listing I referenced lists high carbon steel as having a tensile strength of 1.2GPa, whereas a multi walled nanotube has tested to 63GPa, and can theoretically get up to 140-177GPa.



Imagine the side effects of a program that develops better methods of manufacturing and using such a remarkable material. Again, it behaves differently than metal, you can't just replace a metal structural component with a CNT version, but with suitably altered design techniques it should be possible to make things far lighter and yet still far stronger than ever before. Already the far cruder carbonfiber composite material has made a massive impact in everything from aircraft design to artificial limb construction.

But carbon nanotubes have potential nanotechnology applications. I have seen reports of research still underway that involved using either nanotubes or a similar carbon structure, this time round instead of tubular, the buckyball, in various advanced solar power concepts, either for generating electricity more efficiently than we can now or else in using sunlight to split water into hydrogen and oxygen, thus providing a renewable source of hydrogen fuel cell fuel.

It's a new era and we've only glimpsed the potential that the nanoscale carbon structures offer.



But about the space elevator itself. As I said, it doesn't quite have the same traditional romance of a manned base on the moon, but it's still a classic science fiction concept that should appeal to the masses once they understand what it would mean.

A brief trip through google found estimates of the current cost to launch payloads to orbit of at least 15,000 dollars per pound.

Compare that to the rock bottom estimate I've seen for a space elevator of $100 per pound. That's the lowest estimate, they go higher, but clearly they're in another realm altogether compared to traditional rocket transportation.

Imagine that that kind of reduction in cost would mean. Imagine NASA's budget effectively being multiplied many times. Imagine them sending out ten times as many space probes, or else significantly larger and more capable units.


Imagine space tourism reduced to a point where it might cost as much to go BEYOND low Earth orbit (by its nature a space elevator would have to at least go beyond the much higher geostationary orbit) as it would to buy a first class ticket to Japan.

This would not be instantly achieved.. when the first elevator was completed there'd be fierce competition to use it, the limited capacity would be likely to drive the price significantly up if it were run on pure market forces. But once one was up it should serve to drastically reduce the cost of any subsequent elevators. An initial elevator that proved itself useful could find itself almost instantly pressed into service lifting payloads for constructing further elevators.

There are a number of unique benefits that I never even guessed at until I read the wikipedia listing that I referenced. The most striking is that, through a physical mechanism that I don't wish to get into detail here (but which the writers of the article did elaborate on), a space elevator would be used as a catapult. It would be possible to fling a payload out of Earth orbit without actually using any rocket power at all. Combine that with additional rocket power and vehicles could be sent to outer solar system targets far faster than they can now.

And obviously such capability would enable a manned mission to Mars to be made better and cheaper. Imagine sending ten times as much hardware on the trip. How much additional capability could the mission gain?


There are potential problems, of course. The most significant is the statistical guarantee that
any single fixed site elevator will eventually be hit by a satellite or piece of space junk, and the unpleasant likelyhood that that would result in the cable being severed. Imagine a billion dollar structure being completely destroyed as a result of a single collision. Not only that, but the counterweight on the end of the cable would be flung into space unless it were fitted with braking thrusters to allow it to remain in Earth orbit.

It would be a tempting target in any military conflict. I'm tired of what is rapidly becoming a cliche, but there's no way to avoid that it would be a tempting terrorism target as well. The first space elevator would be a high profile target like nothing else in the world.

But these are problems with possible solutions. If we had been willing to turn back from the path of the Apollo program because of possible problems we'd have never bothered. We don't do these things because they're safe or easy. We do them to advance our knowledge, our capability, and indeed ourselves.


We're approaching the end of the era of the Space Shuttle. I'm terrifically disappointed in some aspects of the Space Shuttle program. It was supposed to be more capable and far cheaper than previous disposable launcher systems. There's no denying its capability, but in the cost arena it was a spectacular failure. A single Space Shuttle launch costs about as much as Russia's entire space program budget for a year.
I'll be sad to see the retirement of the Space Shuttle. I have a great emotional attachment to it, it's an incredible symbol of the American space program.

It may be that the Ares launch vehicle system currently being planned would be more efficient than the Space Shuttle program.. but it's hardly revolutionary. It's an Apollo era throwback, an echo of what we had accomplished with the Saturn V. It's less effective because the heavy lift version, the Ares V, is not "man rated", which means it's not supposed to carry people. So any manned mission would require an Ares, and anything heavier than the Apollo Command Module style Orion spacecraft (an overly pretty name for a vehicle with such little capability) would also require an Ares V. Two separate launches for what Apollo managed with just one. It's supposed to be a reduced cost system, but I don't see that happening when any serious mission requires a pair of launches.

Really, compare the options. A revolutionary launch mechanism that cuts the cost to orbit by a factor potentially as high as 100 times, ushering in a new era of space exploration (including, why not, a moon base, a launch mechanism that cheap would make a moon base much cheaper to operate as well) as well as in material science, or a conservative launch vehicle that would require two launches for any single moon mission, and otherwise leave us with less capability than what we currently possess with the Space Shuttle.

I don't disagree with the people pushing the moon and Mars plans in that I think it IS time for a new mission, a major program to push our scientific and technical understanding to the limits and beyond. I just don't think a moon base using decades old technology is anything resembling that. It looks to me to be a tired attempt to gather the interest of a fickle public grown bored with the ISS. Well guess what? We got tired of the moon before as well. The Apollo program wasn't canceled because we'd done everything there was to do, it was canceled because, despite the ever increasing quality of television broadcasts that it was providing (live video from the moon, even in today's era of live TV from the ISS that still amazes me), people weren't watching.

I just don't see the wisdom in trying to plan a space program based on its ability to compete with soap operas and sitcoms.