Could it actually happen?

23 09 2008

I couldn’t believe it when I heard it.  The technology is almost there, and perhaps less than a decade of focused research is needed to make it into reality.  The cost is surprisingly low, as far as national projects are concerned.  Kudos to Japan, the economic and scientific benefits will be absolutely limitless.

I’ve blogged on this before, but I never thought the US would have the political willpower to do something so bold.  I did not expect that another country would either, but I am pleasantly surprised that there is actually a movement afoot to do this.  It’s obviously still no where near an approved project, but the fact that people are seriously thinking about this means a lot.  Maybe I’ll see it in my lifetime after all.

More on the space elevator

16 06 2008

Is the Space Elevator Feasible?

The question that many people have is whether a space elevator is simply a product of overactive imaginations from the Sci-Fi world, or is it an engineering possibility? For people unfamiliar with the idea, the notion of a 36000-mile elevator seems fantastic and ridiculous. Nevertheless, if you analyze the problem, the idea turns into something that is manifestly possible.

First things first – what exactly is the space elevator? For once, the name pretty much describes exactly what it is. It consists of an extremely strong thread of material going from the geosynchronous orbit to a spot near the equator on earth. Alternatively, if you don’t want to go all the way to the geosynchronous orbit, you need a counterweight at the top to keep the thread tight.

Once you have that, you can use simple electrical power (costing maybe $100/lb) to transport supplies (and people) all the way up into orbit. And really, most of that power could be recovered on the way down. It would be almost cheap – as cheap as airline tickets, to go to space. There will always be a price limit imposed by conventional rocket fuel – and there will not be commercial or private exploitation of space at any great level until something like a space elevator emerges.

But back to the elevator – is it possible? Obviously, the material in the thread would have to be exceptionally strong to withhold the pressures imposed on it, not to mention withstand weather patterns and other forces. Until very recently, such a material did not exist. Diamond could possibly have done it (but it would have very low capacity), and the price of a 36000 thread of diamond would be prohibitive.

The answer is [almost] carbon nanotubes. Carbon nanotubes are not quite there yet in terms of the strength required, but they are rapidly going there. The total cost of the space elevator, at $5 billion to $20 billion may sound like a lot, but it is actually not prohibitive, considering the costs of other things in space. We’re wasting millions of dollars on frivolous technologies, and this has the possibility of completely revolutionizing our society. Imagine a cheap, easy way to reach space. Everything follows from that point, from the mining of asteroids to permanent colonization of space. We wouldn’t need to build space ships that are pretty much huge fuel tanks with a small tip with a couple people sitting on top.