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Space Elevator May Become Reality
mojotek writes: "The NASA Institute for Advanced Concepts has a study(15Mb pdf) about the feasibility of a "Space Elevator" comprised of a 22,000 mile long cable built out of carbon nanotubes. In theory, it would be able to carry loads of 20 tons to space without using a single rocket engine. Sounded way too sci-fi for my taste at first, but this article at TechTV actually helped fill in the holes."
Not to dismiss the elevator out of hand, but wouldn't research into efficient space vehicle propulsion yield better long term results? While the engineering feat of building an elevator would certainly yield advances in science and technology, the elevator's limit would be its height. Non-tethered vehicles have no such limit.
But the weight to payload ratio sucks pretty hard. I imagine the up-front construction costs would be a lot higher than the cost of building rockets. So even if it's cheaper after, say, 10,000 uses, we might not see anyone wanting to build it.
You see? You see? Your stupid minds! Stupid! Stupid!
No, you don't need a counterweight. If the cable is long enough so that the center of mass is in geostationary orbit it will just hang there by itself.
Thats a good idea, but... How do you purpose to keep the platform suspended? Is it hanging "off" the satelite? If so, won't its weight drag the satelite into a lower orbit, eventually destroying it? Or is the satelite going to be continuously firing retro-rockets, which would need enormous amounts of fuel, thereby negating the purpose of the elevator? Not to mention the wind blowing said platform around.
People go nuts when you suggest building a new nuclear reactor. What do you think would happen if you tell them you're going to multiply the potential destructive consequences of that by many fold, and suspend it over their heads? And the potential for an accident pales in insignificance if you consider how attractive a target it would make for someone to take down on purpose. I'm as big a techno-freak as anyone (hey, bring on those nukes, we need the power), but this would worry even me.
Basic probability states that something not happening for a while doesn't make it any more likely to happen in the future. Close only counts in horseshoes*.
* (Well, it counts in a few other things, too)
"For success, it is essential you have Thunderball Fists." "I can have such a thing?" "That's right. Thunderball Fists."
No, really. While we're building a 22,000 mile long cable strong enough to hold 20 tons, where are we going to put it? It's probably too big to actually
We can't start stringing it off into space as we build it, because it'd keep tending to fall back towards earth until it were about.
And, once we've figured out all that, how do we get it
That said, it'd be a damn cool thing if we had it, and if a team ever succeeds in constructing one, I'll personally buy a beer for every member of the project.
Gimme a break. How do you prevent terrorists from suicide bombing the Space Shuttle? The Superbowl? Nuclear plants? The [fill in your favorite target]? It's all about security, and in the end, about acceptable risk. You can't completely eliminate all threats, just minimize them. Letting fear of a terrorist attack getting in the way of projects like this is letting the terrorists win.
MSN 8: Now Microsoft even has bugs in their ad campaigns.
It doesn't drop off exponentially, it drops off as the inverse square. This is an awful lot different from exponential. The universe would be much different if the force of gravity was proportional to e^(-r) ;)