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If you go through the math quantitatively, the angular momentum for the climbers requires a few newtons of force over the one-week travel time, and we do that easily with our many tons of material in the anchor and the counterweight. The additional angular momentum will eventually be recovered from that of the entire Earth.

The quantities really are tiny, but just to be complete, a climber going up pushes the entire elevator slightly to the east, causing it to lean. However, the ribbon recovers for the same reason that it stays up in the first place. Centripetal acceleration is acting on the counterweight pulling it outward, and the lost angular momentum is replaced very quickly (essentially as fast as it is lost). The ribbon will never lose enough angular momentum to even deflect a single degree, let alone fall. The extra angular momentum is stolen from the Earth's rotation ...

I can't believe so many people can still harbor such a wacky belief. Cheap? Making dozens or hundreds of huge space vehicles to build the orbital or even more distant and expensive facilities and go god knows where to get the materials is cheap? Cheaper than the Third World slaves, cut-rate earth installations, and cheap surface vessels we currently use? Cheaper than strip mining? Dude, what are you smoking, pass the fucking blunt!

Or perhaps you are referring only to gathering "energy" from space and bringing it to earth. Two possibilities (ignoring the expense of setting up the energy-gathering, concentration, and preparation for transport part):

• Package it up in physical containers and send them to earth. Expensive, doesn't sound practical, hard to believe it could be competitive with earth-generated energy, need to transport containers both ways.
• Beam it down in some way. Try playing Sim City some day, and use their orbital microwave power stations. If you think that's not how it would be in real life, then I truly hope you are the kind of person who never votes in elections. Also, it would be very expensive.

Where, in the space vehicle? In the stationary space facilities? They look pretty cramped and uncomfortable to me. Shit, I'll take boring old suburbia over living in a large tin can any day.

all i need is a cheap way to get there.

Yeah. Ain't thermodynamics and elementary physics a bitch?

i hear that the space elevator is a cheap way to lift mass into space, that clearly makes sense.

Yeah, and I hear that by running up half-trillion dollar deficits and giving half-trillion dollar tax cuts to wealthy people, we will soon be rolling in prosperity. A space elevator will be the most expensive single engineering project ever undertaken by mankind. And for what? What will it be used for? What will be the amortized cost per trip or cost per kg? Not exactly cheap, I'll wager.

and because of wind friction, the elevator will generate 'tons' of 'clean' electrical energy. hell, that alone is worth the endevor.

Damn, I almost wish I were that gullible. Yes, I've read the spiel, but I'm not buying it. I get the distinct impression that they are underestimating the stresses and hazards, and overestimating their as yet non-existent materials. This sounds more like a pie-in-the-sky scam than a realistic project.

But, just cuz I'm a nice guy, let's just pretend for a moment that I am wrong. An earth-to-space elevator is still a dumb idea. The first space elevator should be built on a) a smaller celestial body, with b) no atmosphere, and c) with few liabilities and possible damage to people and property as possible in case of catastrophic failure.

Yes, that would mean the Moon.

2. What if [the ribbon] breaks?

The majority, the long end out in space, gains enough speed that it burns up in the atmosphere, with the lower portion falling into the sea. It will not fall on top of anyone.

3. For the portion that doesn't burn up in a fall- what effect will it have on the environment?

Honestly, it will make a little bit of a mess. But New York City tickertape parades have made bigger messes. Comparatively it will put much less dust, dirt, debris and chemicals into the environment than
wildfires of the American west, any one of the large expendable rockets, or a month of natural meteors hitting Earth. The ribbon is light (7.5 kg/km) so, any pieces that fall to earth will slow down, in the air, to about the same terminal velocity as that of an open newspaper page falling. It will not have enough momentum to cause mechanical damage when it comes down. We have considered other health risks such as inhalation of very small fragments and believe this will not be a problem but we are conducting studies to make sure this isn't a problem. Since we are aware of the possible problems now we can design the elevator to avoid these problems.

There are all sorts of industry statistics gathered that simply aren't convenient for the particular industry. The fact that this number doesn't seem to be around seems to me to be a disqualifier. You can't claim that the number of trees is bogus and the real measure is standing board feet when standing board feet numbers aren't kept by anybody and are thus unmeasurable.

Like so many environmentalist scare stories/statistics, it evaporates on closer inspection. I'm a fair guy and would be willing to change my mind with actual evidence but this is just unacceptably weak to be designated evidence.

Now on space resource extraction, you're quite correct that rockets don't have it in them to reduce orbital costs to a level that would realistically provide for space resource extraction. I'd suggest you look up The Fountains of Paradise instead of 2001 for a better inspiration. The space elevator described there has been used as an engineering exercise by many, many people and it's pretty well thought out, only needing the right material to be discovered.

That material, single walled carbon nanotubes, was first discovered in a lab in 1991 (I believe in Japan). In the past year, they've gone from tiny fibers that you need a microscope to see to visible fibers measured in centimeters and from fiber expoxy concentrations of lumpy 1-5% nanotubes to an evenly spread concentration of 60% that can be created in unlimited spools. Now it's possible that we went from 5% to 60% and never go further, we'll never get to the 90% level that's going to be strong enough to actually make that elevator.

Considering the astonishing progress made in the last year (both in manufacturing and reducing the price to manufacture), a great deal of it in the last 6 months, you will forgive me for not quenching my optimism in dark negativism.

An elevator company is already organized and working on developing all the necessary technology to make the elevator a reality and which will put lift prices at the $100-200/kg range, an area which will permit the lofting of microwave beaming solar power satellites, mining, and factory tools. Obviously, getting things down is much cheaper that lifting because all you have is a braking problem.

The biggest problem will be a huge shortage of capital followed by the problem of massive dislocation of economies. It'll also bring a cleaner environment while enhancing everybody's standard of living.

Disruptive technologies like the elevator (and it's somewhat more expensive cousin, the railgun launch system) happen more and more often as population rises and more 'one in a million' geniuses exist simultaneously. I'm mindful of the lesson of Henri Coanda who, in 1910, flew the world's first jet airplane (the jet engine depends on the Coanda principle). A lack of capital and freedom drove him to Paris from his native Romania and he never did gather the funds to bring us to the jet age. A lack of capital, a lack of economic growth means more ideas than necessary will die stillborn.

That's what really frustrates me about social redistribution programs and punitive solutions to pollution problems, they tend to stifle economic growth and capital formation. We're going to need every $ we can get to manage the transition that's coming, both out of oil (which big oil has signalled by being quite happy with GWB's push for hydrogen) and into space resource extraction, generation, and manufacturing.

Actually, now that I think about it, Highlift Systems, from my understanding, was a precursor to a new company called LiftPort, so that's probably a better link.

On the other hand, Liftport has raised a million bucks in half the time they expected, and the gonzo attitude appeals to my Heinlein-educated sensibilities. I sent them a few hundred bucks yesterday, just in case.

We got a chance to chat with Michael Laine of LiftPort at this year's National Space Society annual meeting just a couple of weeks ago. They're looking for small investors already - talk to them if you would like to be involved at all. They will also have a private venture funding round coming up for larger investors, but anybody with a few hundred dollars could get involved at this stage (I think the deadline is June 20).

These guys are looking for 180,000 KM of the stuff, I wonder can the get it here.

Oh and the need a big rock to tie it to as well....

I hope they have a good relationship with Highlift Systems, because their FAQ is a copy of Highlift's .