Kim Stanley Robinson's MARS books prove to be prophetic

Cafe Society
1

If anybody’s read the MARS books by Kim Stanely Robinson, you may remember

the elevators that went from the surface of Mars to its satellites

Well, apparently these are in the works for Earth.

OK, so Arthur C. Clarke thought of it first, but I get the impression he advocated their construction and didn’t really detail their use like KSR did. The article even mentions the possibility of terrorist attacks, as KSR so described in his books.

One thing, though: don’t satellites orbit around Earth’s equator? This would mean the elevators would have to be built in South America, Africa and Indonesia. Right smack dab in the jungles. Environmental Impact fallout issues, anyone?

2

Did you see the price tag and target dates? $6Billion and done in 15 years. No bloody way. Don’t get me wrong I’d love to see one work but it’s not going to happen just right now.

Objections

  1. Sufficiently long carbon fibres have yet to be built
  2. Spinning of long carbon fibres into a lifting fabric yet to be done
  3. Testing of lifting fabric, yet to be done
  4. Sea based platform (to avoid getting a nation’s approval) yet to be done
  5. Multinational approval to have an x thousand km long ribbon that could (but wouldn’t) smash across various countries if it fell.
  6. Lifting mechanism and their redundancies
  7. Energy source to power lifting mechanisms
    It’s no simple feat and it’s going to require lots and lots of testing. Hell it takes years to build an airport (and we’ve done that before), what make us think we can just slap a space elevator together?
3

$6 Billion does sound suspiciously cheap for such an undertaking.

Location doesn’t seem like a big problem; put it in the summit of one of the Andes. Therefore, not in the jungle, Knowed Out. Robinson’s elevator was on the summit of a Martian shield volcano, remember.

I’m reminded of the most spectacular scene in Robinson’s series, where

The elevator cable crashed, wrapping itself around the Martian equator several times and disrupting the terraforming process for years.

I guess that would be a concern for an Earth-based elevator as well.

4

Damn. I was hoping to hear that somebody had built a Super-Rathje.

5

Well the ribbon is suppose to be 1 m wide :dubious: and certainly less than that thick. The thing should breakup and burn when entering the atmosphere.

6

Arthur C. Clarke did more than merely advocate the building of a space elevator. He described their construction (in no small detail) in his novel The Fountains of Paradise. This was better than Robinson, IMHO, who only described its destruction. BTW, the ending of The Fountains of Paradise showed a construction project of even greater magnitude.

7

But Olympus Mons (the one they built from IIRC) is ridiculously higher than any earth based mountain. Also, the atmosphere is thinner on Mars and the gravity is weaker. I believe that this would make it easier to build on Mars. (Except for the fact that it is hard to get to Mars at all).

8

6 billion is actually the number of threads on space elevators on the SDMB. That’s the only relation the number has to reality. 60 billion won’t do it either.

And you absolutely cannot give Stan Robinson any credit for this concept. He is a wonderful writer, but his Ph.D. is in English. If he wrote about a space elevator, he learned everything about it from the real physicists in the field.

That would include the late Dr. Charles Sheffield, who was a working physicist and whose book, The Web Between the Stars, independently written and published at almost exactly the same time as Clarke’s Fountains of Paradise also described the workings of a space elevator. He probably, quietly, did even more work than Clarke on the subject, although Clarke is the publicist supreme.

Many other writers have toyed with the concept since (hell, I snuck in a mention of it in the novel I’m writing now). It’s so incredibly useful that people will continue to talk about non-stop.

But you’ll notice that in the article the OP linked to, not a single practical word is spoken. There will be 6 billion more similar articles written before the first payload is lifted into space.

9

You see, if Robinson’s elevator had been sabotaged near the bottom, it would mostly have fallen upwards; only the bit below the break falls to Earth (or Mars as the case may be.)

SF worldbuilding at
http://www.orionsarm.com/main.html

10

Cool, I didn’t realize how much research Robinson must have put into his book. He named the town around the “socket” (where the cable attached to the ground) Sheffield.

I wonder how many other little references he has in the books - since the level of detail is astounding.

11

He spent years doing research, Waenara. He read every book by Michael Carr and every other Mars scientist, for example. Subscribed to journals. Read all the relevant fiction. He probably knows more about Mars than any other layman.

12

Only number 1 there is really significant. Once you’ve got the fibers, it’s easy to make a cable out of them, and once you have the cable, it’s even easier to test it. Sea-based platforms are already done all over the place, and why would you avoid getting a nation’s approval? Any nation would love to get the tax money this thing would pull in (but there are still good reasons for putting it out at sea). I’m not sure what’s so mysterious about the lifting mechanism: You have rollers gripping the cable. Likewise, the power is straightforward: You have a normal coal-fired power plant at the bottom, and beam the power up to the lifters by maser.

Which still leaves that number one objection, that we don’t yet have long nanofibers. But we will. Even without a space elevator, that stuff is just too potentially practical and useful to be ignored. Think of what it would do for suspension bridges and skyscrapers. For that matter, think what it would do for golf clubs and fishing line. Any engineering problem will eventually be solved, if you throw enough time, money, and effort at it, and the terrestrial applications alone of nanofiber are enough to justify that time, money, and effort.

13

There’s probably some element here I don’t get, but how would you build an elevator to something that’s not in a geosynchronous orbit? The moon would be damn near impossible, let alone Mars, Venus, or the asteroids. (Wait a minute, I think I’ m seeing the light while I’m writing this - is the elevator simply a way to circumvent the whole ‘escape velocity’ thing from Earth’s atmosphere, after which you can simply use space shuttles without having to propell them into space?)

14

You got it, Short Guy.

15

Right, Short Guy; and when you have an object at the far end of the space elevator, you can just release it at the right time of day for the object to be pointing at its destination (Mars, the Moon, an L5 city, whatever) and you’ll get the first 1038+ mph* of thrust for free.

*Earth’s rotational velocity at the Equator; the “+” is for the fact that at the height of a geosynchronous orbit, it’d be a lot more.

16

Not only do we need sufficiently long nanofibers, but we’re going to have to have things built with them, first, to prove the concept to everyone’s satisfaction. To date, while minuscule fibers have been created, no structure has ever been built with them. So we’ll first need to see a suspension bridge/skyscraper (or, more likely, at least dozens and dozens) designed and built with the nanofibers to prove that it can be done (and you know that each one of those projects will take at least ten years), that the industrial capacity is there, etc., then we have to build the weaving machines (aren’t automated robots supposed to climb up and down the early strands in order to build the bridge?), when we still don’t have a single robot in existence that can build something outside of a factory setting (else, we’d see automated highway construction, at least).

I don’t see it even being reasonably possible this century.

17

They’ll have to be designed with the nanofibers too? What, are you thinking of some sort of nanofiber drafting pencil?

18

The elevator from the Moon’s surface could only really go to the Earth-Moon LI point;
Venus wouldnt really have a good position for this kind of space elevator, although there are about a dozen other kinds including -rotating tethers, loftstrom loops, rotavators and dynamic orbtal rings- which would work there.

All these types of equipment need buckyfibre to be as strong as the theoretical limit, although some rely on magnetic fields which are perhaps unfeasibly strong.
And I am not expecting any of them (except perhaps rotating tethers) in the next 100 years or so.

19

can this be done?

20

OK, so we build a suspension bridge or ten first. I can handle that. We’ll still have an elevator eventually. And I think that by “designed with nanofibers”, toadspittle means that they’ll have to be designed with nanofibers in mind: You can’t just take an existing design and replace the steel with carbon. The climbers, though, aren’t too high-tech: It’s a little car with a spool on it. They don’t need to be robotic: A robot has to respond to stimuli in some way, whereas a climber is always going to be doing the same thing.

As for launching from one, it’s not just your first thousand miles an hour that’s free. The further you go out, the more advantage you gain, and if you make your elevator long enough, you can get up to escape speed from the Solar System. Which means you can go as far as you like for free. You’ll still need some rockets, most likely, to change the plane of your orbit (unless your destination happens to be in the plane of the Earth’s equator), but almost all of your energy requirements are taken care of.

There are a variety of related technologies, which would be useful for getting around the Solar System. Space elevators are good for getting anywhere that rotates fast enough: They’d definitely work for Earth and Mars, and I’m pretty sure also for the major outer moons (Io, Europa, Ganeymede, Callisto, Titan, Miranda, Triton), but not for Mercury, Venus, or the Earth’s moon. Anywhere in vacuum, you can use a skyhook, a rotating cable with a counterweight at one end, with the rotation timed so that it’s momentarily at rest when the end touches a planetary surface. You’d lose too much energy if you were dipping into an atmosphere, but they’ll work fine for Mercury, Luna, or the asteroids. That pretty much just leaves Venus and the gas giant planets themselves, but who wants to go there, anyway?

As for power beaming, there have been experiments with unmanned aircraft powered by microwave from the ground. The technology isn’t yet mature, but it’s probably closer than large-scale nanofibers.