Is there any good reason why this wouldn't work?

Is there any good reason why this wouldn't work?

I want to run for office in a decade on a pretty bland populist platform, and want the space elevator to set me apart.

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what-if.xkcd.com/94/
en.wikipedia.org/wiki/International_Space_Station#Threat_of_orbital_debris
en.wikipedia.org/wiki/Mass_concentration_(astronomy)
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it works on paper. the build challenge is finding a light enough material with the strength needed.

carbon nanotube or graphmeme can do it. yet if you place one atom wrong, you lose significant strength. after so many wrong atoms the whole thing is useless.

you have to place it on the equator. South America is the only place stable and secure enough to put it. Africa and SEAsia, not so much. Pacific Islands are out because none are big enough.

How much payoff is there if you can only run one climber at a time? And how much more efficient will the climber be than a traditional rocket?

>any good reason why this wouldn't work

Orbital debris will cut the cable.

A space elevator would be under enormous tension and would need to be almost atomically precise across its entire length in order to be strong enough. A fleck of paint or grain of sand moving at low Earth orbit speeds would hit with a relative velocity of nearly 7 kilometers per second, and cause significant damage to the cable. The damaged cable would not be able to handle the tension forces and therefore would snap.

The only options are to either overbuild the cable by a ridiculous amount, making it way thicker and heavier than necessary, and thus making it much more expensive and difficult to build, or you could attempt to track every piece of orbiting material larger than microscopic and use some kind of active defense system to vaporize the debris before it impacts the cable. Both are pretty bad options, but you can't go ignoring the problem and having your cable be cut after a few weeks or months of it being up, every time you put it up, if you're lucky.

Space elevators only really make any sense aroudn very small worlds with low gravity and a fast spin, needing only a short cable and not requiring ultra-strong materials (although we'd use them anyway just for the margin they provide, because space debris would still be a problem there as well).

because if you run it for decades, the cost per pound is significantly reduced versus rockets.

you can also put things up when ever instead of waiting for a window.

just put lasers on the cable and you can vaporise or deorbit space junk. in fact it can be a intended function of the elevator, to clear space of debris.

Efficiency depends mostly on how power is being generated on the climber, although fuel costs are such a small factor in the cost of launching a rocket that it makes it mostly irrelevant anyway. The theoretical cost savings of a space elevator come from the fact that no parts of it are thrown away during operation. Reusable rockets would be able to achieve almost as low a price point per kilogram payload as a space elevator, except reusable rockets don't require a massive initial investment and there is no single massive point of failure.

Ideally a space elevator would have something like a dozen cables and climbers all operating constantly. However even with multiple climbers the problem of trip times would be hard to solve; Imagine trying to make an elevator that can climb a cable against gravity for ~38,000 km, and trying to reduce that trip time to 48 hours. That'd require a vehicle climbing continuously at 792 km/h, just slightly over half the speed of sound, and slightly under the cruising speed of a jet airliner. Straight up. A more achievable top speed of around 200 km/h results in a trip time of around 8 days. A space elevator is probably not something a person would want to take a ride on.

>just put lasers on the cable

That adds mass per unit length of cable, it may not be possible to watch for debris that small, how do we power those lasers, etc etc. Not to mention designing the lasers so that a climber passing at 200+ km/h doesn't strike and destroy them.

>Is there any good reason why this wouldn't work?

Because magic does not exist. It is a total pipe dream for Earth. You can do it on other celestial bodies with very low g, though it may or may not be worth doing on those.

what-if.xkcd.com/94/

8 day trip to space with food water and shelter and toilet would be bad?

I'd do it with minimal rations, assuming it's proven and safe.

the mere fact that you would need to uproot all the remaining trees to make enough rope to be able to get that high and have the bulk required to not snap with the slightest change in force.
Then you have to fly a rocket in such a way that relative to the earth it moves direcly vertically (an impossiblity to do)
Then you have to ensure no space debri cuts the rope.
etc.

it's a pipe-dream user.

Why does everybody keep saying space debris? Don't you realize that space debris is infinitesimally unlikely? The walls of the ISS are paper thin, and people's lives depend on it.

I think the biggest issue will be wind. My simplest solution would be to attach jet engines at several points that would provide both lift and wind stabilization. But, that would require tremendous amounts of energy that would need to be supplied constantly. I just don't think we have the energy resources to build such a structure.

The space station is in orbit along with that debris, making collisions both less likely and less energetic. The cable however at those altitudes would not be in orbit and therefore any collision by space debris would happen at extremely high relative velocity, striking with many times the energy as the debris that hits the ISS.

The walls of the ISS by the way are not paper thin, over half a meter of complex wiffle shielding covers the entire pressure vessel and is designed to spread the impact energy out enough that it doesn't penetrate.

>Geostationary Orbit Altitude
More like the dome in the sky

Space debris is not "infinitesimally unlikely", and your example of the ISS is just plain wrong since the habitable sections are entirely covered in shielding against micrometeoroid impacts, and te entire station is frequently manuevered in order to avoid things.

en.wikipedia.org/wiki/International_Space_Station#Threat_of_orbital_debris

why not make the counter weight the "base of operations" where everything is upside down in relation to earth? then you can fly spacecraft off of the base kinda like a space carrier deck.

Because flat earth

I don't get your first two points at all.
What do you need the trees for? I get that you need the material to build it, but why would you use trees?
And what is with the rocket? The climber is part of the elevator not a seperate rocket flying alongside.

The idea is to have a means to get things from earth to space.
You are just proposing what to do once things are there

>implying normie voters would care about space, look what little it did for Newt

Don't forget the Van Allen radiation belts. Not so bad when you zip right through them in a rocket, not so good when it takes you a day or two.

>Then you have to fly a rocket in such a way that relative to the earth it moves direcly vertically (an impossiblity to do)
What rocket? You mean from the top of the memeavator? When you reach GEO, it's already going at orbital speed. You only need to go really fast for LEO. And any point above GEO should pull you upward because of tidal/centrifugal forces. (read Niven's "The Integral Trees" to get an idea of what would happen) If there was a station at the counterweight, it should even have earth-normal "gravity" if you build it with the floor on top.

There are many problems we are far from solving with a space elevator on EARTH. The longest carbon nanotubes we've managed to make are only a few centimeters long. We're also not sure how we'd anchor it. We could feasibly build one on the moon as a "practice space elevator" using materials that we already know how to mass produce, like Kevlar. If you want to distinguish yourself as a pioneer of space travel, I'd suggest pushing for reusable rockets or "space planes", which would be an airplane with both air breathing and rocket engines or only rocket engines, allowing it to fly above the earth's atmosphere and into space. Because it's a plane, it would be capable of taking off and landing on a runway, which cuts costs because it's easier to find a runway than a launchpad. Obviously, costs are also significantly reduced by the space plane's reusability.

Have you ever considered a double tethering system?

Even if a space elevator wasn't feasible on Earth, it could be useful on the moon, except for a few things. First, it would have to be on the equator, while what water there is would be in craters at the poles. Second, mascons (mass concentrations) make lunar orbits less stable than they would be otherwise, and might limit the potential sites for an elevator.

en.wikipedia.org/wiki/Mass_concentration_(astronomy)

Woo-hoo, let's add a second point of failure!

>it works on paper.

Except it doesn't and thats the whole fucking problem..

>How much payoff is there if you can only run one climber at a time?

Why would you assume that limitation? If your "elevator" tower has multiple faces, you can have at least that many climbers.

If you can build the thing at all, and frankly I don;t think you can without impossibly-to-acheive purity in the materials, then you might as well build it with a ton of capacity.

>A fleck of paint or grain of sand moving at low Earth orbit speeds would hit with a relative velocity of nearly 7 kilometers per second

Velocity would depend on where it hit, though.

>Not to mention designing the lasers so that a climber passing at 200+ km/h doesn't strike and destroy them.

This is true, that's why you can';t have warning signs and gates by train-tracks, to warn motorists that a train is coming -- it is impossible to put anything near a track where a vehicle might pass...

>habitable sections are entirely covered in shielding against micrometeoroid impacts,

So there is paret of your answer...

>and te entire station is frequently manuevered in order to avoid things.

And there's the rest -- waves are a thing that can be induced in cables -- Hell, your moving "climbers" are going to induce those anyway unless you have some sort of hellacious damper system. Shielding or active defense mechanism like space-sharks with frickin laser beams for small stuff, dodge laterally for larger stuff.

Still, an effort to clear Earth orbit of as much trash as possible would likely be a Good Idea.

>(read Niven's "The Integral Trees" to get an idea of what would happen)

Read Clarke's "Fountains of Paradise" for a directly-space-elevator discussion of principles, wrapped up in a fairly weak novel.

Yeah, but LEO is where the dangerous debris is. It's moving fastest, it's most likely to strike the cable, and there's more of it there than anywhere else.

Hey retard, there's no land next to the cable you can post sings or lasers on, and the cable itself is being climbed by the climber, implying it will be pulling the cable through itself.

The train analogy would work if the train had nothing around it except for the tracks, and the train wrapped around the tracks in order to hold on, and the tracks had to be atomically precise in order to prevent them from tearing apart. No room for lasers, unless you dedicate an entire separate cable to housing lasers only with no climbers, and you still have to solve the problem of distributing megawatts of power to all those lasers as well as making the lasers light enough that they don't cause the cable to fail.

Well, yes, if you restrict yourself to the most retarded design for a space elevator conceivable, there are many such issues...

Equalization of tangential momentums results in giant mass plummeting straight down

as the climber pulls itself to the counterweight, it pulls the counterweight out of orbit...

How far out and how big is your counterweight?

Counterweight beyond the 24-hour orbit is constantly trying to go flying up to a higher orbit, tensioning the whole set-up.

That doesn't matter. If you lift something up by some amount you're taking energy from the cable.
The way to fix it is simple though, just use a strong magnetic field to maintain your orbit, or a very efficient engine, or by simply dropping just as much material downward as you lift up.

How far out and how big your counterweight is absolutely matters.

>the build challenge is finding a light enough material with the strength needed.
In theory you could build the tether out of any material so long as it's sufficiently tapered, but to build one out of modern materials you'd end up with a tether that is far too large and heavy to launch, or far too skinny and weak at the bottom to lift anything of value without snapping.
>you have to place it on the equator.
You actually don't. Placing it off of the equator will cause the tether to bow away from vertical somewhat, and dramatically so at low altitudes, and payload capacity would suffer, but it could still work (assuming you could get everything else about it to work).
As long as tension in the tether is greater than the weight of the climber, and the bottom of the tether is secured to the Earth (or at least dangling in the atmosphere), that shouldn't be a problem. A small amount of rotational energy and angular momentum is transferred from the rotation of the Earth itself into the system during ascent. Pic related.


All in all Space Elevators are a neat idea, but I don't see them ever working out. By the time the materials to make it feasible exist, we'll probably have reusable conventional rockets that outperform it anyways in cost and every other respect.