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[RedKing]

While a space elevator is still impossible for the moment,(Though we're getting there)

Funny you should mention that.

There's a Kickstarter to fund space elevator research. Still at the research phase, but this isn't just some crank. This guy is a former JPL/NASA researcher and his company was doing this kind of research up until 2008 when the bottom dropped out of the economy.

Funny you should mention that, I'm the one who posted that in the kickstarter discussion...

Meh...I don't read that thread.

The problem with a space elevator is that none of our materials are strong enough at the moment(Well technically the are, but a cable with a multimile diameter isn't exactly viable.) Carbon nanofibers might work, but at the moment we can't make them long enough. As soon as we got 4 mm, a carbon nanofibre alloy can be strong enough, adding another thing to the list of problems that can be solved by putting the word nano in front of it.

But hey, they'll need money to come up with alternate methods/materials/etc, so I'm still all for people donating.

[MetalSlimeHunt]

Note that we will eventually have carbon nanofibers with the strength to support a space elevator, we just don't have them yet. This is also assuming we don't find something stronger in the couple of decades that it is projected for carbon nanofibers to make the required triplication in strength.

[10ebbor10]

Note that we will eventually have carbon nanofibers with the strength to support a space elevator, we just don't have them yet. This is also assuming we don't find something stronger in the couple of decades that it is projected for carbon nanofibers to make the required triplication in strength.

OF course. The only thing they need to do to have them be strong enough is increase the max length of a single fragment from a few micrometers to 4 milimeters.

As for other methods to tie it up: They can use balloons up to 30 km, and above that they can try and use magnetic buoys.(Though those could be better used for stabilization.)

[Sheb]

I'm curious, how do we know the max strength of carbon nanofiber?

[MetalSlimeHunt]

Presumably by hanging weight from one until it snaps.

[Sheb]

No, I mean the theoretical max strength. How do you know strength is going to improve by a factor of at least 3 ?

[10ebbor10]

No, I mean the theoretical max strength. How do you know strength is going to improve by a factor of at least 3 ?

You can't know the increase in strength of the nanofibers itself(which btw, can't really be improved), but you can calculate the needed improvement in strength of the alloy that will be used. Currently we can only make very short nanofibers, meaning the alloys aren't that strong (Only 30%-40% stronger than normal counterparts, and that was for a certain type of plastic.). Increasing their length can seriously increase the strength.

[Mech#4]

Is this like how a single thread of a rope isn't that strong, but all the fibers woven together compliment the rope as a whole?

[10ebbor10]

Is this like how a single thread of a rope isn't that strong, but all the fibers woven together compliment the rope as a whole?

Kinda, more like the difference between normal and reinforced concrete, where the nanofibers are used as the reinforcement.

[palsch]

No, I mean the theoretical max strength. How do you know strength is going to improve by a factor of at least 3 ?

You can actually create models of nanotubes and test those. The chemical structure is really simple, so you can actually model them more easily than most other materials. You can at least do basic simulations on basic molecular dynamics software, and I've seen more substantial specialised simulations in the past. At the same time single nanotubes can be created and tested on a small scale, with some tests showing near perfect strength compared to those models.

The nanotubes themselves have the highest possible tensile strength of any material yet discovered. Any structure made up of them is going to have points of weaknesses weaker than the tubes on their own. The ideal structure for an elevator cable would simply be continuous nanotubes all the way up, with no joins or breaks as you go up the vertical axis. Any other structure is a compromise and the only question is how much compromise you are allowed.

[darkrider2]

And now for something completely different.

[Sheb]

I don't see what normal vibration modes have to do with the strength. But yeah, the answer is "Quantum Mechanic", and I'm not advanced enough yet to do that kind of calculations.

[Scoops Novel]

FUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU YOU OBNOXIOUS LITTLE..... FFUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU. At least they made him donate money. For the love of that poor traumatized potential life, why? Fucking why?

Ahem.


Am i glad it's not the first music we sent out.

[kaijyuu]

And now for something completely different.

I find this quite hilarious.

[Guardian G.I.]

And now for something completely different.

NASA's choice of music indicates they are absolutely convinced that there's no life on Mars.