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The fact that we are talking about a japanese company called Obayashi making a carbon nanotube elevator to space is very cyberpunk to me.

Reminds me of Ono Sendai making wetwire jacks to the internet.

Makes me think of Gunmm/battle angel alita

here how it looks: https://www.google.co.uk/search?biw=1280&bih=629&tbm=isch&sa...

I agree on the publicity stunt feeling. Space elevators are thought-provoking stuff of science fiction. It would be fantastic if we could build them.

Most I've read on the subject (this article included) are very thin on details, or point out the great scientific hurdles and breakthroughs that still need to be overcome / made.

This article made me think of the publicity stunt some years ago to build a mountain of 3,560 feet high in The Netherlands for $432 billion. The stunt was taken seriously and became world news:

https://www.businessinsider.com/400-billion-manmade-mountain...

If this is indeed a PR stunt I wonder if it would reflect positively or negatively on Obayashi? Would be like proposing an unrealistic, probably under-priced project. Of course they don't say when it can be realized..

There is a very good youtube channel by Isaac Arthur where they look at different options.

There is better stuff like the orbital ring which looks very expensive but actually feasible with current technology.

I watched that entire video on space elevators - very fascinating.

We're only 1 to 1.5 orders of magnitude away from having a material strong enough? Maybe I've been working with computers for too long, but that sounds excitingly achievable.

Yeah, just wait 6-7 years and Moore's law should take care of it.

Okay, that's a joke people. There's no moore's law for carbon nanotube extension (that I know of). There is an analog of electric battery price reduction over time, about 15-30% per year. Here's a graph of it - https://electrek.co/2017/01/30/electric-vehicle-battery-cost....

Of course whenever we see a little bit of a pattern, we use a little bit of our ability with this language called math, and declare a law. Calling it a short-term pattern that may or may not continue into the future wouldn't help us feel smarter than the other people in the room.

Yet it somehow helped you.

Material science is tough. Check out engine/turbine material science developments. It can take >decade to get new materials into planes.

Yeah but isn’t that because aviation is an extremely highly regulated industry?

Those regulations are there for a reason. Safety is important. You don't want your space elevator climbers to fall down. A ripped cable would also be a pretty expensive accident.

Imagine untangling it.

<spoiler> Stanley Kim Robinson has very colorful description of space elevator falling on Mars. Basically it should loop around the planet accelerating during the fall, likely supersonic in the end and flatten everything in its path.

As a rule, the aviation industry auto-regulates first, and government regulators come later. That's the patter on most of the changes.

So, not really. It's a highly regulated industry, but this is not the bottleneck.

A space elevator seems like a much better concept for the Moon. If we could make a permanent Moon base with a space elevator, then it would be possible to use materials from the Moon to assemble things in orbit. Such a base would make it possible to start exploring the rest of the Solar system in earnest.

Launching from the Moon is cheap - magnetic rail and solar power can do the job and cut the need for propellant significantly and there is water enough to make e lot of propellant for delta-v's you'll need. With all that slack, we can relax a bit with mass and use simpler techniques to build ships. A lot of 3D printing and automated manufacturing.

On the not-so-bright side, we'll have to develop new metallurgy and other industrial processes based on local chemistry.

Where would the counterweight have to be for one end to be in high Earth atmosphere, balancing atmospheric drag with lift and gravity? My math tells me the end would be traveling at a relatively tame 260 kph.

Putting an elevator (or more likely a sky hook) at a lunar Langrange point makes some sense, because the tether doesn't have to reach the entire distance if we allow for 0.2km/sec injection/drop-off speeds. That's important, because lunar elevator/hooks are much longer than earth based equivalents, even though their strength and taper ratios are much more achievable (e.g. polyethylene 4:1). You'd want to keep launched weight for the tether as low as possible.

A huge advantage is that a hook at the far lunar Lagrange 2 would be very close to escape velocity (e.g. asteroids or GEO).

http://hopsblog-hop.blogspot.com/2016/08/lunar-sky-hook.html

http://hopsblog-hop.blogspot.com/2015/05/eml2.html

Article says they are going to use a steel cable.

Where did you see that? I see this in the article: "Carbon nanotube is the most likely material to be used for the cables."

A steel cable would have far too low a strength to weight ratio to work in a space elevator.

The first paragraph in the article says “…aim to launch two small (10 sq cm) satellites connected by a 10m steel cable from the International Space Station.”

The part you quoted refers to the material that might be used for a 96,000 kilometer cable.