Japan to build Space Elevator

[madanthonywayne]

http://www.timesonline.co.uk/tol/news/uk/science/article4799369.ece
Japan is starting a massive project to build the world's first space elevaator

Now the finest scientific minds of Japan are devoting themselves to cracking the greatest sci-fi vision of all: the space elevator. Man has so far conquered space by painfully and inefficiently blasting himself out of the atmosphere but the 21st century should bring a more leisurely ride to the final frontier.

For chemists, physicists, material scientists, astronauts and dreamers across the globe, the space elevator represents the most tantalising of concepts: cables stronger and lighter than any fibre yet woven, tethered to the ground and disappearing beyond the atmosphere to a satellite docking station in geosynchronous orbit above Earth.

Up and down the 22,000 mile-long (36,000km) cables — or flat ribbons — will run the elevator carriages, themselves requiring huge breakthroughs in engineering to which the biggest Japanese companies and universities have turned their collective attention.

Japan is increasingly confident that its sprawling academic and industrial base can solve those issues, and has even put the astonishingly low price tag of a trillion yen (£5 billion) on building the elevator. Japan is renowned as a global leader in the precision engineering and high-quality material production without which the idea could never be possible.

The biggest obstacle lies in the cables. To extend the elevator to a stationary satellite from the Earth's surface would require twice that length of cable to reach a counterweight, ensuring that the cable maintains its tension.

The cable must be exceptionally light, staggeringly strong and able to withstand all projectiles thrown at it inside and outside the atmosphere. The answer, according to the groups working on designs, will lie in carbon nanotubes - microscopic particles that can be formed into fibres and whose mass production is now a focus of Japan's big textile companies.

According to Yoshio Aoki, a professor of precision machinery engineering at Nihon University and a director of the Japan Space Elevator Association, the cable would need to be about four times stronger than what is currently the strongest carbon nanotube fibre, or about 180 times stronger than steel. Pioneering work on carbon nanotubes in Cambridge has produced a strength improvement of about 100 times over the last five years.

Read the whole article at the link above

 

[Syzygys]

I think space elevators will never be feasable. Instead of puring money into that, Japan were much better of trying to solve its energy needs.

If there is a serious Gulfwar with interrupted supplies, there is going to be a cold winter in Japan...

Specially liked this one:

"the cable would need to be about four times stronger than what is currently the strongest carbon nanotube fibre,"

 

[Sciencelovah]

The title of the article inside the original link is a bit misleading, it said to build
the elevator to the stars. For a moment, I was like... there is no way you
can anchor an elevator until the stars, because the earth keep rotating and
revolving.

Anyway, the article is said it is to be built until 36,000 km distance, which
means until the geostationary point. Unfortunately there is no explanation
about the size of the elevator or its speed.

I am just wondering.. 36,000 km is about 3 times of earth diameter. Means, to
go and back would equal to 72,000 km or 6 times rounding the globe.

The existing fastest elevator is made by Japan and has speed of 750 m/m
(meters per minute), or about 45 km/hour. So, just for the travel time only
it will takes 1600 hr, or about 2 months. The elevator will probably have to
travel slower because it has to transport also some foods and drink for about
2 months? What about the stuff for recycling the water, poop, etc It sounds
a bit too science fiction for me. Nevertheless, if it can be made, it should be
the greatest science achievement of the century.

 

[spidergoat]

I know people who are involved in carbon nanotube manufacturing and scale-up issues, and they just laugh at the notion of a space elevator. Just being able to mass produce carbon nanotube materials would be a great benefit to the Japanese economy, that could be the only real goal here.

 

[Nasor]

I think space elevators will never be feasable. Instead of puring money into that, Japan were much better of trying to solve its energy needs.

Why, specifically? Is there some specific reason?

Specially liked this one:

"the cable would need to be about four times stronger than what is currently the strongest carbon nanotube fibre,"

This might sound like a serious problem, but when you consider that the last 5 years of research have seen a 100x increase in tensile strength, it seems very likely that the materials will soon be strong enough.

 

[kenworth]

is this from the ladder to heaven episode in south park?

 

[Syzygys]

Why, specifically? Is there some specific reason?

What is the economic upside of having a spaceelevator? As someone pointed out, it would be VERY slow. What if a hurricane hits the platform???

It is an interesting concept to toy with, nothing else...

Also, how do you keep it in place/90 degrees vertical with strong winds 2-3 miles up??? The baloons going around the world are going by 80-120 MPH in their altitude...

 

[NGM]

What if a hurricane hits the platform?

What if an airplane full of pissed off Muslims hits it? Hmmmmmmm? Upon it's completion, it would be their supreme target. Imagine 72,000 km of this cable falling back to earth. How much would gain speeds fast enough to disintegrate and how much would continue to the planet? What would it hit upon landing?

It's not like tall structures haven't been targeted already. This one would be a magnet for wackos.

I know! You could build one on each side of it with armed guards every 100 meters. Yeah, uh-huh, that would work.

What a fantasy.

 

[madanthonywayne]

What is the economic upside of having a spaceelevator? As someone pointed out, it would be VERY slow. .

Cutting the cost of putting something into orbit over 100 fold would not be a benefit? Here's another, more feasible option being developed in the US. A variation on the magnetic linear accelerator. Instead of using a linear accelerator, it uses a ring so that the speed can be built up gradually. It could only be used to launch pretty hardy payloads as the launch vehicle would be subjected to 2000g!

An enormous ring of superconducting magnets similar to a particle accelerator could fling satellites into space, or perhaps weapons around the world, suggest the findings of a new study funded by the US air force.

Proponents of the idea say it would be much cheaper than conventional rocket launches. But critics warn that the technology would be difficult to develop and that the intense g forces experienced during launch might damage the very satellites being lofted into space.

Previous studies have investigated the use of magnets to accelerate satellites to the high speeds required for launch. But most have focused on straight tracks, which have to gather speed in one quick burst. Supplying the huge spike of energy needed for this method has proven difficult.

The advantage of a circular track is that the satellite can be gradually accelerated over a period of several hours. And the setup is technologically feasible and cost effective, suggests a recent, preliminary study of the idea funded by the air force's Office of Scientific Research.

The air force has now given the go-ahead for more in-depth research of the idea. The two-year study will begin within a few weeks and be led by James Fiske of LaunchPoint Technologies in Goleta, California, US.

The launch ring would be very similar to the particle accelerators used for physics experiments, with superconducting magnets placed around a 2-kilometre-wide ring.
Mach 23

The satellite, encased in an aerodynamic, cone-shaped shell that would protect it from the intense heat of launch, would be attached to a sled designed to respond to the forces from the superconducting magnets.

When the sled had been accelerated to its top speed of 10 kilometres per second, laser and pyrotechnic devices would be used to separate the cone from the sled. Then, the cone would skid into a side tunnel, losing some speed due to friction with the tunnel's walls.

The tunnel would direct the cone to a ramp angled at 30° to the horizon, where the cone would launch towards space at about 8 kilometres per second, or more than 23 times the speed of sound. A rocket at the back end of the cone would be used to adjust its trajectory and place it in a proper orbit.

Anything launched in this way would have to be able to survive enormous accelerations – more than 2000 times the acceleration due to gravity (2000g). This would seem to be an obstacle for launching things like communications satellites, but Fiske points out that the US military uses electronics in laser-guided artillery, which survive being fired out of guns at up to 20,000g.
Long-range weapons

The US air force's interest stems from the ring's potential to launch small, 10-kilogram satellites into orbit, though the team says it has not been told what kind of satellites these are. Aeronautics researcher Alan Epstein at MIT in Cambridge, US, who is not on the team, says the ring could potentially be used as a weapon.

Aside from microsatellites, the launch ring would be ideal for delivering supplies to support human spaceflight, such as food and water, which are not sensitive to such high accelerations, Fiske says. "Nearly all of this materiel could be shipped via launch rings, resulting in major reductions in the cost of manned space activities," he told New Scientist.

http://space.newscientist.com/article/dn10180-huge-launch-ring-to-fling-satellites-into-orbit.html

This may be a good way to go. One system to launch supplies, and another to launch more fragile cargo like humans.

 

[orcot]

No timetable, no mentioning of any budget.

and they just laugh at the notion of a space elevator

Annyway if it's true that it would only need to be 4 times stronger then the current best nanotubes then that basicly means that we could already build a martian space elevator with only 38% of the gravity and the fact that the martian GEO is over then 2 times smaller (35000km VS 17 000 km).

PS 2000G's, Seriously?:bugeye:

 

[madanthonywayne]

No timetable, no mentioning of any budget.

Not entirely true:

Japan is increasingly confident that its sprawling academic and industrial base can solve those issues, and has even put the astonishingly low price tag of a trillion yen (£5 billion) on building the elevator.

PS 2000G's, Seriously?:bugeye:

Yep. But the military already has electronics that can survive 20,000g!

Anything launched in this way would have to be able to survive enormous accelerations – more than 2000 times the acceleration due to gravity (2000g). This would seem to be an obstacle for launching things like communications satellites, but Fiske points out that the US military uses electronics in laser-guided artillery, which survive being fired out of guns at up to 20,000g.

 

[Syzygys]

Cutting the cost of putting something into orbit over 100 fold would not be a benefit?

Shooting up stuff is cheaper and cheaper. Also, after everyone has their own personal satellite, what else we are going to shoot up???

Again, I don't think it is physically feasable, even if economically it is...

Not to mention, how are you going to build it? I keep seeing similar threads coming up on this forum, but we might as well discuss perpetuum mobile...

 

[Sciencelovah]

Cutting the cost of putting something into orbit over 100 fold would not be a benefit? Here's another, more feasible option being developed in the US. A variation on the magnetic linear accelerator. Instead of using a linear accelerator, it uses a ring so that the speed can be built up gradually. It could only be used to launch pretty hardy payloads as the launch vehicle would be subjected to 2000g!
http://space.newscientist.com/article/dn10180-huge-launch-ring-to-fling-satellites-into-orbit.html

This may be a good way to go. One system to launch supplies, and another to launch more fragile cargo like humans.

If I understand it correctly, the article says that by using magnetic accelerator,
the elevator can travel with the speed of 10 km/s which is equal to 36,000 km/hr.
In this case, to travel the overall distance of 72,000 km (two way trip), it will only
needs 2 hours.......

So far I just know that the fastest train which travel with magnetic force
(the maglev train) is 'only' operating with a speed of 581 km/hr.

 

[NGM]

the elevator can travel with the speed of 10 km/s which is equal to 36,000 km/hr.

And when a bug hits the windshield, OMG!

 

[madanthonywayne]

If I understand it correctly, the article says that by using magnetic accelerator,
the elevator can travel with the speed of 10 km/s which is equal to 36,000 km/hr.
In this case, to travel the overall distance of 72,000 km (two way trip), it will only
needs 2 hours.......

So far I just know that the fastest train which travel with magnetic force
(the maglev train) is 'only' operating with a speed of 581 km/hr.

Sorry, but you're confusing two different systems for putting things into orbit. The looped linear accelerator and the space elevator.

The linear accelerator would launch things into space by accelerating the launch vehicle in a loop using electromagnets. Once the target speed is reached, the capsule is launched into space without the need for rockets except for course corrections.

The space elevator is basically an elevator anchored via a satellite in geosynchronous orbit. The article didn't go into any details regarding how fast the elevator would be or how it would be powered.

 

[Syzygys]

The article didn't go into any details regarding how fast the elevator would be or how it would be powered.

yeah, those silly little detailes that we don't care about...

seriously, it is a freaking DREAM!! We will have human on Mars way before any space elevator shit...

Now if the Japanese are really considering this, than I am losing my respect for them. I know they also plan huge pyramid cities (another stupid and hugely idealistic idea) but I think that is more just a concept and they don't really think of making it...

 

[ElectricFetus]

As space elevator is possible with existing fabric... from the moon to L1!

 

[Syzygys]

Looked it up on Wikipedia. There are just so many problems, here is another one:

Powering climbers:

"Nuclear energy and solar power have been proposed, but generating enough energy to reach the top of the elevator in any reasonable time without weighing too much is not feasible."

And another one:

Satellites

"If nothing were done, essentially all satellites with perigees below the top of the elevator would eventually collide with the elevator cable. "

and yet, another one:

Meteoroids and micrometeorites

"Meteoroids present a more difficult problem, since they would not be predictable and much less time would be available to detect and track them as they approach Earth. It is likely that a space elevator would still suffer impacts of some kind, no matter how carefully it is guarded.
Far worse than meteoroids are micrometeorites; tiny high-speed particles found in high concentrations at certain altitudes. Avoiding micrometeorites is essentially impossible, and they will ensure that strands of the elevator are continuously being cut. "

The best is not to address these issues:

" The challenge of preventing fiber breakage from initiating a catastrophic failure cascade seems to be unaddressed in the current (January, 2005) literature on terrestrial space elevators."

 

[madanthonywayne]

Looked it up on Wikipedia. There are just so many problems, here is another one:

I agree, it would be an enormous undertaking. I think the looped linear accelerator has promise, though.

 

[OilIsMastery]

Do carbon nanotubes come from decayed dinosaur fossils like all carbon in the universe? No wonder the cables are so strong. T-Rex had giant muscles.