Report: Space Elevators Are Feasible 374
Daniel_Stuckey writes "It's the scourge of futurists everywhere: The space elevator can't seem to shake its image as something that's just ridiculous, laughed off as the stuff of sci-fi novels and overactive imaginations. But there are plenty of scientists who take the idea quite seriously, and they're trying to buck that perception. To that end, a diverse group of experts at the behest of the International Academy of Astronautics completed an impressively thorough study this month on whether building a space elevator is doable. Their resulting report, 'Space Elevators: An Assessment of the Technological Feasibility and the Way Forward,' found that, in a nutshell, such a contraption is both totally feasible and a really smart idea. And they laid out a 300-page roadmap detailing how to make it happen."
Arthur C. Clarke introduced me to space elevators (Score:5, Informative)
It's a very well-written novel that focuses on many of the technical aspects of building a space elevator.
Re:Arthur C. Clarke introduced me to space elevato (Score:3, Informative)
Or, just read the linked report by a team of ACTUAL scientists instead of a SCIENCE FICTION story written 35 years ago.
You can't, unless you want to pay for it.
Re:Arthur C. Clarke introduced me to space elevato (Score:5, Informative)
Or, just read the linked report by a team of ACTUAL scientists instead of a SCIENCE FICTION story written 35 years ago BY AN ACTUAL SCIENTIST.
FTFY.
Re:Arthur C. Clarke introduced me to space elevato (Score:5, Informative)
Have you read it? Let me know if it's any good. To me, it just looks like a scam to get people's money.
No money involved, they give it away for free if you know where to look:
http://www.virginiaedition.com/media/spaceelevators.pdf
Archived here:
http://www8.zippyshare.com/v/72888832/file.html
http://www.sendspace.com/file/16c8xj
http://wikisend.com/download/118300/spaceelevators.pdf
Re:"Feasible" doesn't necessarily mean "Advisable" (Score:4, Informative)
Yeah, if you want a materials strength nightmare, forget about the elevator cable.
Think about a foundation strong enough to withstand the pressures of a 100-200 mile high tower pressing down.
Why don't you think about familiarizing yourself with the concepts behind the space elevator? There won't be anything like that. The end of the cable "floats" in the receptacle. It hangs from its anchor asteroid.
Oh wait! Lemme get my unobtainium!
Why don't you instead get a quick education in the topic we're discussing before you flap your yap?
Re:Arthur C. Clarke introduced me to space elevato (Score:5, Informative)
Radiation shielding not feasible (Score:4, Informative)
Using it for transfer of organic matter (i.e. humans) above LEO is not feasible due to the speed/shielding needed
The worst part of Van Allen belt is about 19000km wide and starts at around 7000km high. Apollo moon missions passed trough it at roughly 15km/s, spending roughly 2*21 minutes in it.
The astronauts received roughly 1rem of radiation through 3 layers of thick aluminum radiation shielding.
That is 1/5 of the yearly the limit in US for people working with radiation.
At reasonable speed (~200m/s) the elevator would take ~26h to pass through the belt, meaning it would need at least 75x more radiation shielding than Apollo did and that the lift would need 15m thick aluminum honeycomb walls (using 70's technology).
Even with todays technology the shielding will be way too bulky/heavy for elevators to be viable alternative to rockets for above LEO human transfer.
Re:Flying pigs (Score:5, Informative)
Re:Radiation shielding not feasible (Score:4, Informative)
Simple solution for the Van Allen belts: remove them.
https://en.wikipedia.org/wiki/... [wikipedia.org]
High Voltage Orbiting Long Tether, or HiVOLT, is a concept proposed by Russian physicist V.V. Danilov and further refined by Robert P. Hoyt and Robert L. Forward for draining and removing the radiation fields of the Van Allen radiation belts[29] that surround the Earth.[30] A proposed configuration consists of a system of five 100 km long conducting tethers deployed from satellites, and charged to a large voltage. This would cause charged particles that encounter the tethers to have their pitch angle changed, thus over time dissolving the Van Allen belts. Hoyt and Forward's company, Tethers Unlimited, performed a preliminary analysis simulation, and produced a chart depicting a theoretical radiation flux reduction,[31] to less than 1% of current levels within two months[32] using the HiVOLT System.
If you're going to be building a space elevator, getting rid of the Van Allen belts is a relatively easy task in comparison.
Not even a 1/10 of the current Space-X price! (Score:2, Informative)
Their estimated price is $500/kg which is a ridiculous price.
Today a falcon 9 can launch 13150kg to LEO for $50million.
The projected elevator can lift 13150kg to LEO for $6.6million.
A nice improvement until you consider that a reusable falcon 9 launch will cost perhaps $500,000.
Which means Space-X with a little luck can reach $38/kg.
It is not hard to imagine that with modest success at re-usability Space-X can drop the cost from $50million to $5million with just a reusable first stage, which would make the Space-X price $380/kg.
That makes space elevators uneconomical before they are even built.
Now a careful reader will note I am arguing GEO vs LEO prices. Once in LEO a ion engines can be used to make the transition to a higher orbit with all of the same efficiencies of an elevator and they already exist.
I fail to see the economics of a technology with a huge up-front cost and that it looks like a much less expensive investment in rocket technology can devastate.