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Subscribe to RSSThis is the LiftPort Group's basic model for its proposed Lunar Space Elevator Infrastructure, also known as LSEI or "Elsie." LiftPort says the system can be constructed within eight years using commercial technology.
The space elevator concept has had its ups and downs — but this year, it looks as if the concept's proponents are definitely trying to push the “up” button again.
There’s a new Kickstarter project, aimed at setting the stage for a lunar space elevator. Space-elevator backers are trying to restart a competition for ultra-strong tethers. And a Japanese company has pledged to get the thing built … by 2050.
But veterans of the movement say one big thing is required: a revolution in materials science, and specifically carbon nanotubes. Or maybe boron nitride nanotubes.
"The materials are still the long pole in the tent, and I don't see the government getting interested in it," Bryan Laubscher, the founder and president of Odysseus Technologies, told me today. "That's disappointing to me."
Laubscher and other space-elevator advocates will take stock of the past year's ups and downs at the annual International Space Elevator Conference, running from Saturday through Monday at Seattle's Museum of Flight.
Railway to the sky
The idea of building a "railway to the sky" has tantalized dreamers for decades: Just send a satellite up to geostationary orbit, 22,000 miles up (36,000 kilometers up). Send one line back down to Earth, and another line up to an altitude of about 100,000 miles (160,000 kilometers) with a counterweight at the end. Secure Earth's end of the line so it's rock-solid, then start sending robotic climbers up and down the line, carrying cargo and passengers.
If the idea can be executed, advocates say it could reduce the cost of access to orbit from its current level of $10,000 or so a pound to $100 a pound — revolutionizing space travel and potentially opening the solar system to human settlement. That's the vision brought to life in science-fiction novels ranging from Arthur C. Clarke's "The Fountains of Paradise," published in 1979, to this year's opus by Kim Stanley Robinson, "2312."
Clarke once joked that the space elevator would be built "about 50 years after everybody quits laughing." Several years ago, LiftPort Group founder Michael Laine set up a countdown clock that predicted the "first lift" would come even sooner, in 2018. Today, six years seems way too soon, but at least people have stopped laughing.
The key sticking point has to do with the tethers, or cables, or ribbons that would be required to connect a terrestrial liftport with the elevator's orbital destination. Whatever they're made of, that connecting material would have to be stronger than any material that's manufactured today. A synthetic polymer called Zylon ranks among the strongest available, and space-elevator advocates measure its strength per unit of density at 3.9 megayuris. (The "yuri" is an unofficial measurement unit that was named after Russian space-elevator pioneer Yuri Artsutanov.) The specific strength of steel is about 0.5 megayuris. But the stuff of space elevators would have to be on the order of 30 to 100 megayuris strong.
For years, NASA offered $2 million in prizes to encourage the development of 5-megayuri material, but that challenge expired after last year's contest. The International Space Elevator Consortium is trying to revive the prize program at a lower level, but that won't happen in time for this year's conference.
"I'm confident there's going to be a well-attended strong-tether challenge next year," Ted Semon, the consortium's president and director, told me. "It's our numero-uno mission."
Who's going to build it?
Laubscher thinks it's going to take a government-backed development effort on the scale of the telecommunications revolution of the 1960s to create the materials required for building space elevators. "I actually think that the first space elevator will be built by the U.S. Department of Defense," he said. "The first one to build the space elevator owns space."
Carbon nanotubes are a good candidate, but lots of technical obstacles will have to be overcome in order to produce long, wide ribbons of carbon nanotubes that are strong enough and resilient enough to do the job. David Horn, the chairman of this weekend's conference, says boron nitride nanotubes offer 75 percent of the theoretical strength of carbon nanotubes and may be easier to manufacture.
"We haven't seen that it can't be done," Horn said of the space elevator concept. "But we really need to get this competition going to give people a financial incentive to do it."
Whether they're made of carbon or boron nitride or polymer, stronger materials will produce a payoff long before the elevator gets built — in the form of lighter, more fuel-efficient automobiles, airplanes, boats and, yes, even spacecraft. Cheaper, safer, easier access to space would make a big difference in the financial calculations underpinning the space elevator dream. "The world that we'll have with carbon nanotubes will demand that we build a space elevator," Laubscher said.
Here are some of the developments along the road to the space elevator:
- Liftport Group founder Michael Laine has just begun a Kickstarter campaign to raise $8,000 as the first step in what could be a multimillion-dollar effort to build a lunar space elevator, which is theoretically possible using existing technology. Liftport ran into financial and legal difficulties in 2007, and today Laine admits that "things went south for us" back then. This campaign, he says, marks Liftport's return to the fray after five dark years. "About six months ago, we had a fundamental breakthrough ... and we want you to be a part of it," Laine says in his Kickstarter video. It's debatable whether the lunar elevator concept will get off the ground, but Laine is optimistic. His current countdown clock calls for "first lift" ... presumably from the moon ... by Jan. 1, 2020.
- In February, the Tokyo-based construction company Obayashi Corp. unveiled plans to transport goods and passengers in a space elevator as early as 2050, according to a report from Japan's Yomiuri Shimbun. The trip to an orbital station would take seven and a half days. "At this moment, we cannot estimate the cost for the project," an Obayashi official was quoted as saying. "However, we'll try to make steady progress so that it won't end up as simply a dream." Although there haven't been any progress reports lately, Laubscher said "the Japanese are way ahead of America" in their enthusiasm for the space-elevator vision.
- Other places to watch for space elevator developments: One of the leading U.S. forums for carbon nanotube researchers is the Nanotechnology Materials and Devices Workshop, sponsored this year by the University of Cincinnati, the University of Dayton and the Air Force Research Laboratory. This year's workshop is set for Nov. 5-6 at the University of Dayton. Also, The New York Times reported last November that space elevators are on the agenda for the secretive Google X lab. "Google is collecting the world's data, so now it could be collecting the solar system's data," Rodney Brooks, an MIT professor emeritus and founder of Heartland Robotics, told the Times.
How realistic are these visions? Feel free to share your views in the comment space below. And if you're in the Seattle area, you might want to head on over to the Museum of Flight on Saturday. Even if you can't attend the three-day technical program for the International Space Elevator Conference, you can check out what's happening at the Family Science Fest.
Past chapters of the space elevator saga:
- 2008: Will the space elevator rise?
- 2009: Space elevator faces reality
- 2010: 50 years of space elevator dreams
- 2011: Space elevator: Going down? (Seattle Weekly)
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the dwarf planet and the search for new worlds.
Leave a Comment:
How about we get alternative energy going here on Earth.
THEN spend money on a space elevator?
Why not do both at the same time?
One thing that can you can look at is the tether as a giant generator, as it slices through the earths magnetic field it generates power. Not only would it likely power the space elevator but provide a steady pollution free source of domestic power as well. There is room to think big even today.
Giant rail gun to launch materials into space.
Building a giant stationary target for the worlds fruits to target?
I think we have a better shot at transporters using quantum entanglement.
General public is Atleast 10 years behind. What do I know?
Wind farms in the Atlantic will provide HUGE amounts of energy very soon.
My idea for the line dropped into our atmosphere was to have a type of balloon take you up to 50-100K feet to avoid all of the weight of the wire, allowing the space station end to be closer to earth. Requiring a much shorter rope. We will need a destination however, so its time to get a base started on the moon. Chopchop. Lemme know if you need any help.
CynicL1,
Yep, I was wondering what would happen with all that electrical build-up.
"How about we get alternative energy going here on Earth."
-"Why not do both at the same time ! "
* NEWSFLASH *
44% of the citizens of the USA cannot , will not & cannot conceive of themselves possessing the abilities to do 2 things at the same time & be successful at both...let alone the nation that THEY CLAIM is the GREATEST ONE ON EARTH ! They also believe that a "god" created the universe in 6 days but lacks the abilities to control men on the only planet god created with MEN on it .
It's all part of the new morals.... live in fear, be disingenuous, play victim & feign injury for sympathy & impede progress, science & the health of the nation whenever possible .
46% of us watch in amusement or horror & the remaining
10% either don't have a clue or are smart enough to keep their mouths shut .
Not all ideas that are theoretically possible are really good to implement.
The space elevator is one of them.
What happens on the ground when one of these massively long tethers breaks and comes crashing to earth from outer space?
What happens when some airliner runs into one of these tethers. Oh, the horror.
And talk about a spaghetti ball.
This falls into the category, Let's not and say we did.
.
"How about we get alternative energy going here on Earth".....I am not a proponent of the space elevator....but may I suggest YOU get an alternative energy going here on earth....for one thing, a long, long, long wire is going to have one HELL of a charge on it........your not thinking, your blaming...Kid's do that. If YOU got an idea for some alternative energy idea, ya know, were all ears!!!
Although this is not new idea, I find it exciting that at least people are talking about old and new ideas for space exploration again. Debate, planning and human creativity will get us there, hopefully sooner than later.
"How about we get alternative energy going here on Earth."
News flash it was done by Tesla over a century ago. how about you take history lessons!
I think too a space elevator would be a great approach to liftoff at least until we have teliportation and factories in orbit
Huston we have problem! the weight will knock the flying part out of orbit.
This will never work. Just the slightest tug, even from the line itself would pull the anchor satellite out of geostationary orbit, causing it to plunge to earth.
Tesla was a great scientist who was driven insane by Edison's harassment. Tesla made many absurd and baseless claims after he started to crack. Much credit is owed to Tesla for some of the basic ideas that run the world today, but forget his zero-point nonsense and most of the rest of his later works as well, he was literally a "mad scientist" at that point.
The space elevator, commonly known in sci-fi as a "beanstalk" (as in Jack & the beanstalk), is at least 3 or 4 fundamental advancements from feasibility. There is no guarantee that these new discoveries will EVER emerge. Even if we assume they must sooner or later find a magic string to hold the Earth up (I know, it's just a joke), there is no way of knowing if that time is months ahead of us or centuries ahead. Any "estimates" made currently could, very charitably, be described as educated guesses at best, and sheer fancy for the most part.
Tesla IS pretty much the reason society was able to make leaps and bounds in technology back the the 1900's and today. (He came up with Alternating Current, Edison came up with DC that has a range of only like 2 miles).
The man was a genius and people are STILL trying to figure out how some of his inventions worked. The man could create earthquakes. :p
That's the thing. He had a lot of awesome inventions that worked, but also some really crazy and unfounded ones that didn't. The ones we are "still trying to figure out" are the ones that never worked and never could because they came from his increasingly obsessive and delusional mental state over the years, mostly as a result of Edison's jealously and persecution of him, basically for being smarter than Edison. Tesla never made an earthquake. There is some evidence he may have come close to making the building his lab was in collapse with a harmonic wave machine (which is a very simple device that has been completely understood ever since Tesla built his). The fact is, despite the Tesla mythology, today we know vastly more about the subjects Tesla worked on than he ever did. This should not take away from his credit. He was first with some big ideas, and his work inspired a lot of later work that inevitably went beyond his own. We know more about spacetime today than Einstein ever did, but that doesn't mean he loses his credit for proposing the theory first.
Those questions have already been addressed. The base of the elevators would be located along the equator in the ocean. They also stated that due to the actual strength required for these tethers to work, it would be impossible to pull a 9/11 on them in an attempt to sever them. They would simply slice the plane into pieces and keep on standing.
Too many problems to overcome with the space elevator.
Why not try a StarTram type idea? We've already got most of the technology needed for that and it shouldn't cost more than $150B, less if we go for a cargo-only system. The government could even recoup some of it's investment by charging commercial clients.
Think of the possibilities that would open up if we could put hundreds of thousands of tons of cargo in space for <$100/kg. Large scale space based solar power generation, space manufacturing, asteroid mining, moon colonization and mining...
As fantastic as it would be to have a space elevator, the largest problem with having one is always overlooked.
Noise pollution.
Having a cable that long vibrating like a gigantic harp string in the atmosphere would create an amazingly loud racket - even with vibration dampening - that could be heard thousands of miles away.
This is a better way to get payload into space than using chemical rockets, but the timing is bad. In the 1960s we had money for the space program, after all the debt we do not now. This is one reason you see the private efforts, if they can find customers that want to put up payload then they might have a business.
First, almost all concept ideas for the space elevator have it built as a wide ribbon, not a round cable. The reason being the need for surface area that the crawler can grip and use to move up and down. Thus making it much harder to vibrate.
Secondly, contrary to popular belief, air is a very poor medium for sound waves to travel through. Sound propagates by transferring mechanical energy from one molecule to another, through a medium, in this case air. The closer the molecules are together, the less energy lost exciting the next one in the chain. So even if this ribbon was able to vibrate to the point it gave off noise, there would have to be an extreme warm layer of air on the surface, and a cold layer above that, that would trap the sound waves in a sound channel, in order for it to go any distance at all. At most you're talking about a few miles.
Third. Using the harp string example, the sound is generated from the midpoint of the string. The midpoint for this ribbon in the elevator would be around approx 11,000 miles up. In space. Where there is no air to propagate sound. In space, no one can hear you scream.
(I was a Sonar Technician in the Navy for 13 years, so I do know a bit about what I am talking about.)
"The first one to build the space elevator owns space."
But only until the second one is built by someone else - probably by the Chinese after they steal the design.
"Thus making it much harder to vibrate."
Hardly... indeed it would make it far easier to vibrate since it has a greater surface area to volume than a round cable would have. Remember that the air currents at different elevations are going at different speeds and in different directions - it would most certainly generate a lot of noise.
As to assuming that only the middle of the cable would cause noise, that's simply wrong in the case of a space elevator - in this case only the part in the atmosphere would cause noise - but it would cause a gigantic amount of it.
You're trying to compare apples to oranges and that's just not how it works. A vibrating object completely inside of a transmission medium tends to generate the majority of the noise from the center, but far from all of it. The amount generated by the portion of the cable in the atmosphere would still be on the order of megawatts of total energy.
The ribbon for a space elevator would be amazingly loud.
The Space Elevator has been talked about for many years,
think about it a short trip to low earth orbit. To me, it would be one of the greatest achievements of all time and a grate achievement for all Humanity.
Very nice article Alan.
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Here are my comments on the video.
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During this time in 1980 Carl Sagan narrated a new series
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The video is best played at 1080p Full screen.
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@chouse
While you bring up some good points, no where in any of the searches I just did, did I find anyone who believed that vibration noise from the tether would be an issue. I see information on just above every other possible issue than can raised with this. Which tells me that it's pretty much a non-issue, as this has been discussed for 60+ years.
This is probably because it would be fairly simple to induce a counter wave to whatever freq the tether is oscillating at. Either from the base, or more likely from devices along the tether itself.
You also have to take in account the material that will be used to create the tether. The requirement is that the material must be able to support approx 5,000km of it's own length before breaking. In comparison, Titanium or steel and aluminum alloys can only support 20-30km. Thus the material to be used must be at least 200 times stronger than those 3 examples and most likely will have far different sound producing qualities.
Last thing. Most of the talk concerning what to build this out of usually revolves some form of nanotube. Interestingly enough carbon nanotubes are excellent vibration dampeners all by themselves.
http://www.sciencedaily.com/releases/2005/01/050121091524.htm
It cant work! The slightest tug would pull it down,,,the satellite would then have to orbit faster than the spin of the earth,,,,it just wont work!
"no where in any of the searches I just did, did I find anyone who believed that vibration noise from the tether would be an issue"
Which doesn't change the reality one bit.
Every substance we could possibly make the cable out of would be prone to vibrations - some less than others but that doesn't change the fact that we're talking about ~50 miles worth of length in the atmosphere subjected to direct wind forces (the magnitude varying from section to section based on air density and wind currents), as well as the ENTIRE length of it subject to vibrations from the crawlers riding up and down it.
The main reason that you won't find it discussed much in materials intended for non-scientists is that they don't know what the magnitude really will be - and that's EXACTLY why I mentioned it exactly as I did. It is indeed a subject of discussion among the people trying to build them, and Clarke mentioned it at least several times himself. The fact that it doesn't show up in articles for "citizens" doesn't remove that key fact.
It WILL vibrate very loudly unless we can somehow learn how to make a force field based tether of some manner or another - but any physical cable/ribbon WILL vibrate, even something made of nanotubes.
If it vibrates, it WILL produce noise. I'm not sure how there's so many people being so skeptical about a well known property of all physical substances - especially ropes and strands being subjected to semirandom forces from semirandom directions.
@Kornfed, it certainly will be possible if we can made a strand strong enough - but of course there are side effects that some of the readers here don't want to believe. (head in sand or lack of scientific knowledge perhaps)
At the orbital end of the tether, they need to construct a satellite whose centripetal force on the cable can be adjusted dynamically - very likely by paying out more line as a heavy load is coming up to counteract the downward force of the load - and the reverse would be needed when a load was being brought down. The key part is keeping the tether appropriately taut to at least try and minimize the vibrations on the cable - but there won't be a way to eliminate it completely; despite what some of the non scientist "experts" here want to assert.
I have an uncle that published a feasibility study on a space elevator, he states that 3 inch long, flawless carbon nanotubes would be sufficient. we don't have flawless nanotubes that meet the requirement yet, but it is doable.
of course if the lunatic, anti-science idiots have their way (both right and left), we will soon go back to the dark ages
It doesnt matter if the line is strong enough, the pull of its weight would be enough to pull an anchor satellite down. Once it starts heading back out of geostationary orbit, the satellite would have to travel faster than the spin of the earth to remain in orbit. It is not feasible!
Satelites have a very sensitive balance for geostationary orbit, so any weight attached and pulling back toward earth would cause an orbital decay and fall of any satelite and even if this can be compensated for you still have wind load on the teather and space debris to deal with. This whole idea is pure fantasy which is why the government will not back it.
The only way i could see it working would be a counter weight tethered out from the anchor satellite. That counter weight would have to keep a geostationary orbit from further out, thus exerting force to counter the weight of the line, and the payload.
@chouse
Can you provide links or locations in which you obtained your facts? No matter how techinical the information may be, I'm pretty sure I can understand it. As I said I spent 13 years in a job that required me to understand the ins and outs of sound propagation in detail. Link to the website, name of the book, title of the scientific paper and the journal it was published in, etc etc.
Lol, my own quote from the article already suggested it and I didnt even realize it hehe. I still dont see it working. the anchor satellite would have to carry all the line on it, and somehow guide the line down while guiding the counter line out...I suppose with small guideing rockets. Then you have to deal with atmospheric winds that would be hard to counter adjust with the counter wieght. There would be constant adjustments that would have to be done.
"It doesnt matter if the line is strong enough, the pull of its weight would be enough to pull an anchor satellite down"
You're assuming the space station is AT the Clarke orbit - but indeed to balance the force out, the space station will have to be PAST that orbit - which of course adds additional tension to the cable. This has all been studied and as long as we can get a strong enough cable it won't be an issue.
"Can you provide links or locations in which you obtained your facts?"
Seminars I've attended where PhDs were discussing this very subject are hard to give a URL for, ya know?
I suggest taking a peek at scholarly journals and you will run across it to - don't have any links off the top of my head.
"As I said I spent 13 years in a job that required me to understand the ins and outs of sound propagation in detail."
Not to knock your MOS and on the job training, but I'll take a bunch of actual scientists' opinions any day of the week.
This is the most stupid idea that I have ever heard. What a colossal waste of money. I use this assinine project as an example of science gone beyond the ridiculous.
People take about the bridge to no where, but this idiocy beats it by a long shot.
Ok, that makes sense to me now. Of course there would be problems with prevailing winds that would tug it one way or another, pulling it down it would seem. I suppose you could adjust with directional rockets on the satellite. Maybe they should try it!
"Of course there would be problems with prevailing winds that would tug it one way or another, pulling it down it would seem"
Yeah there would be several types of forces perturbing the cable, which as I was saying above would cause it to vibrate - including forces from wind, solar wind, adjustments to the orbit of the anchor space station at the spaceward end, and from the vehicles riding up and down it.
Indeed it would be nearly impossible to stop it from vibrating along the length, which of course would cause it to make a lot of noise in the atmosphere.
Of course, you also need some way to tension the base anchor (taking in or letting out slack at the ground station) and the spaceward anchor - but either way, pulses of vibration would be regularly running up and down the length of the cable - and with a > 22,000 mile long cable that's a lot of rippling.
Of course even with a nearly ideal material, the length will expand and contract at least a small percent in response to temperature cycling and a few percent of > 22,000 miles is several miles of slack that will potentially need to be pulled in or let out as needed to keep appropriate tension on the cable.
Some people think you can just toss up a cable and it's magically going to stay there, when there really would be a lot of dynamic forces working on it - but with a strong enough material we should be able to do it nonetheless.
@chouse- um, my understanding is that the noise issue is partly a red herring. at the tensions described, any sound created would be so far above human hearing as to be a non-issue- but that doesn't in and of itself mean it won't create problems, just that the true issue would be vibration. clarke once described the ribbon as probably needing to be something like 18 feet wide, by less than 1/12th of an inch deep. we would never hear it on earth...
....but imagine this: 26 inches of guitar string, with a few pounds of pressure, can be heard in our atmosphere a dozen miles away. picture say 50 miles of this huge ribbon, at huge tensions....no, we'd never hear or probably even feel a thing, but at some point a million miles away, given doppler, that sound would eventually drop into the range of hearing. this sound would project how far.... (i tend to think it could be virtually inescapable, going on forever, but have no basis other than fantasy for that thought...) maybe it would be like a sonic beacon....or a sonic insect repellant.
i just get this vision of some insect beings, going crazy from the noise 200,000 light years away, gathering together...'can't we destroy the planet making that infernal racket? send a drone!'
thanks for the odd thoughts....
It would be actually emitting a variety of frequencies at different altitudes due to all of the various influences placed on it as the Earth spins and different parts of the cable are exposed to solar pressure/wind and atmospheric wind and the nature of the atmosphere in each of the zones - and the tension will be variable so the pitch would be shifting pretty constantly - indeed I'd expect it could sound quite a bit like the cue music from Star Trek: The Motion Picture when V'ger shows up - an odd polyharmonic bass guitar sort of noise.
We can do it, but we lack vision. Just look at Curiosity. They had vision and did something "crazy". We need a visionary leader again without the ultimate contempt of opposing parties. Where are the days where we disagree, but we are all still Americans. Right now we spend to much time fighting each other, rather then supporting the American ideas. We are our own worst enemy right now, not Iran, not China. Ourselves.
Vote for Sanity and people willing to work together.
I took about 188 years, from concept to finish, to build the undersea Chunnel, linking France with England. It's consider one of the Seven Wonders of the Modern World.
The space elevator was conceptualized by Yuri Artsutanov in 1960. As for the space elevator being built by 2050, I would add fifty more years to that estimate, say, by 2100. Reason why I say fifty years later, is the changing politics, changing economies and the will of the people applied to a firm consensus to build it. All these factors have to coalesce together.
So given the circumstantial progress of human history and its timelines, I've learned that for every expert prediction of WHEN they think some major undertaking will yield a global product or history-making system built by the hands and minds of men and their machines -- add about 50 years or so to their predictions of when it will ACTUALLY happen.
Scuse' to all, I humbly need to quickly add a correction: "It took about 188 years, from concept to finish, to build the undersea Chunnel, linking France with England. It's consider one of the Seven Wonders of the Modern World."
(If I was able to do that, call me the immortal engineer possessing resources far beyond mortal men. But I am just a mortal like every other man. And even this seeming delusion of grandeur will one day be achievable... say, all things being relative...in a thousand years, perhaps?)
rradiko, I'm holding up one hand, maybe you can read between the lines. Correct my spelling, or my spell check, if you insist. Or feel the need.
Ya know this is simply stupid on many levels.. 1 a tether 120 miles long will weigh a lot no matter what it is made of.. 2 any load put on it will pull the space anchor out of orbit.. 3 Maintaining a geosync orbit 24/7 will be an astronomical pain in the a$$.. 4 Wind load and drag on the tether will be insanely high at 4 inch CS times 3 =1 sq. foot times 1760 times about 68 miles = 119,680 sq. foot wind load and factoring atmospheric density shift from sea level to the Thermosphere on a sliding scale gives us an estimated total wind load of 40,000 square feet.. Now add a few mph breeze and the 1,000 mph rotational speed at the equator and you have an insane amount of drag.. It will never work and is just pissing money away.. And what will all this drag do to the rotation speed of the Earth over time??
By using a magnetic beam instead you eliminate some of these problems mainly drag.. Position it at the north or south pole you remove rotational hassles, the 1,000 mph thing.. You could also use the magnetic polarity repulsion effect as propulsion.. Set up a power station in space and beam microwave or laser energy down to power it.. I did not go to M.I.T. but I sure know when someones thinking is totally stupid.. Are we that dumb to go along with this???
All you need to do, if you can build the elevator, is build a huge solar array at the far end in space, and send the power down the line.
Ed a modest thought about the economics of energy consumption in space would remind is that the value of energy collected in space is highest when that energy is used in space. Launching space craft into Earth orbit, is one of the most energy intensive operations we have yet conceived.
Only because we push space craft straight up with brute force. It's the simplest method, but I don't see how it's the most efficient.
BrainCandy-3328906 - Assent vehicles (aka Rockets, Space Shuttles, etc.) follow a curved path, not a straight one.
Amused - I think BrainCandy was talking 'straight up' as opposed to launching horizontally from a runway. Of course they take curved paths, but 'straight up' as in vertical launches is what I think he meant. :)
So, in that regards, I agree with BrianCandy - it ''feels'' like the rockets that are launched horizontally after taking a ride to 50,000 ft on an aerodynamic parent vehicle are the most 'fuel efficient'. However, that's probably just not feasible for the larger orbital and inter-planetary rockets.
I was thinking more along the lines of merging aircraft technology with space vehicle tech. We have planes capable of supersonic flight in the upper atmosphere. We should be designing vehicles that can operate under their own power from takeoff to landing. Rockets don't rely on aerodynamics for lift, they lift the vehicle with sheer brute force alone. I just don't see that as the most efficient way to designing a space craft for anything more than single use.
Any civilization that stops innovating eventually finds itself dead or enslaved. The Asians know this, and to some extent the Europeans know this, so where is the American Govt now? In the 1960s we were at the forefront of modern innovation and it is this reason that we stand here today, at the brink of destiny. The people have to realize that if THIS Govt. won't do it, in 2012 we should vote in those who will (Not saying go Repub. or Democratic) but choose a side that will give serious thought to space development. Space Development will ALWAYS create jobs at an exponential rate if we give serious time to it.
Any civilization that stops innovating eventually finds itself dead or enslaved.
The middlemen who control the flow of goods make out pretty good too. And probably wield more economic might. Think for example, oil speculators.
Tether (String Really) see also Ancient Minoan Greek (Clue)
You don’t have this experience so I give it away free. Unwind two or three spools of thread, mercerized military type, (Coats, Corrente, mercer, 5000 metros, Art. No. B963m, 20, COR9902) each having a length of 5,000 meters, I will not tell you how as it makes the story is too long. If one of those spools has break, just one, the failure rate is 1/3.
The string is about one hundredth of an inch diameter, strong enough that you will cut your hands if you try to break it. The 15,000 meters had only one break and the three spools took about 90 minutes to rewind each. I am going to round off just make this narrative easier to follow. The sample above is comprised of about 60 million diameters with one defect; the failure rate is 1/60,000,000. Because I have other examples will complete this note using this sample.
If I had to span 200 a kilometers string I need a failure rate of much less than 1/60 Mega diameters. What would have to be? Something: like 1/800 Mega diameters. I will give just a few more examples to allow you to discover the principal I am using, 20,000 kilometers 1/80000 Mega diameters, 200,000 kilometers 1/800 Giga diameters.
This on round number means that to span such large distances I need material that has a defect rate of about 1 in a trillion, which if I guess right is very low defect rate.
That being said the geometry of this design need only one failure in a trillion.
But the manufacturing from original resource materials, on to supply spools, on to trucks, off trucks, into the satellite assembly area, off the spools on to the satellite spool, button up and ship to rocket assembly, payload attachment, launch, rattle, vacuum of space, hot, cold, dry all represent a subject area that needs to be addressed in any realistic deployment.
That subject area may be best addressed by not doing as many of those steps as possible, replacing these by using a manufacturing technique, process, or method directly space to produce the string and deploy it as many times as needed to survive a one in a trillion defect ratio.
If you do discover such a space manufacturing technique you can build space elevator, but in the mean time take course in probability and statistics.
…
Sorry to be so vague
Clue: Theseus had a "clew" which she had obtained from Daedalus. In some versions of the myth it was an ordinary clew, is just a simple ball of thread. See also other variations clew, cleowen, cliwen, clywe ball. More: “clue” - phonetic variant of clew (q.v.) "a ball of thread or yarn," with reference to the one Theseus used as a guide out of the Labyrinth. The purely figurative sense of "that which points the way" is from 1620s.
The simple design where the defect equal in size to the diameter of the tether is enough to break it is just as simple as it was intended. But the trick is to press on one clear idea at a time, kept independent of others to simplify, and reduce distractions.
One idea is gather all the material properties on one place, if hard to know which ones to follow upon, so I just rely on limited experience, but knowing that dozens of other properties exist and are likely a good source of new possibilities. Cohesion, non Newtonian behavior, elasticity, dozed of properties from elections.
First if we start a single string that breaks, we can imagine that two or more might be better. In fact the string I used above is twisted of three smaller threads that are made up many filaments; after all one defect in 80 million is not all that bad. The experienced fisherman appreciated braided string that allow connection loops without knots, essential for high stress applications, and less breaks and tangles, twisted string is a nightmare of tangles.
Design a new meta-material is a good start to expand the possibilities, and will no doubt prove independently useful, after all this just one place to start, there are others. One principle that is required is that which could be called a meta-design principle, and seems to apply to many technologies in the example above, is to first look at where a design or plan or technique might fail. I mean to “look first”, and get used to the idea that failure will happen, but the clue is that if you look for failure points first, what you are doing is (not developing a negative attitude), but by failing early and often and sooner rather than later, you save valuable, if not irreplaceable, time, time better spend on finding ways that don’t fail. Meta-design principles need to be included the design process first and applied every step along the way in everything else that you work on, to reduce rework and avoid costly catastrophes.
The idea of manufacturing string in space, changes the assumptions enough, to improve the design. Just a little bit like complaining about all the money being spent on space, but finally noticing that is really spent on Earth. Many ideas developed for space, have improved more useful on Earth.
If a space tether were built like the cables on suspension bridge, a starter cable is launched between piers, and provided a support and guide to wind additional cables. The space version has no piers, but developing a pair of satellites, that would hold a starter tether, and provide a whole new set of navigational programs to allow a pair of satellites to hold a very long tether between them.
If we were to have such a starter tether, we would have something on which to wind additional fibers and manufacture a tether with a reduced failure rate.
Next those satellites could make the next extension of a starter tether and the winding process could extend the next section, keeping the failure less a problem.
This is good place to stop, and develop the math to calculate the failure rate, in systemic manner for this simple, build, extend, wind technique. Also the better the base fiber, the longer the extensions considered, to cover the whole distance and the less handling, this keeps the costs down, and form the basis of figuring how much material might be needed, and to include meta-material properties to improve design and control.
Having long tether amplifies problems, and suggests solutions. If the material is too elastic, control become more difficult, a sport kite handling is improved with stiffer lines, allowing longer lines and higher displays.
A meta-material having less stretch, might also be asked to have a damping property, strings vibrate under tension, setting up harmonics. Some if these properties may also be used to control the winding process, and detect problems developing along the tether.
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As others have commented the tether sky crane phase, is worrisome, I haven't see much published on tethered experiments, but it does seem problematical.
http://cosmiclog.nbcnews.com/_news/2012/07/25/12952477-what-a-win-or-loss-on-mars-will-mean
... when the spacecraft is supposed to blaze through Mars' atmosphere, spring a parachute, pop off its heat shield and let loose a rocket-powered sky crane platform that will hover about 66 feet (20 meters) above the Martian surface and lower Curiosity on cables(tethers). Then the cables will cut loose and the sky crane will fly itself out of the way, leaving Curiosity to get down to business.
Having fiddle bit with stringy things, very large kites, and remembering the expensive "tethered" satellite failures of years ago, if I were to point to the most vulnerable part of the landing sequence it would be these "cables" from the sky crane phase.
I would like to see the details of this design, and testing done, because this looks like one area that is the weakest link.(prediction?)
Much more generally is that lacking a heavy lift rocket capable of launching a larger Mar vehicle having a robust decent stage (to significantly) slow the vehicle, to enter the atmosphere, and to land protected from a cloud of dust; this scheme is too clever by half.
It this design works then we will have a new word for miracle, "Marsacle", otherwise a new Murphy's Law, "strings expected to untangle, don't".
Well congratulations, the Curiosity Rover made it, now for 100 more!
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The Tether concept has been tried twice, by an Italian satellite team.
It might be tried again, but, the assembly would need to be fully tested, in big lab. But remember a mile log building would need to have 130,000 loops, wound and unwound, without flaw. The central achievement would be a mile stone in technology, the record for minimal failure rates. We might not apply this new technology to reach The Moon, but spinoff applications will raise standardsm on Earth.
You are correct - it will be very difficult to accomplish.
But, if we don't try, it will be impossible to accomplish. :)
Space Elevator? ... Sorry, I am still laughing.
Sorry, I am still laughing.
As that preceded every great invention, maybe they're on the right track.
"I've called science fiction, 'reality ahead of schedule.'" -- Syd Mead, Industrial Designer.
Caveman Grug
The wheel? … Sorry, I am still laughing.
;-)
I'm not laughing, I'm just confused. I'm trying to recall the arguments of Galileo when he proved that heavy and light objects fall at the same rate to overturn the weakest part of Aristotle's philosophy. If you dropped a heavy ball and a light ball connected together with a tether, would the light ball fall faster pulled along by the heavy ball or would the heavy ball fall slower held up by the lighter ball? The answer was neither because both fall at the same rate. Now move the experiment to low earth orbit and extend the tether several miles. You may need to add a bit of velocity to one of the balls to take up the slack in the line but when this all comes to equilibrium could you get this arrangement to orbit perpendicular to the surface of the earth? If so would the center of gravity be somewhere along the tether? Or would the two balls orbit each other with the tether acting similar to the gravitational connection of the earth and moon? Or would the whole arrangement settle out to a horizontal configuration? Help me guys, there appears to be something missing here.
"Is this elevator going UP or DOWN...?"
Lady, this one goes sideways....
Make the tether from duct tape.
I don't know how many Yuri's is t is but it always works.
Scientists need to go back to the basics:
if something doesn't move but should: WD 40
If something moves, but shouldn't, duct tape.
See how easy science really is?
You should have someone use duct tape to tape your hands together so you can never share such ideas again. I actually felt clusters of brain cells die after reading your comment.
Hahahaha! Your humor is noted.
A single ribbon of regular duct tape possess about 60 pounds of tensile strength. (This was uncovered in a "Duct Tape" episode in that TV show, Mythbusters). Sorry , but your repair job'll need a lot more materials strength than that, to serve as a space elevator's cable.
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A Gigapascal is unit of measure for strength of material. The strength of tethers (ribbons or rope) is usual the tensile strength. Tensile strength is how much force is needed to pull the tether until it breaks/fails. How strong a tether for a given amount or density of material is important. Grams per cubic centimeter (g/cc or g/cm**3) are used to measure the density. 1 gram per cubic centimeter is the density of water.
Yuri (in honor of Yuri Aatsutanov), and so a tether with a linear tensity of 0.001 kg/m that breaks at 1000 N will have a breaking strength of 1 Mega Yuri.
http://nextbigfuture.com/2009/01/understanding-strength-of-materials-and.html
I certainly don't want to deter any one from banging on this problem. I for one have had a complete problem with the space tether on one very key point. I can see it being anchored to the ground...perhaps an engineering feat all in it's own....but really, I mean in all honesty, really, what is going to steady the top end??...don't say antigravity, momentum, rockets or magnetic repulsion, cause then I get to laugh....just draw the force diagram, include the weight of hypothetical rope and the elevator car and work form there, gravity, static electricity, wind drag, particle forces, magnetic forces, the works....why, oh why can't you see the top end is going to "give", meaning like it's gonna move, so much so that at some point near the half way point you drag the whole thing back down to the ground.....
Ok, so if you really think you got that part of the basics physics solved (don't even try me...go to a college physics prof...but if he laughs, don't say I told ya so)...if you really pass that part of the test....I do understand the goal of the nanotubes etc...I even have dibs on the goat milk spider silk for my own space project, but a bit of engineering substitution may be in order here...part of the one cable idea (which won't pass the human safty test, they will want two) is too save weight. It might be time to take the hit on that part of the project, I sugest three or more supports...or even three supports of three cables each....and each support is made from above and lowerd down simultaneously, with a truss like construction to each cable. Kinda like look at the problem from reverse, not how to get up but how to get down, and break the problems into smaller chunks so as to make it easier to solve the larger problem....that is how engineers think. It is that type of thinking that will solve the problem, let the ADVANCED materials science from the sci fi realm replace the standard solution all in good time. Meanwhile you now have another way of attacking the problem....and remember, the static charge is going to be ENORMOUS, but if your smart, that problem can very well be the one part of the whole thing that makes it feasible...there is the energy that can be harvested to drive the car up and down. NOW, what in the name of hell, holds the top in one place????
Till I see that answer explained in terms of ergs and joules and foot pounds per meter, it must be magic. My profs would never of accepted a solution that just said, yea, man, the top of the tether just sits there in standard orbit....hahaha.....
The top end is a satellite in geosynchronous orbit around the earth, and there is an additional balancing arm extending up from that satellite to counterbalance the tether.
It's steadied by the very same force that keeps geosynchronous satellites from drifting out their orbits and wrecking our GPS and communications systems - ie its just an application of the laws of gravity.
If you're truly interested, all the numbers in ergs/joules/foot pounds or whatever is there in the scientific literature at the end of a solid google search.
(The numbers are, of course, beyond the limits of what current technology can achieve. Otherwise we'd have already built one and would be using it to launch all our satellites, space stations, and interplanetary probes. Space elevators can put things into orbit at 1% the cost of rockets.)
I wonder if they will use Black Widow webbing.
Actually, the real top has to be well above geosynchronous orbit. Geosynchronous orbit (about 22,000 miles up) is where the outward force caused by the desire of the object to fly off on a tangent (because it wants to go in a straight line but the gravity of the Earth isn't letting it - centripetal force) balances the pull of gravity.
The center of gravity of the mass of the ribbon has to be balanced by a mass above the geostationary point if you want the ribbon to point straight up - the average needs to be geostationary.
Try swinging a weight at the end of a string, and play with both the weight of the object and the length of the string, and you'll get a better feel for this. Then tie an additional weight in the middle of the string and see what happens.
Actually the top end is a mass in orbit providing the balancing force to the tension on the tether :
http://science.nasa.gov/science-news/science-at-nasa/2000/ast07sep_1/
Note the Geosynchronous point is the mid point of mass for the system not the end point.
But factor in atmospheric drag.. Take a 4x8 foot sheet of plywood outside on a breezy day and multiply that force by 5,000 to 10,000 times and then try to figure out what counter force would be required to offset that and keep your kite string tight.. Have you considered what this drag would do to the rotation of the Earth over time??? Stupid idea and a giant toilet for money to be flushed into..
@amphiox "Space elevators can put things into orbit at 1% the cost of rockets"
How is that possible seeing as how space elevators dont exist and never will. The physics just does not support this fantasy of Clarkes.
Wouldn't a space elevator 'pop' the atmosphere, sucking all Earth's oxygen out into space like a straw from a fountain drink?
No.
again, I don't want to deter anyone from finding the solution, there is ALWAYS a solution, but please, do the math, at least that way you can define the parameters.
People have been doing, and redoing, the math for 5 decades. It can work, provided you can (a) find a strong enough material for the tether, (b) get it assembled. Neither violates any laws of physics, we just don't have solutions for either of them yet. Welcome to the collision of science and engineering!
honesty, no stranger to the math on this one....precisely why I am so skeptical. Only a few seem to really grasp that the top is not "tethered"...yea, I am laughing, several seem to think that geo sync is some sort of magic anchor point...in fact gps sattelites need constant resetting...the atmosphere can grow and shrink by astronomical amounts in releative terms to this problem, making coefficints of friction hard to get right, most people don't even realize the terms mgh and totally missed the true scale of the enterprise, absoltely no one notice the fact that the potential e difference betweeen surface and "up there" is an enormous factor in it's own....and imagine if the earth slowed by a small percent in rotation, the "tether" would propel ahead very fast (being polite)..if the string was indestructible everthing destructible in it's path is a goner....if the bottom end was tethered beyond realism, the top tether WOULD be pulled down....it seems simple to model the problem with a balloon on a string, but many of you are even getting that model wrong....again.....the top is NOT tied down...IT WILL move.....of all the problems, that's the one that will be the toughest to solve....we could in fact just knot up regular manillar rope and pull that part of it off...sure it'd be some seventy feet in diameter, that is all an engineering problem of scale....holding the top part still is more difficult and has been such a subject of math abuse that at this point, where serious money keeps coming to the table, that the math abuse MUST be pointed out. I do not consider the problem unsolvable. But there has been plenty of white wash thrown at it....I recall only a half dozen years ago when a certain vice preseident seemed to helping some freinds apply for grants to study over unity amplifiers...not the same problem, but math abuse just the same.......A simple way to look at it is through the stoiciometery and the equivalence princible...you are trying to beat the energy expended by a surface to orbit rocket....we believe it can be done, BUT, can it? When you do your force diagrams, keep that in mind. We are in a gravity well, the energy will be the same one way or another.....only rube goldberg will deny that.
The very first thing that's needed to build a space elevator is extremely strong tether material (and you have to think about it not as a building rising up from the ground, but as a rope hanging down from a geostationary satellite, it's kept up by the centrifugal force of the earth's rotation and the satellite's orbit, not by support from the ground).
A building material, in fiber form, with a tensile strength hundreds of times that of steel.
Yep, what a waste of time and resources to try and develop something like that. So specialized, can only be used for space elevators and nothing else....
No, I think the very first thing is getting past the concept of up and down in a weightless orbit, and I think it means little to be above or below geosynchronous altitude. What would be interesting is the orbital mechanics of two masses tethered several miles apart and the stable configuration. Could such a configuration make artificial gravity? Take two capsules, tether together, apply a bit of momentum to one and they start orbiting a center of gravity producing a centripetal force. (pardon me if I got the wrong force, its been a long time) The old Verner von Brown doughnut shaped space station and the "2001" space station did the same thing. Maybe the astronauts on the ISS could provide a little demonstration, tie a couple of weights together, set them spinning and make a little YouTube video. Would be fun.
Here's a question; why are advertisement's running amok on all MSNBC articles?
Extending down into and over the text and obscuring information is quite annoying.
Why don't they fix that before we venture into the lofty realms of space elevators?
Hey ForePlinger I agree with you. I think someone at MSN is getting >>PAID OFF<< because the large amount of SPAM dating websites on MSN message boards is OUT OF CONTROL!!!! And I collapse them and report them but they come right back. I think someone at MSN is getting paid under the table to keep them at the top of every comment page. We need a way to get them banned for good. Someone needs to be fired at MSN!!!
What will the jet stream and vibration from air do to the tether?
Would vibration from air currents make sound?
Would the tether attract lightning?
Would ice form on the tether at high alltitudes and increase the weight or jam the elevator?
Instead of trying to teather to the ground, why not just make a sky hook (think of it as a fishing line dangling from space)? A skyhook wouldn't need to be as strong or long. The end can be up high enough so that normal civilian aircraft couldn't reach it (ala a 911 terrorist attack couldn't be done). Basically, you'll need to build scramjets to reach and dock with it, but not full rockets. The cost per pound of payload would be higher then a tethered system, but certainly a lot lower then the current costs. Thoughts?
Space elevator on the moon is actually very feasible with the technology we have right now. But the questions would be why? There isn't even perm human presence on the moon, and is there gonna be that much traffic at moon to justify it?
If something you need in Earth orbit or elsewhere in space can be found on the Moon, it's a lot cheaper to get it into orbit from there than most anywhere else. Even something as prosaic as the initial counterweight for an Earth space elevator, which can be rocks, has to get into Earth orbit from somewhere. So it could potentially pay for itself by making a Moon presence worth the effort. But it's a long shot to say that is the best thing to do with the resources it would take in 2050. That's more a leap of faith.
hopefully this will be done commercially
because it will fail
use the generator on a teather for example
to much friction between space and earth to be able to elevate safely
If we're going to dream big, I'd rather do something a bit more practical. Like building a railgun to toss nuclear waste into outer space, or towing an iceberg to an area of the world that needs fresh water.
I think the 8K is to make his rent for a few months.
This should have been published April 1.
Who's volunteering to hang on to this while they attach the counterweight?
How much weight do we have to hang at 100,000 feet to counter balance this?
Which equatorial country gets the connection?
Do we have to change the size of the counter weight to adjust for the load on the elevator?
If so, will we have a bucket on the end that we can pump water into to adjust the ballast?
Who has to haul the water up? Maybe we can bring the SR71's back and convert them to tankers and use them to dump water into the tank.
What happens if a storm comes by and wraps the counterweight around the main tether thingie. You have a knot in the rope at 80,000 feet and two tethers wrapped around each other. The elevator won't run. Who shimmies up to unwrap it?
What happens if the elevator gets stuck, who goes up the rope to fix it?
Will Jack do it?
Is there a giant up there? Or gold? Probably not, no geese fly that high.
Why not just tether the moon for the moon colony?
You could have various bus stops on the way for polar orbit satellites, sync orbits, etc. Maybe express service too.
I've always favored a solar powered tractor beam in sync orbit to beam up supplies and passengers.
I'm up too late.
What ever happened to space stations?
"Insanity: doing the same thing over and over again and expecting different results." ... Albert Einstein
Two cables might be better, the one with an elevator going down could transfer energy to the one elevator going up. Just a thought!
Why use a cable in the first place?
A very powerful laser and a very small payload. Nanotechnology is the way for space exploration, i.e. take the monkeys out of the equation.
look at the practical - this will never be built because of the expenditures needed would never be given because they are in the hands of politicians - they can't see beyond their own nose and many would love to see nasa go belly up anyway - even if somehow in our wildest imagination, dollars were allocated for this project, it would be cancelled by the fundamentalist christian voters since they would see this as building a ladder to god - can't have that - this will never be more than an interesting thought experiment
Here's a thought experiment - how many more giveaway programs could the government create if all scientific funding was ended??
Didn't they give up on this idea because the cost keep it repaired would be horrendous and extremely difficult to pull off?
Meanwhile the entire world drowns in debt. PLEASE...space elevator? Why not just throw billions/trillions into an all out effort to figure out how Scotty could "beam up-down" Kirk and company?