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The Space Elevator - Public or Private?
AtomicGoat writes "The Space Review reports that a Space Elevator may not get built without help from the U.S. Government, but the notion that 'the DoD can also provide a sense of fiscal discipline when dealing with large, expensive programs' sounds like an Onion story. Right now a small private company (Liftport), not NASA or the Air Force, is in the lead on revolutionary space travel."
Not public or private. I like my variables protected.
Of course it needs government support; you can't just put up an X-mile high tower without worrying about security, shared land use, population relocation, etc. These are all things that government does. Without some government muscle, a private space elevator company would be sunk.
but they do have a store. I want my liftport lunchbox! (http://www.cafepress.com/liftport.13005720)
That's a little over twice around the planet, people. Anyone who considers disaster scenarios should think about that. If something goes wrong, there's a possibility that the elevator cable would wrap itself around Earth, hard. Countries under the cable's path probably wouldn't like that. Their governments would make a great deal of noise, just considering the possibility.
Given that the governments are involved to that extent anyway, it's natural to assume that they will also want to oversee construction and whatnot, just to make sure Things Are Done Right. Now, do you want a government with no stake in the elevator watchdogging the process, or one that does have a serious financial stake?
In the same way that soon after the first aeroplane flights had been made, hundreds were being made: Given the high number of competitors and what we have seen so far, I think it likely that someone's going to win the Ansari X prize. Space flight's going to become cheap, and it won't take long for someone private to get a space evelator line up.
Well, people may like to make jokes about $800 hammers,
but the DoD folks are utter geniuses of financial management when compared withother federal agencies such as the FAA
or NASA.
But deployment...that's another story.
Regardless of who is 'in the lead', the US government will likely be heavily involved if not directly controlling a space elevator. Cheap transportation into space is far too lucrative, not to mention useful, to ignore.
Someday perhaps, but DOD, cost effective? Please... Giving something this to the government would probably ruin any efficiency in it, and a private company financing this...could happen, but most likely not for some time.
Support more choices in goverment-Vote 3rd party.
I dare you to drop a penny off of the top.
Queue, the correction hordes...
The grass is only greener, if you don't take care of your own lawn.
No you can't, you can't stay in the Van Allen radiation belt for a long time, as it would be necessary in a space elevator. For more info have a look at Wikipedia - Van Allen radiation belt .
But the platform would be built on international waters, and the elevator will reach into space, which no government owns. I don't see why any government should have to get get involved, if the LiftPort Group can get this off the ground without any government help, all the more power to them!
Sig? No thanks, I'm trying to quit.
Private: the elevator attendant (a Valued Associate) is your Customer Interface to the Space Elevator. The individual is in his/her teens, wears plenty of Company Issued "Flair," and beams incessantly as you say at what altitude you want your spacecraft released.
Public: the elevator attendant (a Civil Servant) only grudgingly speaks to you. The individual, dressed in a simple brown uniform, is in upper middle age, and won't release your spacecraft from the elevator without a 29B/6 form that's been stamped.
*ding ding*
2,756,234th Floor, Troposphere; Hardware, Automotive, and Lawn & Garden
Please watch your step as you exit and Thank You very much for shopping at Wal-Mart.
Friends help you move...
REAL Friends help you move dead bodies... ^_^
A space elevator would not so much be "put up" as "lowered down". The energy and materials requirements for lowering a cable from orbit are drastically different from building a tower to the stars.
When you lower a cable, it is relatively easy to anchor it to a floating platform in the middle of the ocean. Therefore, there is no worry about equatorial real estate, local population, eminent domain, or other government-dominated nonsense.
"This quote is a product of the Frobozz Magic Quote Company."
Great to see space elevator research is starting to pick up. I think its safe to say now that its the only cheap way to space. Governments will have to be involved, as will many companies. Wherever the anchor is will be a huge decision that could completely turn around a 3rd world nation -- or political instability could make it impossible. There's not many "safe" equitorial sites with lots of room for support organization -- look at a map.
The safety issue could really kill it though. If it starts to wrap around the earth, watch out. There has to be a way to "cut the cord" at this and and hope it flies out into space. Of course, a release mechanism like that is a liability in and of itself. So that's a very tough, maybe the toughest, hurdle.
Moo.
While a project as risky and expensive as a space elevator would seem to be solely in the realm of government, private investors could play a role. Already one company, LiftPort, is trying to commercially develop a space elevator.
*TRYING*
For a commercial startup to get the mass amounts of funding needed for a venture like this seems VERY unlikely to me. With the current cynicism surrounding space exploration as well as the exorbitant costs associated here, I just don't see it happening. But maybe I'm just a pessimist.
... is like "military intelligence" or "jumbo shrimp".
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
The "elevator" falling down is less dangerous than a sheet of newspaper falling down. It's that thin. It's not going to hurt anyone. They said it will likely break up and shred into small pieces as it falls. If it breaks anywhere within the atmosphere (due to weather, terrorism, plane crash, etc) only a few miles fall down and they simply lower some more down and reattach it. The few miles you lose in the atmosphere is a pittance.
It will be in international waters, off of South America (I want to say Peru?). So the buyoff of any government for land, airspace, etc is not required.
There are a LOT of hurdles left. Not only can the nanotube fibers not be made in sufficient length and quantity, but they have not even looked at what happens to a model of a few-meter wide ribbon in the atmosphere. We also don't have a lift vehicle capable of getting the big spool and counterweight they need up just past geosync orbit.
Real programmers use "copy con program.exe"
Not necessarily. Build it on a privately-owned island or some such. No regulations, no permits required, etc. I'd imagine that something like this would best be built along the equator anyways, for technical reasons. I don't know for certain, but I'd imagine that the tilt of the earth could cause problems. Maybe a floating platform, or in an equatorial country that would provide uber-security in exchange for the obvious economic benefits.
(tig)
Ignorance and prejudice and fear
Walk hand in hand
A space elevator will be a cheap-to-operate lifter once it's in place, and it'll have the nice advantage of being able to take items FROM space as well.
One of the companies that has been referred to in discussions of the X-Prize is going to use an inflatable balloon system. Ultimately, they plan on having a LEO space station supported by helium-filled balloons. (Insert usual joke about helium balloons. Insert usual technical rebuttal showing how It's Not As Silly As It Sounds).
If this system has potential, why not use this as the initial lift phase of a space elevator? Unspool out the first piece of carbon nanotube cable and leave the initial lift balloon tethered to its end. Hoist another spool, and splice it onto the end; inflate another balloon and send it up farther. Keep adding lengths until you reach the LEO altitude of your inflatable space station, then send it up along the tether. You'll end up with a string, supported at multiple points by small balloon and on it's end by a really big balloon.
That space station would help to support the weight of the tether, and could either serve as a launching point for the cable which would go out to GEO, or as a device to catch a cable lowered down from GEO.
The inflatable space station people claim tremendous efficiencies in lift because of the passive nature of the lifting force of balloons (negative buoyancy) vs. rockets (thrust). Why not use this approach to leverage the space elevator cable?
By the way, I'm thinking that all of this, once complete, would merely serve as the scaffold to support the climbers, splicers, etc., with which the final Space Elevator cables would be built, connecting ground to GEO.
The man who does not read good books has no advantage over the man who cannot read them. - Mark Twain
This problem can be conquored with adequate shielding- and thus isn't really a problem.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
Those are _VERY_ dangerous words historically.
I don't see that Nasa has "helped" space development much-especially the last 25 years. I can easily believe the world would be _further_ into space development without the various destructive government policies the last few decades that have turned the United States from an industrial powerhouse into a major debtor nation.
What the DoD ought to be more worried about is making the US into a technologically effective nation again(the US has a trade deficit even in high tech goods now).
Now, whoever creates a space elevator is going to instantly become a major, global power--and the DoD has reason to be concerned about such issues--but there are a lot of other pressing issues the DoD is also ignoring(i.e. the US borders just aren't very secure).
Unless the US government seriously gets its act together, I doubt very much it will have much of a constructive role in space development-this isnt' the government of Franklin and Jefferson any more-and is more like what they warned us against.
According to the http://www.liftport.com/faq.php#science2b FAQ the cable will break if it gets struck by lightening or hit by a Category 5 hurricane. Basically their argument seems to be that this won't be a problem because they'll build it where there isn't any lightening or hurricanes. That sounds kind of risky to me considering the massive amount of money involved. I mean huricanes I can see but isn't there lightening everwhere?
"... drowning in information,
security
Private companies don't need governments to take care of their security for them. A space elevator will not be a very tempting target to attack externally. You can only hit the very, very, very bottom, and if you break it, you just lower a replacement for the bottom 0.01% that broke off. The main threat is crazy people somehow sneaking bombs aboard, and governments have proven that they can be just as gloriously incompetent at security screening as anybody else.
shared land use
And if the private company puts it in the middle of the ocean, or on an island that they own?
population relocation
And if there's no population to relocate, like in one of the scenarios above?
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Government When you call to find out why you got released at 50 miles altitude rather than geosync from the Halliburton(tm) Space Elevator, your call has a bunch of mysterious clicks in the background before being cut off entirely. After you die horribly in the crash, it's announced that you were a terrorist who crashed the elevator deliberatly. The president goes on to bomb Syria, even though you'd never even been there.
"Seven Deadly Sins? I thought it was a to-do list!"
Yes, but you still need to worry about somebody flying a plane into it, either intentionally or accidentally. This is something that aircraft carriers are good for. Last time I checked, not that many private companies owned their own aircraft carrier...
"Freedom means freedom for everybody" -- Dick Cheney
It looks like what I knew -- or thought I knew -- about space elevators is a bit dated. Which amounts to "wildly inaccurate" now. For those of you who might want to see some direct comparisons between the current technology and what was believed a few years ago, see LiftPort's Frequent Misconceptions page. It was enlightening, at least to me.
Right now a small private company (Liftport), not NASA or the Air Force, is in the lead on revolutionary space travel.
They aren't the only private company planning independent space travel. For example, Space Island Group is planning to build multiple space stations by the end of the decade. They have a lot of former NASA engineers working for them.
LOL. I think we are talking about something more than a zoning variance. Hanging a space station a couple hundred miles offshore is still bound to make a couple of countries nervous. You're going to need some international diplomacy, not just a call to the local alderman.
"Maybe a floating platform, or in an equatorial country that would provide uber-security in exchange for the obvious economic benefits."
Do you know any third-world banana republics that are reknowned for great security?
-
When you lower a cable, it is relatively easy to anchor it to a floating platform in the middle of the ocean. Therefore, there is no worry about equatorial real estate, local population, eminent domain, or other government-dominated nonsense.
What about natural phenomenon, such as a hurricane or two blasting the platform each year?Tell that to the victims of the previous attempt at a space elevator. That is what everybody is imagining.
Then I can be bombarded with cosmic rays and become the human Torch! Flame On!
Seems to me that every piece of modern technology we have was at one point considered scientific fantasy with countless people declaring that it would never work. Space flight, cell phones, computers, telephones, airplanes, electricity, radio, recorded sound. Every single one of them had problems that could 'never be solved'. And guess what? They were solved.
If you had been at Kitty Hawk, you would have been yelling that the glider would never fly. And as it passed over your head, you would start claiming that they would never get it down.
Technoli
Basically, if you can think of a problem, they've solved it. It will cost about 10 billion dollars to build, and the materials will be available quite soon. Some examples of problems you might think of:
Weather: The anchor on the top is so heavy and is moving so fast that it won't be even shaken. Plus its strong enough to withstand the fastest winds.
Ionization in the atmosphere: Easy, coat it with gold at higher altitudes.
What if a plane hits it? It would survive--its strong enough that it would cut the plane in half instead of having the plane go through it.
"A ballistic missile can hit a very tiny area, and that is essentially dropped from orbit at high speed, not lowered slowly."
The different between a ballistic missle and a space elevator is huge. It's OK for ballistic missles to reach their target travelling over the speed of sound. That will probably not be OK for the poor fellows (or robots) trying to tie down the Earth-bound part of the tether. Also, a ballistic missle is a relatively discrete package; it is only in one place at a time. A tether needs to exist in many places (i.e. space, upper atmosphere, lower atmosphere) and remain stable in all those environments: much harder to do.
Not sure I would be so quick to dismiss the DoD budgeting process or their fiscal responsibility. A few anectodal popular press examples of fiscal excess should not be taken as the rule. (It is actually debatable if the Gov't really did purchase $800 hammers etc, or "padded" the cost of these items to cover larger non-public expenses). So, the DoD method of Planning, Programming, and Budgeting is actually very robust and has a good deal of merit. The system is widely refered to as the PPBS. It has been around since the 1960's and was first introduced by then Secretary of Defense Robert McNamara. "The PPBS is a cyclic process containing three distinct but inter-related phases: planning, programming, and budgeting. The process provides for decisionmaking on future programs and permits prior decisions to be examined and analyzed from the viewpoint of the current environment (threat, political, economic, technological, and resources), and for the time period being addressed." There is both a 5-year and a 10-year horizon for this planning and budgeting. There is a connection between this process and the "big budget." And overruns, well that is another story. :)
For the really curious, here is the process. http://www.dtic.mil/whs/directives/corres/html/704 57.htm
The space elevator was not created by science fiction writers. It was first theorized by Soviet scientist Yuri Artsutanov. Later there we some NASA papers that expanding on the theory. You can read about it here.
If you are going to debate the con side of this issue please produce facts not emotions.
UNIX/Linux Consulting
Well, if from now on we aren't going to build anything that *could* be a terrorist target, we just as well start living in trees instead of building anything ever again. Shit, trees could be a target, too! Now what do we do...
/tired of the "what about terrorists" question appending onto EVERYTHING
I have to question the legitamacy of the company altogether. The write-ups are of an amateur nature. Verbage and use of the language is poor in many areas and I would question that any company looking to fund that large of a project would present it's foundation of material in this way to the public. Examples are in the FAQs answering questions such as if a ribbon breaks; "Honestly, it will make a little bit of a mess". and other things they say in describing the strenght of the ribbon; "3-5 times as strong as needed", what about correct english as in 3 to 5 times stronger than needed. Some of it seems written at a 5th or 6th grade english level. Certainly not collegiate level as you would expect. And the frank public statements regarding liability would shun and serious potential investor in the group. Of course you can always send in your paypal donation. I see they did take the time and effort to get the 'take your money' part of the website right. Careful here, you might have been scammed.
Good point -- you build it on the equator for starters: hurricanes don't cross the equator. Second, you pick the place with the most boring, unchanging, weather on Earth. Given platform technology can already hack conditions in the North Sea and Gulf of Mexico, you should be okay for the rest of time. Part of the reason for using a sea platform is so that you can move one end of the elevator cable around (although ribbon would be a better description) so as to dodge orbiting satellites, etc, so there's some flexibility built in.
"Just once, I'd like to meet an alien menace that wasn't immune to bullets." -- The Brigadier, Dr. Who
The proposed site isn't really just some spot in the middle of the ocean- it's some spot in the middle of the ocean, on the Equator. Not only does this make it possible to place a station on the cable at a geostationary orbit, but it confers the added bonus of being in a place where hurricanes are actually extremely rare- hurricanes, cyclones, and typhoons tend (but not always) to originate in belts called Intertropical Convergence Zones that flank the Equator, but do not stretch over it- in fact, the Equator lies in the band of low wind and calm seas aptly referred to as the doldrums.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
...what a space elevator is, how it would work, and so forth, but really doesn't, check out this link. This is the NASA-sponsored report that basically declared it open season on space elevators. It's fascinating, in-depth, and answers questions such as "how do we build it" and "what happens when in falls/gets holes in it". A must-read for space buffs.
Looking for a Rails developer in Chapel Hill?
Or, y'know, a small island. Assuming they can find a small island in the middle of the ocean.
If it's so goddamn far from everything else, it's not going to make for a very efficient means of getting stuff from "civilization" to space, now is it?
Wait a minute. You think shipping goods an extra few hundred kilometers via container ship is somehow economically prohibitive? It's obscenely inexpensive and easy to ship goods by sea. It's the getting it to space part that's tricky.
They're entirely serious when they say, "Oh, we won't have to worry about the part that doesn't fly off into orbit, because we'll put it in the middle of the ocean." Right. That doesn't create its own problems, no, not at all.
Of course it creates its own problems. Namely, that we'd need to restrict air and sea traffic in a certain area, we'd need to find a suitable island for the project, and we'd need to create a special shipping lane for spacebound cargo. You seem to view these problems as showstoppers; I don't really see anything prohibitively challenging about the examples you cite.
When will you people get it through your heads that space elevators won't work?
Probably never. Then again, odds are I'm too dense to see the nuanced wisdom in your above statements, and my responses are all hideously naive.
Obliteracy: Words with explosions
For the initial elevator ribbon deployment, you're talking about 2 spools massing about 20 tons each, but once you've got the initial ribbon up, you use the cheap, cheap, elevator itself to build up the ribbon, so you're not paying typical launch costs for the whole thing.
To get the initial spools and associated hardware up to GEO, Brad Edwards calculates (if an MPD engine is used for the LEO to GEO transfer) that the launch cost could come downn to about $1 billion for 4 Atlas 5 launches -- about twice the cost of a single shuttle mission.
"Just once, I'd like to meet an alien menace that wasn't immune to bullets." -- The Brigadier, Dr. Who
1) it's not that long, and 2) if it breaks, only the part below the break falss; the part above flies off into space
If a job's not worth doing, it's not worth doing right.
1) This is a great idea; Nasa should scrap the shuttles and build one.
2) The government shouldn't have a space program. (Maybe the government shouldn't have too many programs at all.) This will be an outrageously expensive boondoggle, and we should just let private industry handle it.
3) Dude, when is private industry going to get around to doing that?
4) When it's good and ready.
5) Dude, private industry wouldn't even build the interstate highway system - a fulcrum of America's economy. What makes you think it will build a space elevator?
6) Communist.
Want to Know How to Cheat the GPL? Read On!
Kim Stanely Robinson has a lot to answer for -- every time the space elevator comes up, people drag up the plot from the Mars books....
To (once again!) answer the objections raised by this scenerio: Unlike Mars, Earth has a nice thick atmosphere. The elevator ribbon has a very low mass per unit length (indeed, this is one of the characteristics that make the elevator physically possible, not just sci-fi). If the cable is severed, only the stuff below the breakpoint would fall to Earth, and execpt for the bottom few hundred miles, would burn up in the atmosphere. The remainder should fall into the sea, and again, because it's so light, any that did somehow hit land would cause any major problems.
"Just once, I'd like to meet an alien menace that wasn't immune to bullets." -- The Brigadier, Dr. Who
Panama and Egypt now are simple means to get someplace a little cheaper than alternative routes. Before there were alternative routes, places like Gibralter and Suez were _much_ more strategic. From the time the first space elevator is built, until there is a competitor, whoever controls that space elevator is going to have de facto gate keeper authority over a block of resources that dwarfs those available on the planetary surface. Think about what nations like Spain, France, Portugal, the Netherlands and the UK did during the "age of discovery". The tiny little Netherlands was for a time a world power-based on its maritime strength. When that race started, it wasn't exactly obvious that the UK would become the hegenomonic power. I can easily believe in this case that someplace like Canada or Taiwan winds up playing a role similar to that the UK played--coming up from behind to seriously surprise the world.
Since a few of you are quoting a Wired article, let me remind you all of another article regarding the DOD's stated mission of "Dominating" the space arena and to deny other nations the ability to launch any platforms to space which we would deem to be contrary to our interests. See Wired magazine; "Peace is war" April 2002.
As you might recall from the article, Rumsfeld and others within the DOD have simply stated that space is too important to allow other nations to participate fully without our approval. Period. As an example, consider US lobbying and conditions in regards to the European GPS system.
from the article
Operation of a space elevator will not be allowed where it conflicts with our interests, this includes business interests too. Any venture providing access to space would most certainly have to have their payloads approved by the US government, even if the launching platform is 5000 miles out into the pacific somewhere.
Seems pretty clear, even if a private interest were to attempt to create a space elevator, they might find an un-invited "partner," regardless of their wishes. Soooo, might as well go with the flow and accept the DOD money right off the bat. No other way the project's gonna get done.
Someday these things will be wireless.
Speak truth to power.
But... You could build a space elevator with a non-geosynchronous orbit. Say for an extreme example, you anchor it to the north pole, and swing it around once every 24 hours. The cable will appear to point in the same direction, parallel to the ground directly at the pole all the time. The forces on the cable will be different, and it will fling whatever is launched from it along a completely different orbital path, but who is to say that is a bad idea? There are many reasons why you want non-geosynchronous orbits that go from the northern hemisphere to the southern. This would allow for that without requiring additional thrusters as it would take launching from a geosynchronous space elevator.
Don't get caught thinking one particular way, and assume you _need_ a geosynchronous orbit.
-Jesse
Nothing says "unprofessional job" like wrinkles in your duct tape.
Ok, I flipped through the site and couldn't find answer, so I'm going to ask it here and absorb the flames. What holds the orbital end up? Before you say "Nothing... it's in microgravity.", I know. But anything thing that tugs on the ribbon is going to pull the endpoint towards earth. It seems to me that that should have been the first question answered on the FAQ.
Let's see
The government likes to send things into space
The government isn't likely to develop a new technology to send things into space cost-effectively
There is a company that wants to develop a new technology to send things into space
How about the government just promise to use those guys if they prove to be cost effective? I mean a lot of the problem with public funding has to do with people funding things that do not work, or go over budget, in effect, allowing subsidies to make companies take on some of the worse fiscal aspects of public funding.
Why not just reward people who do the right thing, once it's proven they can do it?
And yes, right of ways, air corridors and related ideas are all things the government can help with. But, let's agree to do it as indirectly as possible, lest
1) the project be tainted by political ideas
2) the project become less efficient
These people want to turn a profit, let's lend em the money to do it, and promise them clients, that's what new businesses need. Let's not promise to bail them if they fail, and perhaps, they'll only try once they're sure.
If you can actually hit the elevator (which will be perhaps a few feet wide, not as easy to hit as a skyscraper) then all you will manage to do is snap off the very lowest portion of it, which is the easiest to fix.
First, I don't think you can just sew it back together. AFAIK there's no "fix" for a broken ribbon.
Second, if the ribbon is completely broken, the top will go flying into space. Its not just going to keep hanging there above the platform.
IOW if it breaks, you're back to square one (plus the experience).
We still have a disagreement regarding scale. Our plumb bob in the tether case is not to be built with string, nor will it have a "hand" which is allowed to move much, nor do we have an overweight "bob" at the end of the tether.
I would suggest a different example to suggest the relative difficulty: hitting a certain tile on the bottom of a swimming pool with a length of sewing thread.
Read their site. Theyr rely on centripital force to keep the cable taught, otherwise there would be no tension on the cable. They plan on putting the satellite outside of goesynchronus orbit.
http://www.liftport.com/research1.php
No, many people have proposed that putting it on the ocean would be better. Especially because a space elevator must be on the Equator, and the Equator is mostly ocean.
You have to remember that space elevators are mostly supported from the top, not the bottom. Don't imagine a tower which goes up to the heavens, imagine a rope hanging from a sattelite.
"Never attribute to malice that which can be adequately explained by stupidity." -- Hanlon's Razor
The difference is akin to dropping a rock and hitting a dime and accomplishing the same task with a plumb bob. The difficulty level is lowered further if you are allowed to move the dime in the process.
Now realize that we're talking about a thousand-mile plumb bob, subject to varying winds at all levels of the atmosphere, and it becomes somewhat more complex than the plumb-bob-and-dime analogy.
First, I don't think you can just sew it back together. AFAIK there's no "fix" for a broken ribbon.
I've heard the opposite from quite a number of fairly knowledgeable people when discussing this subject. I've never heard your position before your post, although that doesn't necessarily make it wrong. I admit I don't know enough myself to say for sure; maybe at this point nobody does.
Second, if the ribbon is completely broken, the top will go flying into space. Its not just going to keep hanging there above the platform.
Actually, it is. Even if you posit a fairly high-altitude attack with an airliner or a missile, you will cut off, at most, maybe ten miles of ribbon. That works out to less than 1/2000 of the length. Since the ribbon has an exponential taper, it will end up removing much, much less than 1/2000 of the weight, and the center of gravity of the whole thing will barely move at all.
Remember, a space elevator is neither a tower nor a suspension bridge. It is anchored simply to keep it from moving around under winds, small disturbances, etc. but the elevator itself is in orbit. If the anchor is removed, the elevator will stay. Removing a few miles at the end of the elevator is extremely close to simply removing the anchor, and so the rest of the cable will basically stay where it is. It may begin to move slowly, but it's nothing that couldn't be corrected with some small thrusters.
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A geosynchronous orbit is any orbit with an orbital period that matches the sidereal day, which is 23 hours 56 minutes and 4 seconds in length, and represents the time taken for the Earth to rotate once about its polar axis relative to a distant fixed point.
A geostationary orbit is a special case of a geosynchronous orbit where a satellite appears stationary from the point of view of an observer on the Earth's surface. The conditions for geostationary orbits are:
- The orbit is geosynchronous
- The orbit is a circle
- The orbit lies in the plane of the Earth's equator
The terms are incorrectly used interchangeably...A couple of other handy facts:
Have you thought for yourself today?
I thought *Arthur* owned this idea. Hey, he invented it. I don't care who makes a space elevator , if it
can be made then
a: it will cost.
b: It will make the historical thing about the panama
canal look seriously easy. Go become a good historian (hint: don't invest).
c: It won't happen real soon.
But, we can do some of this technology slowly.
Perhaps not on the same scale , but Arthur himself
understands that atomic bond limits make it unlikely that we can do it as far as we'd like to see.
He likes to dream. That's why we love him. Heck. He did get it right a few blinks of a chickens
nose ago, and couldn't patent it.
Never underestimate how much we love Sir Arthur.
If there was any justice in the world he wouldn't
be an ill man in a wheelchair. He'd be a passenger
on spaceshipone. He deserves it. Please Mr. Rutan,
you know he wouldn't care if he got back to the
ground breathing...
I for one would *love* Arthur to be our first hacker in space. But I'd love to suggest that he
has to take the ashes of his New York nemesis
up with him. Even though Ike hated flying.
Hey, Arthur. Consider it your revenge.
Do slashdotters understand this old timers joke or
not?
And then watch it go sideways.
Real Daleks don't climb stairs - they level the building.
Just to follow up from this, sounds like you're right. From http://liftport.com/research3.php
"Terrorists are unlikely to be able to break the elevator anywhere higher than 15 km or so; it can then be simply flown back down to the anchor by moving some of the counterweight mass a bit further out and will be back in operation in a couple of days."
Though they're not so much sewing it back together as they are trimming the end and re-anchoring. Good to know its so easy to fix.
What if the continent of Australia goes on a drinking binge and decides to take the elevator into space. Would this tend to slow doen the Earth and cause longer days?
..........FULL STOP.
According to who is Liftport in the lead on space elevator technology? As far as I can tell, this company is just a few of geeks who played with lego mindstorms and set up a fancy webpage. Their site hasn't changed in a year, and their team consists of mostly administrators who write blogs about unpacking and filing things. Their Liftport group umbrella has almost as many companies as employees. What have these people done that makes anyone think that they have more of a chance of building a space elevator than my kid brother Joey?
LS
There is a fine line between being a cultivated citizen and being someone else's crop. - A. J. Patrick Liszkie
Because chemical rockets are a technological dead end for getting from Earth to orbit--they just aren't going to give much better performance in the future than they are today. How can we state this with any certainty? Two words: mass ratio. Fuel makes up most of the mass of any rocket at launch. Most of the rest goes on infrastructure -- engines, fuel tanks, guidance computers, etc, leaving a tiny percentage for passangers, payload etc. And there's no massive improvements left to be made in chemical rockets: we have the periodic table, we know we get the maximum theoretical bang by burning H and O, and it's just not enough to allow cheap access to space.
You could turn to nuclear power, but, generally speaking, nuclear propulsion inside the atmosphere is verboten.
So then you're left with either inventing totally new motive technology for rockets, or turning to something else, something that uses the gravity well to its advantage: something like the space elevator. Other contenders involve balloons and so on, but thess operate at the cusp of the atmosphere, or LEO at best -- a space elevator gets you all the way to geosynchronous orbit and way beyond.
"Just once, I'd like to meet an alien menace that wasn't immune to bullets." -- The Brigadier, Dr. Who
Just to correct that one trope: NASA has not lost the plans for the Saturn V -- although many paper copies were destroyed, a complete set of blueprints exists on microfilm in Marshall.
The real problem is that the plans for the assembly lines have probably all vanished: all the custom jigs and other tooling created and built up for the Apollo program. It's one thing to note on blueprint that, say, a Saturn F-1 engine outer housing needs to be sintered to the cooling pipe network in one go, but how on Earth do you actually do that?
"Just once, I'd like to meet an alien menace that wasn't immune to bullets." -- The Brigadier, Dr. Who
Now let go. Does the string wrap around your head?
-- MarkusQ
As early as 1895, a Russian scientist named Konstantin Tsiolkovsky suggested a fanciful "Celestial Castle" in geosynchronous Earth orbit attached to a tower on the ground, not unlike Paris's Eiffel tower. Another Russian, a Leningrad engineer by the name of Yuri Artsutanov, wrote some of the first modern ideas about space elevators in 1960. Published as a non-technical story in Pravda, his story never caught the attention of the West. Science magazine ran a short article in 1966 by John Isaacs, an American oceanographer, about a pair of whisker-thin wires extending to a geostationary satellite. The article ran basically unnoticed. The concept finally came to the attention of the space flight engineering community through a technical paper written in 1975 by Jerome Pearson of the Air Force Research Laboratory. This paper was the inspiration for Clarke's novel.
Why would anyone engrave "Elbereth"?
If it's so goddamn far from everything else, it's not going to make for a very efficient means of getting stuff from "civilization" to space, now is it?
One minor point because I am too tired to answer the rest. Out in the middle of the see is by far the best place to put something if you want 'stuff from civilization' to get there. There is absolutely no cheaper and quicker way to ship large quantities of stuff other then by ship. For industrial applications, some place with sea access is absolutely the best place to put a space elevator.
As far as civilians, I think they will be able to live with taking a couple hour boat ride to get into space.