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Space Elevator Going Up
Adlopa writes "The
Guardian newspaper reports on scientists' efforts to realise the space elevator, as first described by Arthur C Clarke in his 1979 novel 'Fountains of Paradise'. Advances in materials science mean that 'a cable reaching up as far as 100,000km from the surface of the Earth' is no longer an impossibility and 70 scientists and engineers are discussing the idea at a conference in Santa Fe today."
Any excuse to hang out in Santa Fe is a good one.
It's all very well wanting to build things that appeared in Sci Fi novels, but they fail to take into account the reality of the modern world. If someone's willing to topple a couple of 107m tall towers, what do you think they'd do to a 100,000km high space elevator? Ignore it?
That said, it is a neat idea, and if we can realise it, then great. But is now the best time to be building this kind of stuff?
Imagine the fact that the tip would accelerate as it fell...most of it would end up burning up in the atmosphere. Also imagine how little of the earth's land area lies along the equator. Not much. It might cause some localized devastation, but it's not a world-breaker.
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I don't mean to sound too condescending, but really, the centrifugal force of earth's rotation makes that impossible. I would have been humoured if you would have stated imagine a 100,000 km cable being hurtled at the moon when I move there. For it to fall to earth would mean the earth would stop spinning...highly unlikely given what we know.
You might be able to argue that inertia from the atmosphere would allow it to operate like a whip, but even that is farfetched. I doubt they would implement such a system without properly addressing such an issue.
Be more afraid of Near Earth Objects. Of course those things fall from roughly 4.7E17 km. Why the hell don't people imagine that?
Fuck Iraq and let's cough up roughly 12 space elevators instead.
Hate me!
I swear to god, if my eyes roll any harder, they're going to fall out of my head.
It's not like we're talking about a high tension cable here. The cable's structure will be balanced by gravity -- the center of gravity will rest at the geosynchronous point, meaning that the bottom half will be falling toward Earth while the top half will be moving away at an equal rate. (Disclaimer: my degree is in English and I'm relying on this thing called "high school physics class"...)
Really, it depends on where the cable snapped and what the nature of the accident was...
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From the article: "When we actually start launching this it's going to be kind of boring," Dr Edwards said.
After watching rockets (and shuttles) explode into spectacular fireballs, boring is just fine with me. Considering the majority of mass on any rocket is used to just get it to a level of orbit, this could be a nice way for us to start working toward the moon (and eventually beyond) again.
The really exciting will no longer be GETTING into orbit, but rather what we can do once we get there.
Tequila: It's not just for breakfast anymore!
But there is another problem: if it burns, will the resulting particles be hazardous for us to inhale?
Carbon nanotubes are primarily, well, carbon. Burning up would create the same stuff that charcoal makes, CO2. Potentially less toxic than second hand cigarette smoke. There may be some other chemicals in there, but the whole idea is to make the tube out of a single material, the nanotubes, to make it strong. So, yes, research is good, but toxicity is probably not the biggest issue.
Tequila: It's not just for breakfast anymore!
Sigh.
Who modded THAT insightfull?
"Imagine an accident. I wouldn't want it to happen to me!" Is not insightfull.
We get these inane comments with every article about transport.
Electric cars: Imagine getting electrocuted.
Supersonic planes: Imagine a supersonic collision with a building.
Space elevator: Imagine it falling on you.
Ship: Imagine it sinks.
Train: Imagine it derails.
Etc, etc, etc.
We don't need to have those modded up! They're not saying anything original.
You can't take the sky from me...
a) Carbon nanotubes are strong but very, very light. They have a high surface area per unit mass. In the lower atmosphere, the cable would float to earth like a piece of fishing twine; in the higher atmosphere it would just burn up.
b) Not really. Airborne traffic is smart enough to deal with comms towers, skyscrapers and hurricanes. This thing does not move - all you need to do is fly around it.
c) Yes it does. In order to advance space traffic, we need to get to geosynchronous and LEO MUCH cheaper, allowing us to loft the larger masses necessary for more ambitious space missions. Getting big tonnages out of Earth's gravity well cheaper and more reliably than is currently possible would be a BIG win for space travel.
But how will they protect it from, well, planes at altitudes below 100,000 feet?
3 words: Restricted air space.
You can't take the sky from me...
So how exactly do you come up with a budget for a project that calls for an unknown (but massive) amount of nonexistanium, delivered to orbit no less?
The same way that NASA came up with the budget for the space program in the early 50's and 60's. They had to create a huge number of things that did not exist in order to put a man on the moon. From things as mundane as food and drink and holders that could be used while weightless to as science fictiony as computers small enough to fit in an Apollo space craft. Somehow they managed to not only do all of that, but to budget for it as well. Not only that, all of that R&D was very good for the economy, returning, depending on who you believe, as much as $7 to the economy for every dollar spent.
In my universe I'm perfectly normal, it's not my fault you don't live in my universe.
9/11, 3-4 stolen lear jets evading 1-2 F-16s, ground hugging L-39s, heat seaking shoulder mounted SAMs aimed at elevators climbing the cable, Sharks with friggin laser beams (mounted in van filled with salt water) ... ?
One man's lightening bolt is another man's elevator power source.
One unlikely problem could be capturing the public's imagination. "When we actually start launching this it's going to be kind of boring," Dr Edwards said. "There's no smoke, there's no pillars of fire and there's no loud rumbling noises. There's just this thing that slowly ascends the ribbon into space."
This just means we have to reverse the viewing of the 'launch' to be from a camera mounted from the object. It'd be really neat to see the world as this climbs up above it.
As for tourists, I imagine this could put that miniscule 'Space Needle' to shame.
bug.gd: error search engine. Humanity working together to solve all errors.
The estimate of 7 billions $ seems very, very, underestimated.
And I suppose all known NASA locations are not consider as potential site to build this escalator, most of them are much more to near regions where tropical storms are likely to happen. Because, what would happen to a nice 1 meter large, paper thin, 100 000 km long light weight ribbon under a tropical storm? For sure, it will be hard to align the laser beam on the vehicles.
Achille Talon
Hop!
Just because it's made of carbon doesn't make it easy to build. I don't know of any organism that makes diamond either (although if I did, I probably wouldn't tell anyone anyway :-) ).
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"For these very obvious reasons, the air space around the elevator would be restricted and so would the sea lanes. Remember, this though would be far out in the Pacific, very very far from anywhere (hundreds of miles - not a 15 minute jog). It's not like you could sneak up on the thing.
I'd like to see those Lear Jets that could evade F-16s in any air space, let alone over the open Pacific. It's not like they can pretend to be Clint Eastwood in Firefox and dive down a canyon or something. Shoulder mounted missiles? Fired from where? A guy bobbing in a life preserver who swam out there?
Besides, terrorists could blow up airplanes, mine harbors, poison water supplies, gas subways, fly planes into more buildings, put truck bombs on major bridges or in garages of major business buildings... If we're going to worry about the sky falling, we might as well just hang up our guns and slink off into the sunset.
Quoth he
"It's all academic anyway..."
You'd be basically creating the largest "short" ever.
Not unless you made it out of superconducters! Even the best conductor we know is going to have a significant amount of resistance along the kinds of lengths we're talking about.
And depending on the exact carbon nanotube technology they settle on, the elevator won't be all that conductive to start with... it could very well end up being less conductive than the air around it...
I am disrespectful to dirt! Can you see that I am serious?!
There are only two practical floors for average people. Earth and GTO. Getting off before GTO would send you plummeting back to earth. Getting off after GTO would send you to either elliptical orbit or even escape velocities to Moon, Mars etc. but that is not for an average person.
Oh lord not this again. Yes, we must not do anything that may be a target for terrorists. Dont drive your car because there might be a car bomb. Dont fly becuase the plane might be hijacked. Tell you what, why dont you hide under your bed while the rest of us continue on with life and the building of civilization.
I'm a programmer, I don't have to spell correctly; I just have to spell consistently
"the floating base platform would be placed hundreds of miles from aircraft routes and shipping lanes and would be in a region of the sea where storms, lightning and high waves are rare." I understand that they are concerned about access, but in reality it's a waste of time and money. Any sufficiently useful transport technology has historically generated growth and traffic around itself. Instead of having to deal with restricted and obscure access routes, these elevators should be dropped into the major trade centers of the world. Ports bring boats, airplanes, highways and trains all into one place. The next logical step is to include access to space. If the space elevator is built in the middle of the pacific ocean, the next great challenge will be to supply a floating airport and direct shipping routes...
In other words, "Oops, I forgot about that..."
Er, no.
In other words: "I do not know the precise location where it crashed (how could I?). I know it is somewhere around the east coast of the U.S.A. because that is where all the action was going on, and I assume that it crashed in water because that would explain why no one found any piece of it."
1) Why would the terrorists fly the plane over water? There are no buildings to hit in the middle of the ocean.
2) Why have no Air-traffic controllers come forward to say they saw the plane over (as you say) the water? In fact, as I recall, the ATCs had the plane on radar up until close to the Pentagon hit.
3) Why has no one come forward to say they saw the plane blow up/crash. Unless it was FAR out to sea (see #1- WHY?), a mid-air explosion and crash would be easily visible from shore. In addition, the East coast is the most heavily populated part of the US, so it's unlikely to have been missed.
4) Why has no debris been found on the beach? No luggage, flotation devices, oil slicks, bodies....
5) What about the jet pilot(s) who shot the plane down? Ordered to remain silent, you say? People have disobeyed orders for less than the guilt caused by killing a few hundred people.
6) If the plane was hijacked, and flown off course for so long, how come none of the passengers pulled out a cell phone (like flight 90) and phoned home? "Hey, we're supposed to flying west, but we're over the Atlantic and there are fighter planes all around us..."
7) Again, why the cover-up? To 'save' one General's reputation?!? Insane.
Once more- apply Occams razor. WHich is more likely:
A plane crashes into a building in such a way that it (the plane) is incinerated.
or
THOUSANDS of people, from Air Traffic Controllers, to beachcombers, to military pilots, to the passengers on the very plane itself, are in on a MASSIVE conspiracy to hide the truth.
Really, now.
Actually you do. It's the whole point of having the cable there at all. You need something to push off of. The only alternative is to throw stuff backwards really fast. The purpose of building a cable is to avoid that method.
Finally! A year of moderation! Ready for 2019?
Remember, the Pentagon is a miliatary structure and was MEANT to withstand attack. It's a VERY solid structure.
I would dare say it's built like a fort.
-------- -------- Support Wesley Clark for president!!!
It has some obvious mistakes like:
> At about a third of the way along the cable -
> 36,000km from Earth - objects take a year to
>complete a full orbit.
Should be : 24 hour to complete a full orbit
>The biggest hazard could be space junk, but Dr
>Edwards said the floating platform would be moved
>around to steer the cable out of the way
Hmm. I would like to see them:
1. Tracing space junk ~0.01-1mm in size
which flies around with a speed ~10km/sec.
2. Moving platform fast enough on the ground
to avoid collision at the altitude
~200 -1000 km . At those altitudes junk
has the maximum density.
> Edwards, who estimates it would take about $7bn
> (4.4bn) to turn the concept into reality
This thing should weight no less then ISS.
Most of it flies much higher orbit:
36,000-100,000km compare to ~500km for ISS,-
READ: more expensive to get there.
Now check the web about ISS price tag.
Reminds me the story with cheap Space
Shuttle for $5.6 +/- 1.0 bn.
Either article is bad or this guy is full of @#$%.
Pessimist is a well informed optimist.