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Author Topic: Is it possible to make a lift/elevator to get into space?  (Read 14010 times)

Offline acecharly

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Also is there a way of harnessing solar power, to power the lift?

any thoughts are welcome.

Cheers

Ace


 

Offline Pmb

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #1 on: 31/03/2012 16:01:51 »
Also is there a way of harnessing solar power, to power the lift?

any thoughts are welcome.

Cheers

Ace
Yes. It's possible and in fact NASA has it as one of their goals. See http://science.nasa.gov/science-news/science-at-nasa/2005/27jul_nanotech/
 

Offline CliffordK

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #2 on: 31/03/2012 19:26:04 »
Space elevators have been discussed on TNS numerous times.
http://www.thenakedscientists.com/forum/index.php?topic=42683.0
http://www.thenakedscientists.com/forum/index.php?topic=40657.0
http://www.thenakedscientists.com/forum/index.php?topic=36371.0
http://www.thenakedscientists.com/forum/index.php?topic=3574.0

Theoretically it is possible to put an object in orbit, either geostationary, or perhaps even a lower orbit, and let a cable descend from that object to Earth for use as a space elevator. 

It would be a monumental engineering task.  It would take materials stronger than any material than we can make more than ¼ inch long.  For a geostationary orbit, the cable would need to be 35,786 km (22,236 mi) long, or perhaps a bit longer.  I.E.  a cable the length of the entire circumference of the Earth.  If the material to build the cable was to be made on Earth and transported to space, it would take more space launches than all the space launches to date. 

Catastrophic failure of the system not only would mean the loss of a multi-trillion dollar cable, but could cause massive devastation on Earth below.

As far as powering the climbers, current plans indicate using some kind of beamed energy which could include reflected solar energy, although one may also choose to use some kind of conductive cable system, and electric power, perhaps solar power generated at the space station above, without atmospheric interference.
 

Online syhprum

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #3 on: 31/03/2012 19:39:08 »
I don't think we should worry about how the elevator will be powered by the time it is built portable nuclear fusion power plants will be as common as toasters.
 

Offline CliffordK

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #4 on: 31/03/2012 20:24:28 »
by the time it is built portable nuclear fusion power plants will be as common as toasters.
Is that about the time when Pigs will be Flying?
 

Offline yor_on

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #5 on: 01/04/2012 09:28:21 »
Ahem, a most excellent link Clifford :)

Can't help but cite it.

"John Steinbeck was told by his professor that he would be an author when pigs flew. When he eventually became a novelist, he started to print every book he wrote with the insignia "Ad astra per alia porci" (to the stars on the wings of a pig)"
 

Offline channel

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #6 on: 13/04/2012 16:18:06 »
I've read somewhere that space elevator made of a conductor ( such as nanotubes ) could produce deadly currents and epic arcing.

Is that true?

 

Offline CliffordK

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #7 on: 13/04/2012 18:59:58 »
Carbon (graphite rings) is a good conductor, but not as good as many metals.

I could only imagine a space elevator in a thunderstorm.  I don't know if the elevator itself would generate static electricity.

There would be a couple of ways to making an elevator.  One might be a floating end, perhaps 30,000 feet, or 10,000 meters, so that it would clear the mountains, and reduce atmospheric drag.  At which point it might concentrate some electricity in the cable.  One might design the cable tip to direct power surges away from the terminus structure.  It shouldn't be worse than an ordinary thunder storm on the ground.

The other option would be tethering it to the ground, in which case, it would be well grounded, and no more dangerous than a skyscraper or radio tower.  The Eiffel Tower?
 

Offline Ęthelwulf

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #8 on: 14/04/2012 06:04:42 »
Also is there a way of harnessing solar power, to power the lift?

any thoughts are welcome.

Cheers

Ace
Yes. It's possible and in fact NASA has it as one of their goals. See http://science.nasa.gov/science-news/science-at-nasa/2005/27jul_nanotech/

I have seen this before, but I have difficulty in believing such a lift can be created.

What stops such a lift being ripped apart by the centrifugal force of the Earth?
 

Offline Geezer

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #9 on: 14/04/2012 08:47:48 »

What stops such a lift being ripped apart by the centrifugal force of the Earth?


That's a bit unlikely because, contrary to popular belief, the Earth has no centrifugal force.
 
 

Offline Ęthelwulf

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #10 on: 14/04/2012 11:18:16 »

What stops such a lift being ripped apart by the centrifugal force of the Earth?


That's a bit unlikely because, contrary to popular belief, the Earth has no centrifugal force.

And why wouldn't it have a contrifugal force?
 

Offline JP

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #11 on: 14/04/2012 14:21:41 »

What stops such a lift being ripped apart by the centrifugal force of the Earth?


That's a bit unlikely because, contrary to popular belief, the Earth has no centrifugal force.

And why wouldn't it have a contrifugal force?

Because there's no such thing as centrifugal force.
 

Offline Ęthelwulf

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #12 on: 14/04/2012 20:13:22 »

What stops such a lift being ripped apart by the centrifugal force of the Earth?


That's a bit unlikely because, contrary to popular belief, the Earth has no centrifugal force.

And why wouldn't it have a contrifugal force?

Because there's no such thing as centrifugal force.

Wait a minute you guys, are you saying this because it is a ficticious force? You know, a false force... this is well known. It is sttill generally regarded as a real force however from certain frames of reference.

http://en.wikipedia.org/wiki/Centrifugal_force

Gravity is a psuedoforce as well in many theories.
 

Offline Geezer

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #13 on: 14/04/2012 21:04:27 »

Wait a minute you guys, are you saying this because it is a ficticious force? You know, a false force... this is well known. It is sttill generally regarded as a real force however from certain frames of reference.


It may be well known, but it's frequently misunderstood. Only real forces rip things apart.
 
If you apply the frame of reference argument you also have to ignore the rotation of the Earth, in which case it is just a force that has no business being called centrifugal. If you are aware of the Earth's rotation, you know there is no centrifugal force.
 

Offline Pmb

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #14 on: 14/04/2012 21:55:43 »
Quote from: Ęthelwulf
I have seen this before, but I have difficulty in believing such a lift can be created.

What stops such a lift being ripped apart by the centrifugal force of the Earth?
The material that the lift is made of must be able to support a large amount of stress.

Regarding centrifugal force: such a force falls under the classification inertial forces. The strength of such a force is velocity dependant and therefore depends on the particular frame of reference in which it is evaluated. This is different than other forces such as the electromagnetic force. As far as the rest of this thread goes, I got into that debate on many occassions. According to General Relativity, the gravitational force is an inertial force. It's quite an involved discussion so I made this web page to exlain the concept of inertial forces = gravitational forces. Please see http://home.comcast.net/~peter.m.brown/gr/inertial_force.htm
 

Offline CliffordK

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #15 on: 14/04/2012 22:20:12 »
I disagree with Geezer on the "realness" of the Centrifugal Force.

However, down on Earth, the centrifugal force is low.  I.E.  People don't get flung off of the equator. 
The centrifugal force is what is keeping the satellites in the sky. 

For the space elevator cable, the centrifugal force is what will keep the skyward end in the sky.  However, it will not be applied at a point, but as a continuum down the cable (although a counterweight would be at a single point).

But, the weight of the cable (likely tapered) will still be very significant.

Assuming the cable extends into the troposphere, I would be concerned with sheer factors with jet streams and weather phenomena. 
 

Offline Geezer

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #16 on: 14/04/2012 23:12:50 »
I.E.  People don't get flung off of the equator. 
The centrifugal force is what is keeping the satellites in the sky. 

For the space elevator cable, the centrifugal force is what will keep the skyward end in the sky.  However, it will not be applied at a point, but as a continuum down the cable (although a counterweight would be at a single point).

But, the weight of the cable (likely tapered) will still be very significant.


There is no "flinging off". If gravity quit working, you would travel in a straight line tangential to the Earth's rotation.
 
Depending on your view of what gravity is, if you view it as producing a force, it is a centripetal force that causes you to not follow a straight path as described by Newton's First Law of Motion. This is important, because the force acts towards the Earth, not away from it. 
 
Statellites are not kept in the sky by any force. They are in the sky by virtue of their momentum. Gravity applies a centripetal force that keeps them in orbit and prevents them from heading straight off into space.
 

Offline Pmb

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #17 on: 14/04/2012 23:34:27 »
I disagree with Geezer on the "realness" of the Centrifugal Force.
In my opinion his comment Only real forces rip things apart. is misleading. Consider a body whose spatial extention is large enough such that the tidal forces exerted on it by the gravitational field is significant. The gravitational force on the body virtually zero. However the gravitational tidal force is significant. In this case the 4-force on the body is zero but the gravitational 4-force on it due to the gravitating field (i.e. the tidal force) is zero.

A good example of this is when a star is torn apart by gravitational forces as it falls into a black hole. The tidal forces on it are zero but the gravitational force is zero.
« Last Edit: 15/04/2012 00:07:20 by Pmb »
 

Offline CliffordK

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #18 on: 15/04/2012 00:29:44 »
There is no "flinging off". If gravity quit working, you would travel in a straight line tangential to the Earth's rotation.
Ignoring, of course, that without gravity, there would not be be an atmosphere, and the Earth would disintegrate. 

But, in your day without gravity.  Those people smart enough to tether themselves to Earth (for example tied to a tree), wouldn't find themselves flattened against the Earth with their rope at a tangent, but rather, they would find themselves hanging out at a perpendicular to Earth's rotation, at the end of their rope.  At the Equator, they would be hanging perpendicular to Earth.  At the 45th parallel, they would be hanging at a 45 degree angle from the surface.  You could say that the tree that a person is tied to is exerting centripetal force on that person.  Yet, what would you call the force the person is exerting on the tree, tending to pull out the roots?  And, what direction are the roots pulled out?
 

Offline Geezer

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #19 on: 15/04/2012 01:01:08 »
Yet, what would you call the force the person is exerting on the tree, tending to pull out the roots?  And, what direction are the roots pulled out?

Well, according to Newton's third law (which hasn't be repealed AFAIK), you would call that the reaction to a centripetal force.
 
Things travel in straight lines unless a force acts on them. If you want to believe that things go around in circles all by themselves, that's entirely up to you.
 

Offline Ęthelwulf

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #20 on: 15/04/2012 02:04:49 »
I agree with Clifford, I agree only partially with Geezer.

I feel compelled to tell everyone no one understands what actually causes Inertia. Einstein had idea's based on Mach's principle that maybe inertia was caused by every mass in the universe. This still seems like a very good candidate. Let us a assume for a small instance that you had a pole connected to a ball of mass which was spun at very high speeds. You would actually find that the pole which extended beyond such a mass would be deformated due to inertial forces which we call the centrifugal force. This is because the pole which extends the object is in fact always trying to defeat being accelerated. The same would be found on Earth, I presume. If an elevator hit the heavens, the actual elevator which leaves the earth's atmosphere would constantly be fighting the inertial forces. The object is not accelerating from it's frame of reference but will experience ''tidal like forces'' influence by the moon and it's own experience of being spun from the earth's frame of reference.

Maybe I am wrong, but it all seems pretty much straightforward.  If someone said to me that the centrifugal force was not real, I'd challenge them also then to explain gravity as psuedoforce. Does that mean gravity is not real? You may challenge this against the Einstein Cartan Theory of gravity, which explicitely see's gravity as a psuedoforce: and with my experience, the EC-theory of gravity should be expected to be real, since it is the full-poncair representation.
 

Offline JP

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #21 on: 15/04/2012 02:15:25 »
I think if everyone called it the centrifugal pseudoforce instead of the centrifugal force, there wouldn't be an issue.
 

Offline Ęthelwulf

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #22 on: 15/04/2012 02:29:41 »
I think if everyone called it the centrifugal pseudoforce instead of the centrifugal force, there wouldn't be an issue.
Well, maybe.

It is still quite a real force from certain frames of reference.
 

Offline Pmb

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #23 on: 15/04/2012 03:30:46 »
I think if everyone called it the centrifugal pseudoforce instead of the centrifugal force, there wouldn't be an issue.
That's like saying that if everybody in the world became a Muslim then we'd have world peace.
 

Offline Ęthelwulf

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #24 on: 15/04/2012 03:34:13 »
I think if everyone called it the centrifugal pseudoforce instead of the centrifugal force, there wouldn't be an issue.
That's like saying that if everybody in the world became a Muslim then we'd have world peace.

Yes, well I am sure the Muslim faith is also the correct faith from certain frames of reference ;)
 

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Re: Is it possible to make a lift/elevator to get into space?
« Reply #24 on: 15/04/2012 03:34:13 »

 

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