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Space elevator a reality soonish

My first question is...

What's to stop if from slowly coming closer and closer towards the planet, until finally burning up in the atmosphere?
 
ImpyTimpy said:
My first question is...

What's to stop if from slowly coming closer and closer towards the planet, until finally burning up in the atmosphere?
Click to expand...
Good question, as I undestand it, the same way you swing a rock around on the end of a string and it defies gravity and stays level with the plane of rotation. The elevator would need to be at the equator for this reason.

Ask me another :)
 
OK Squishy - what music will they be playing on the way up?

If it is several hours of 'Kenny G', then I don't think the space program will last...

Athon
 
How will they stop all the GPS, weather, communication and spy satellites from slamming into the elevator tower?
 
ceptimus said:
How will they stop all the GPS, weather, communication and spy satellites from slamming into the elevator tower?
Click to expand...

It will have a light on the top so that they can avoid it.:p
 
ceptimus said:
How will they stop all the GPS, weather, communication and spy satellites from slamming into the elevator tower?
Click to expand...

According to the site, they would just swing the end around to different locations. It says they would have to move it frequently to dodge satellites and debris.



Arthur C. Clarke's 2069 (the third Odyssey book) ended with the idea that humans had built many space elevators. But his idea was to have "firm" elevators, made from diamond that was blown from the core of an exploding Jupiter.
 
I mentioned this in another thread . static motor...
The end of the "cables" are at a geosyncronious orbit with a terminal attached so there's no tortional or centrifical force involved.

A secondary affect is that the hugh electrostatic difference can be coupled as a generator ( in fact as corbon is a resistive conductor the"cables" themselves can be the transmition lines)

And I believe the science of elevator music has gone as far as far as late 80's rock so.......
 
If evil (and I mean evil) terrorists blew up the ground base, severing the ribbon, would the station fly away or crash and burn into the atmosphere??

(Because, as we all know, Sci-Fi is about cool explosions and laser battles)
 
According to one design I read about, the end of the cable would just hover there. Perhaps it might blow in the wind. Other designs would have the cable fly off into space. In order to make it collapse to Earth, one would have to destroy the counter-weight in space.

And then it would wrap around the Earth a few times, destroying anything at the equator. Suddenly, equatorial property doesn't seem so valuable.

Of course, if such a thing happened, they might release he ground anchor as well, to let it fly off. I'm not sure if that would work.
 
Yes, well what geosync orbit is an equilibrium point between centrifugal force and gravity. The system is closed and requires no counter-weight. You would of course put a terminal at the space side for both maintenance and egress of freight. It would have no inertial effect on the system ( if accounted for).

If you cut all the "cables" earthside the have approximately the same force applied as you do standing upright, if you lost the terminal ...same condition in either case you would have quite a while before the system looses equilibrium- so you could affect repairs. If I'm not mistaken the highest implied force is at the middle of the "cables", most of that being atmospheric drag on the lowest quarter.and centerifical force at the top quarter . Lots of math there maybe someone wants to take a shot...I don't =). only other thing I can say in defence of the idea is that's so balanced that I can't see the kind of instantaneous catastrophic failure associated with plane crashes or train wrecks. It is a super massive inertial system with fairly static properties ( not including the induced voltage thing)
 
In the article, they relate how the ribbon will be some 100,000 kms long, way past the altitude of the geosynchronous orbit. I'm somewhat puzzled in regard to why the ribbon should be longer than the 36,000 kms or so of geosynchronicity.

Suggestions?
 
Well, for a start, it's the center of gravity of the whole contraption that needs to be (at least) in synchronous orbit. So you need a counterweight out beyond the Clarke orbit, to balance the part that is below it.

Also, it is desirable for the c.g. of the whole thing to be slightly further away than the Clarke orbit, as this enhances the 'rock on a string' effect, helping to keep the ribbon tight, and compensate for the tilting effect caused when a mass ascends or descends the elevator, so needing to gain, or lose angular momentum (aka eastwards velocity).
 
ceptimus:
Well, for a start, it's the center of gravity of the whole contraption that needs to be (at least) in synchronous orbit. So you need a counterweight out beyond the Clarke orbit, to balance the part that is below it.
Click to expand...
But it is my understanding that the ribbon is essentialy massless compared to the "counterweight".
Also, it is desirable for the c.g. of the whole thing to be slightly further away than the Clarke orbit, as this enhances the 'rock on a string' effect, helping to keep the ribbon tight, and compensate for the tilting effect caused when a mass ascends or descends the elevator, so needing to gain, or lose angular momentum (aka eastwards velocity).
Click to expand...
How does one maintain tension in the ribbon when the counterweight is in an orbit which revolves much slower than once per day?
 
Think of our moon. It's a quarter of a million miles away, and takes about a month to go round once. If you were to lassoo the moon, and tie the end of the rope to a peg on the Earth's equator, you'd be trying to swing the moon around about 29 times faster. Don't you think that would put a fair bit of tension in the rope?

;)
 
c0rbin said:
If evil (and I mean evil) terrorists blew up the ground base, severing the ribbon, would the station fly away or crash and burn into the atmosphere??

(Because, as we all know, Sci-Fi is about cool explosions and laser battles)
Click to expand...

The ribbon is under tension--if you blew up the ground base the lower end of the ribbon would snap up a bit; the ribbon as a whole would wander slowly westwards. After rebuilding the ground base, you'd have to launch a suborbital craft to dock with the remnants of the tether; this would splice the cable and eventually redock with the rebuilt ground base. The rebulit ground base would haul the tether back down and you're back in business.

The ribbon is probably going to be black--i don't imagine it would fare very well in a laser battle.
 
"Well, for a start, it's the center of gravity of the whole contraption that needs to be (at least) in synchronous orbit. So you need a counterweight out beyond the Clarke orbit, to balance the part that is below it.

Also, it is desirable for the c.g. of the whole thing to be slightly further away than the Clarke orbit, as this enhances the 'rock on a string' effect, helping to keep the ribbon tight, and compensate for the tilting effect caused when a mass ascends or descends the elevator, so needing to gain, or lose angular momentum (aka eastwards velocity)."

Ummm.. I completely disagree
The idea of any machine (motor) is to get the maximum output with the greatest efficiency at the least cost in terms of fuel and degradation due to ware.
Why would you want to stress the proposed system with it taking on the inertial properties of " a rock on a string"?, especially when the only benefit would be to fling cargo??
The geosync orbit has so many more benefits in terms of movement of cargo and lack of stress , your alternative seems unreasonable. With the geosync orbit it is a self aligning system, you idea introduces a huge calculus of force variables that need not be addressed. There is no CG per se in this system ( as the forces are equalized) unless one exceeds the limits of the proposed system . I believe your postulates not only wreak the idea of this system but introduce a universe of incalculable effects that need not be accounted for in the static model.
 
Adressing the 'crashing into stuff' problem...


The outer atmosphere is a pretty big place, and it keeps getting bigger the farther you go. So avoiding satellites can't be THAT hard.
 
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