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Science: Space: Orbit
Space-Tram   (0)  [vote for, against]
Like a space elevator, but in the x-axis

Two satellites are placed into Earth orbit at points where a carbon fiber tether between them forms a tangent to the Earth itself. So the satellites stay where they are and the Earth spins under them, the tether "slides" along the surface of the Earth (but about 1000 feet off the ground). When the tether comes by your part of the Earth a helicopter elevates your Space-Tram to the tether and you attach your Space-Tram to it. The Earth spins underneath you and later on when you are over China, you request a detach and another helicopter comes and gets you. You have just travelled to the other side of the globe for the cost of a 1000ft vertical helicopter ride.

The Space-Tram is really just like a regular tram you might find at a ski resort, but it has a special arm to attach to the tether. It also has a sofa, a bar, small kitchen, and video games to make the long ride more enjoyable.

Yes, the Space-Tram never actually goes into space. Calling it "Space-Tram" is more of marketing gimmick.
-- DeathNinja, Sep 19 2003

No reason it can't go into space as well
-- yamahito, Sep 19 2003


Very good idea if you can find some strong-enough cable (which you can’t.) I think you could do this with just one satellite and a cable hanging straight down. You would also have to make sure there were no mountains or tall buildings in the way. +
-- AO, Sep 19 2003


I think it would be hard to catch if it was just a dangling cable. The double-satellite thing gives you a nice long stretch of cable so you can take more time attaching.
-- DeathNinja, Sep 19 2003


That makes sense.

Another thing I just though of, the cable can’t travel through the air any faster than the helicopter’s top speed (probably about 300 mph). At that speed it would take about 42 hours to get to the other side of the planet.

If you used an airplane to get you up to the cable you could have it going about 2000 mph, which would reduce the trip to about 6 hours. The airplane wouldn’t have to land, it would just need to match the speed of the tram car, and then latch on from the bottom using a special docking ring.
-- AO, Sep 19 2003


//the satellites stay where they are//
The satellites will need momentum to overcome gravity, as well as moving in relation to the planet's rotation, to pull the cable with the tram.
It will take a vast amount of energy to keep the satellites in orbit, compared to the energy needed to move a non-tethered tram. However, if the cable is used as a space elevator, it might be worthwhile. You can almost balance this contraption when not in use (minimal energy). And with enough fast airplanes, you can sustain the inertia of the satellites. Or it would pull them down -- one or the other.
-- Amos Kito, Sep 19 2003


[Amos] as far as I know the energy that keeps the satellite in orbit is the centrafugal energy of the satellite and it's mass in geo-sync orbit.

[AO]- the cable strong enough would be carbon nano fibers, they figure they could build a system like this right now for a mear 6 billion.
-- SystemAdmin, Sep 19 2003


AO - how long would it take if the cable was counter-orbiting the direction of the earth's rotation?

SystemAdmin - No, they can't - the carbon nano-fiber isn't there yet. What you probably mean is that, after 6 billions' worth of investment into research, it will become possible.
-- yamahito, Sep 19 2003


How about attaching cable cars to either side of the main tram, which travel along the tether to either satellite. Voila! your'e in space!
-- EdZ, Oct 28 2003



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