# Japan to build Space Elevator

Discussion in 'General Science & Technology' started by madanthonywayne, Sep 22, 2008.

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1. ### Uno HooRegistered Senior Member

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Many people who are serious fans of an orbit elevator haven't figured out that it takes a specific minimum amount of energy to get from the surface into orbit. No matter whether you ride a rocket, an orbit elevator, a flying saucer borrowed from A51, or whatever.

The minimum amount of energy is a number only available in perfect circumstances. Some modes of elevation are more efficient. Some modes are less efficient. It all goes back to fighting against gravity.

Gravity is constantly pulling down at one gee. If your elevational motorvator is boosting you up at 1.001 gee gross then you are wasting most of your energy just to prevent falling back down. If your elevational motorvator is boosting you up at net 10 gee then you are only wasting one gee worth of energy compared to the 11 gee of gross energy expended. Eleven gee minus one gee to null gravity equals 10 gee going up. Get it?

One gee just lets you hover while burning up energy. 1.001 gee burns up one gee to not fall back down leaving you with only 0.001 gee to go up. 11 gee gross burns up one gee to not fall down leaving you 10 gee to go up.

Careful mathematical examination of the situation shows us that the most efficient way of going up is the way that provides the greatest gee acceleration upward. That way the chronic one gee tax paid to the planet gravity becomes less important.

Ok. Bottom line time. it doesn't matter if you go up in a rocket, a flying saucer borrowed from A51, or even an orbit elevator. Whatever is the most efficient way is the most economical, therefore , in the opinion of some bean counters , the best way.

Question: Does the fantasized orbit elevator offer the greatest fantasized acceleration upward and therefore the most efficient way to get into orbit?

Helpful hint: Hell no.

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3. ### PeteIt's not rocket surgeryRegistered Senior Member

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If you're sitting on rockets. If you're sitting on a chair (or hanging off a cable) on the other hand, you can 'hover' at one gee without expending any energy at all.

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5. ### EnmosValued Senior Member

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Would there be a space station on the other end ?

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7. ### Uno HooRegistered Senior Member

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In all the excitement, you seem to have lost count yourself. So, ask yourself one question, punk," Is the purpose of an pseudoscience orbit elevator to hover indefinitely 3 feet off the ground without burning up energy?".

8. ### MetaKronRegistered Senior Member

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Uno, it's not energy that gets a rocket off the ground. It's momentum. There is not even a direct mathematical relationship between momentum and energy.

A vehicle that rides a cable up and down doesn't even need to carry its own energy, except as backup batteries. Energy can be beamed up to it on laser light or microwaves. It only needs energy because it can generate momentum by pushing against the cable. No mass has to be thrown away. No dangerous flames or particle beams need to be generated.

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10. ### PeteIt's not rocket surgeryRegistered Senior Member

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I'm afraid I can't answer your query - I don't know of the "pseudoscience orbit elevator" of which you speak. I wish you luck with finding an answer elsewhere.

11. ### Uno HooRegistered Senior Member

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But Pete, if you are just practicing your happy pastime of ( hanging off a cable ) then you are not only without expending any energy at all, but you are also not climbing the cable to the stars, not moving up the way to the orbital elevator satellite.

What is the point you of hanging off the orbit elevator cable, even if it might be great fun for you, if you are not moving up to the stars?

Have you once again stopped being able to tell the difference between your dream and waking reality?

12. ### PeteIt's not rocket surgeryRegistered Senior Member

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I'm glad you've realized your earlier mistake:
Perhaps you can now understand why climbing a cable is much more energy efficient than sitting on a rocket.

13. ### NasorValued Senior Member

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This has already been addressed at length. Most likely the cable would break. The cable below the break (a few tens of thousands of feet, or whatever) would fall downward, while the other thirty five thousand or more km of cable above the break would simply hang there waiting for you to reattach something to it. I suppose you would have to send up a blimp or something to do the repair work.

Last edited: Oct 28, 2008
14. ### salvationRegistered Member

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anti grav technology is far more desirable and cheaper than any space elevator.

by removing the affect of gravity you remove the need for a space elevator,instead of an elevator you have a anti grav platform that can carry large amounts of matter into orbit.

we already have anti grav technology but its all either done in black ops or if developed in public sphere bought by them.
i remember a scientist who developed an anti grav technique using the electrogravetic effect in a bose einstien condensate where the orbits of the electrons are easily controlled,straight away she was pretty much forced to hand her work over to darpa.

15. ### XyleneValued Senior Member

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Put the entrance to the space elevator up about 10 miles above the Earth's surface, perhaps, and above most of the atmosphere so it's not affected by storms. Then get one of Richard Branson's spaceplanes to fly up there and dock for offloading. Just a suggestion...

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16. ### NasorValued Senior Member

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You could do that, but for most cable designs wind in a non-issue. The cable is at least 35000 km long. Only the first 10 km or so will experience any significant force from wind, and the wind won't do much. The deflection in the cable caused by the wind will probably be much less than the deflection caused by angular momentum issues as cars moving up and down the cable.

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20. ### Diode-ManAwesome User TitleRegistered Senior Member

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If Japan builds a space elevator I'm going to count that as a military item, I hope something from the heavens stops them from accomplishing this.

21. ### NasorValued Senior Member

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The satellite station - if you use a design that has one - is slightly past the point of geostationary orbit, so the the center of mass for the entire cable+station assembly is right at or slightly past geostationary orbit.

22. ### SyzygysAs a mother, I am telling youValued Senior Member

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Then it is NOT an elevator.

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Actually, it is a missnomer either way....