Space ElevatorLinsen86 - 6 Answers
NASA pledged $4m towards a series of challenges that would show whether or not a space elevator is feasible. With the recent developments in carbon nanotubes and ceramic material development, it's looking more and more likely. The big hold up right now is the material for the cable.
There are a lot of websites out there on the topic. Personally I believe we will be able to do it by about 2020, but whether or not anyone will be willing to spend the money that will be needed is another question.
A great site for more information is the space elevator blog - just google it. You'll see that there are upcoming events, including the European Space Elevator Challenge in June this year and the 2011 Space Elevator Conference in August.
A space elevator is currently and for the next 500 years impossible!
Thanks to the etchnological demands.
1 - Perforce, the object to which the elevator leads will have to be "geo-stationary".
meaning 36,000 km "up" on the sky.
2 - For simplicity, it can be 36000 up and yet geo-stationary only if it is directly above the equator.
Any orbital inclination other than that will mean the object in orbit will describe a north south
range-bound linear oscillation from earth based observers point of view.
3 - There is NO known material that can be commercially cheaply made that will "hold" any object of
reasonable tonnage, "in place" 36,000 km away.
We have to think of the self weight of the "cable" and how it can be strong enough and light
enough to support the weight of the elevator and itself.
4 - The moment the satellite is anchored to the cable, the enormous self weight of the cable will
tend to pull it down!
5 - No satellite is rock steady in its orbit and even geo-stationary ones have to "fire control rockets"
from time to time to maintain position against "drift".
For a cable 36,000 km long, a drift of a few meters would constitute tensile stresses diffficult to
One may have to indeed abandon a "cable" approach altogether in view of all the above.
Instead one can easily imagine spaceships (elevators) riding microwave beams. Microwaves can transmit power.
If the elevator captures that transmitted megawatts of power, and converts into lift by any means, we are through.
Until then, such things can be only made by Zarkov of Flash Gordon & Dale fame.
I remember reading about this in a science fiction book by Arthur C. Clarke, "The Fountains of Paradise". That's worth reading, if you're in to science fiction.
I think it will be possible to have a space elevator from earth to a geostationary satellite, perhaps in the next 100 years but I think something better might be invented before then. I really hope we have alternatives to rocket travel. So many people would love to see space but it really isn't practical for all of them to get there using rocket power.
A space elevator would be a fun thing to do, but I doubt that it is possible. There is no way to support a structure that tall to enter into space.
The thing that we might see in our lifetime is not a space elevator, but a space trip. A space trip where you pay money to take a short trip into space. Maybe in the future they will be able to have like a space hotel where you can spend a few nights.
I think that some sort of space travel for regular citizens will happen in my life time. It will be cool when it comes out!
I am not sure what they might call it, but one of my friends from my high school era is working for a company that is developing a private space travel service. He has sent me some fascinating details about their test trips into space. He says they are pretty certain that space travel will be available to the general public within less than 10 years. Well, at least for those who can afford it. It is likely to be well beyond my budget....
Anyone more optimistic than Isisla29 about this? Just curious, I enjoyed his answer, but I think 500 years is a long time!...