Space Elevator on Mars: Feasibility, Design Issues & Vibration

[sid_galt]

How feasible is the idea of making a space elevator on Mars? What are the design issues?

Will the swaying and vibration problems be of the same magnitude as earth?

 

[russ_watters]

Well, in terms of what the structure would look like, it'd be a lot smaller and simpler than building one on Earth becaues of the weaker gravity. But to actually build it requires sending a mining equipment and a steel (or carbon nanotube) mill to Mars. Not in my lifetime...

 

[Danger]

I'm not that familiar with the elevator concept, despite the input from previous threads. Two things would definitely make the idea more workable on Mars than on Earth. One is that the structural strength and motive power needn't be as high because of the lower gravity. Secondly, the atmosphere is so thin that even a very high-speed wind would have very little force behind it.

 

[LunchBox]

I've seen analysis that shows we could build a space elevator on the moon today, as in right now, with Kevlar. The only issues are getting that much Kevlar and supplies TO the moon (along with the fact that you would have to get TO the moon in order to "launch" on the space elevator FROM the moon).

As for Mars... I don't know.

Cheers...

 

[Ophiolite]

The issue is treated in a fictional setting by Kim Stanley Robinson in his Mars Trilogy. Those of you familiar with his work will know it is well founded scientifically, with a minimum of poetic licence.
My recollection is that he postulates the use of carbon nano-tubes, which are under consideration for an Earth sky-hook. I don't recall if it was necessary to have that degree of tensile strength for Mars, or if he just wanted to use the most advanced material that was 'real'.
I do recall there was an issue with the orbit of either Phobos or Deimos, which would have struck the cable unless it had been placed in a constant oscillation, timed to avoid the moonlet each time it passed.

 

[sid_galt]

Thank you for the replies

My team has to develop a design for a space city complete with the method of construction and what will be in it, etc. in a month. The estimated cost and time for construction has to be reasonable whatever that means.

The scenario is 2050.
I was looking for a way to launch finished products of aluminium into space after construction on Mars.

I do recall there was an issue with the orbit of either Phobos or Deimos, which would have struck the cable unless it had been placed in a constant oscillation, timed to avoid the moonlet each time it passed.

I read about it. It is an issue. But will Phobos really cut across the space elevator multiple times in a few days or weeks?

 

[Ophiolite]

The elevator has to be in equatorial orbit and Phobos revolves more or less in the orbital plane, in just under eight hours. (And the Martian day as you know is a little over twenty four hours.) So there will be frequent occasions when it comes very close to the cable: certainly often enough for it to be a problem that must be addressed.
You may wish to check out this site: http://www.liftport.com/forums/index.php?
It's a discussion forum devoted to space elevators! [Shoot, if they have one for space elevators, they must have one just for talking about goldfish.]

 

[russ_watters]

...along with the fact that you would have to get TO the moon in order to "launch" on the space elevator FROM the moon...

Yes, but of course you know that going up is only half the reason to have an elevator.

 

[laymicah]

well i think the best idea would be to use the large amounts titanium from the moon to build the space elevator then launch it from there. you would have to build a moon base but we should anyway that way we can launch with less expense and less gravity also using the orbit of the moon to sling shot spacecraft into the new frontiers...

 

[Bob S]

I hate to be a party-pooper, but somewhere along the way, we have to start thinking about improving the efficiency for photosynthesis of food. We are still using the same photosynthesis cycle (Calvin) the ancient Egyptians were using 5,000 years ago, except 'breeding' plants has given us better seeds, combined with fertilizers and tractors (instead of water buffalo) to give us better productivity and yield. At present, only about 0.1% of sunlight on an acre of wheat gets converted to calories. The inhabitants of the Biosphere in southern Arizona could not raise enough food on half an acre to feed themselves adequately. The sunlight on Mars is only half as bright as here on Earth. Did you include agriculture in your Space City design?

 

[Danger]

And this has what to do with an elevator?

 

[RonL]

And this has what to do with an elevator?

We won't be going up on it anytime soon.

 

[DaveC426913]

well i think the best idea would be to use the large amounts titanium from the moon to build the space elevator then launch it from there. you would have to build a moon base but we should anyway that way we can launch with less expense and less gravity also using the orbit of the moon to sling shot spacecraft into the new frontiers...

You don't launch a space elevator*, you extrude it in place.

A space elevator* has a cable going down the surface and a cable going up into "high orbit" for balance. Your central platform in low orbit is both the station and the extrusion machinery. You start making 2 cables at the central station and feed it out up and down at the same time. Once it's long enough, you tie it off at the bottom, and you're done. You can now ditch the extrusion machinery or leave it on standby.


*space elevator is a functional term - but magic beanstalk is way more appropriate and poetic. Just like Jack did - climb the beanstalk up into the clouds. When you're above the clouds, you simply step off.

I really wish**, before this technology becomes too popular, that 'beanstalk' overtakes the ugly 'space elevator' in popular termonology.



**Then again, I always thought that, while twoonie was an OK name for the Canadian 2 dollar coin, doubloon was even better. but it never caught on***.


***In the same way Beta VCR never did.

 

[Danger]

**Then again, I always thought that, while twoonie was an OK name for the Canadian 2 dollar coin, doubloon was even better. but it never caught on***.


***In the same way Beta VCR never did.

I voted (not like it counted) for Doubleloon, but I'm quite acclimated to the Twoonie moniker. I also still have 3 Beta machines and probably 150 tapes for them.

 

[Who Am I]

There is one complication about Mars that we lack here on earth: a rotational wobble due to lack of a real moon. Mars has a couple big asteroids circling it that we call moons.

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

If you all want substantial information on the space elevator, then go here: http://www.liftport.com/

I think that when we get a space elevator here on earth, getting one onto Mars won't be such a hastle. We'll be able to haul up many tonnes of material on our elevator, then we could ship an entire biosphere to orbit Mars and drop a space elevator there. This could happen in the lifetime of today's younger generation. And because life extension might be happening soon, you might experience things you never knew you would be around for.