Page 3 of 4

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Thu Sep 02, 2010 6:09 pm
by JamesG
Tethers or space elevators will be relatively cheap in operation, but not to set up. Beyond the materials mfg. which hasn't been figured out yet, you need a robust orbital infrastructure to build the terminal stations, counterweight, and let down the tether. None of which will be cheap. Right now you would need the coordinated approval and resources of the entire planet to attempt it.

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Thu Sep 02, 2010 10:08 pm
by Intranaut
You guys might appreciate this website :)

http://www.isec.info/

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Fri Sep 03, 2010 2:07 pm
by RickLewis
That's an interesting website. It sounds like there are space elevator groups in a number of different countries, including Japan. But is there interest yet from any commercial or governmental organisations with the resources to seriously pursue the project, like NASA?

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Sat Sep 04, 2010 12:21 am
by Intranaut
Well as far as I can understand right now, the issue with actually trying to build one is the cost and risk of it. One of the only materials strong enough to hold the tether taught is made from carbon nanotubes which is extremely expensive, you're talking about making hundreds of kilometres of this stuff on the nanoscale. The other thing is the risk of what happens if a strong storm hits elevator or even a terrorist attack; the space station or asteroid or whatever is attached on the other end, I imagine something like a space port, would fly off into space. Don't get me wrong though, I'd love to see one built! If successful it could do amazing things for the space industry.

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Sat Sep 04, 2010 12:23 am
by Intranaut
I'm not sure if it's been listed already but I think it costs something like $25000 per kilogram to send something into space on conventional rockets, with a space elevator you could lower the cost to between a hundred or a couple hundred of dollars.

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Mon Sep 06, 2010 3:24 am
by JamesG
The entire system is balanced by its centrifigual force against gravity. The ground station does not even need to be anchored to the Earth except to dampen out atmosphereic drag and as an electrostatic ground. It can even move around, it would actually be preferable to have the ground station embeded in an ocean to avoid juristicional and accident/sabotage issues.

And it would need to be 22,000km long for Earth. So you'd need many hundreds of thousands of km's worth of nanotubes or whatever else you make this "beanstalk" with. Like I said, a project for the entire world at this point.

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Mon Sep 06, 2010 6:11 am
by Intranaut
Why 22000km? Shouldn't it be in geosynchronous orbit?

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Mon Sep 06, 2010 2:25 pm
by JamesG
I mixed up my units. ~22K miles.

Yes, the counterweight has to be in geostationary orbit, either a mass there or a extension tether running even further out.

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Mon Sep 06, 2010 4:50 pm
by Colonizer
not trying to be negative here but the space elevator may not work. if its anchored ground it would be vunerable to multepule natrual ocurances. whay if a earthquack hit, herican, average lightning storm, etc. there is also man made effects such as terrorisom, miss calculation, maintanence, planes, etc. yes the elevatour would have a mandetory disstance for planes. it would need maintanence almost affter every use.the earth quacks can take out the ground station. hericans may pull the space station out of orbit or break the cord/elevator.

i do like the idea of the eleavator but there are plenty of issues...

im wondering if we can build the elevator but insted of the ground station there is one up in the air that has airports where helicopers, planes, etc. can land on. has some kind of lift to keep it up. would blimp styles work, multiple large helicopter blades(not shear what that is again). or something like that. it wont be effected by earthquacks. it can move so if hericans are heading in. but the issues with this is stability, maitanence, ordinary storms, weight, and so on.

sorry about any spelling issues

Re: Wanted: practical launch vehicle, cheap!

PostPosted: Tue Sep 07, 2010 6:21 am
by Intranaut
Something like this?

http://forums.spacebattles.com/showthread.php?t=142425


Doctor Who ftw! :geek: