Space Elevator Questions

[brand1130]

I have a few quick questions on space elevators maybe some of you could help me out with.<br /><br />1) How long would the trip be from the bottom to the top?<br /><br />2) How thick will the carbon-nanotube ribbon be in both width and thickness?<br /><br />3) Where would it be built? I'm assuming somewhere near the equator, but like, how far out to sea? Or would it be on land? Would it be visible from land?<br /><br />4) What will the transport rooms be like? Habitable, I'm assuming?<br /><br />5) Finally, if the elevator is moving so slow, does it still experience the "atmosphere" heat that space shuttles go through as they enter it?

 

[alpha_taur1]

"How long would the trip be from the bottom to the top? " - How long is a piece of nanotube? <img src="/images/icons/smile.gif" /> Sorry I couldn't resist.<br /><br />I posted a link in another thread that relates to an actual study carried out on behalf of NASA. It answers many of your questions. I'll see if I can find it.<br /><br />

 

[alpha_taur1]

Try here :<br /><br />http://www.isr.us/SEConcept.asp?m=2 <br />

 

[brand1130]

thanx, one last question though.<br /><br />How big would the base of this thing be? Any ideas?

 

[brand1130]

uppin...

 

[ehkzu]

The Andes at the equator are around five miles high. Ecuador. Might make a good base. Highest place on Earth at the equator.

 

[a lone wolf]

ok heres a question, what if the cable somehow detached from its anchor in space and came down to earth? Would it wrap around the planet or would it form a pile of sorts?

 

[heyo]

A few points.<br /><br />Don't get me wrong, I dig the idea.<br /><br />But, if the centrifugal force of the Earth's rotation keeps the elevator pulled tight, if it ever snaps or comes loose from it's foundation, guess what. Bye bye! You're on your way somewhere... where? depends on what time of day it happens.<br /><br />Also, the law of conservation of angular momentun would state that the elevator would make the day a teeny bit longer. Whether this would be measurable, I don't know. <br /><br />Also, as the transport vehicle climbed, it would have to gain the needed angular momentum it did not have as it got farther out and was making a larger and larger arc, this would tend to drag the nanotube elevator back to the west. How much? again, that would depend on the vehicle's mass, so I don't know.<br /><br />Heyo

 

[Saiph]

well, part would fly into space, and another part would try (the bottom section) but would basically come crashing down, and make a huge problem for anything east of it (i think east). <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[nexium]

I don't know how I missed this thread. Typically the ends will separate slowly when the ribbon breaks, so a quick responce team may be able to splice a few kilometers of ribbon into the gap. If not the ribbon will land gently in the ocean, if the break occurs less than 200? kilometers altitude. Neil

 

[rlb2]

Our team “The Skyclimbers” have sent a letter of intent and have been accepted to compete in the Climber competition. At this time there are 22 entries. The rule book for the ascent and descent of the climbers isn't finished yet. <br /><br />Most answers to your questions relating to this competition can be found at “The Spaceward Foundation” web site.<br /><br />Web Links:<br />Elevator:2010 Web Site: http://www.elevator2010.org<br /><br />This document.s URL: <br />Spaceward Foundation: http://www.spaceward.org<br /> <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[mcbethcg]

I thought the conventional wisdom today was that it would be anchored to a movable platform at sea, so that it could be moved as needed (rarely) to avoid space junk.

 

[nexium]

Hi mcbethcg: I agree; the other ideas are brain storming which have near zero chance for the first SE. <br /><br />Perhaps not so rarely; someone thought move the anchor ship daily to miss a peice of junk by 10 miles. I should think a one mile miss is sufficient, if we understand (and manage) the transients on the ribbon. Neil

 

[rlb2]

The climber and tether is in the test phase right now. As the competition heats up it will require moving up to greater heights. The next phase after 2006 may require it moving up a tether suspended from a hot air balloon.<br /><br />See the website above for the most accurate information on the Space Elevator competition; it is the official NASA Centennial Challenge website for the space elevator competition. I can’t say anymore about this so hopefully you get all your updates there.<br /> <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[mlorrey]

"Well, the big 'if' and always has been are the nanotubules. I see none. I see none being made of anywhere near the requisite strength (70-100 GPa's)or length, which is affordable. "<br /><br />As they are molecules, you can't see them... of course.<br /><br />This source (http://www.isr.us/Downloads/niac_pdf/chapter2.html) says: "The first paper appeared in Applied Physics Letters in April [Choi, 2000]. In this paper parallel, straight, clean nanotubes were grown on a nickel substrate. This in itself is not new, many researchers have now grown nanotubes by the same technique up to two millimeters long [Ren, 1998] and others have grown, with a different technique, roughly aligned nanotube ropes up to 3 cm long [Cheng, 1998]. However, Choi went a step further and characterized the growth. They clearly show an understanding of the process and demonstrate the capability to grow highquality, densely-packed, nanotubes. They discuss the dependence of the nanotube size (multi- or single-walled) and growth rate on the initial surface preparation.<br /><br />The second paper that is of interest appeared in Science in January [Yu, 2000a] with a follow-up of additional measurements appearing in Physical Review Letters in June [Yu, 2000b]. In these papers, Yu presents some of the first measured tensile strengths of nanotubes. Yu and colleagues appear to have done a thorough and well thought out experiment and got impressive results. Tensile strengths of 11 to 63 GPa were measured for individual nanotubes compared to Yu's references of theoretical tensile strengths of 300 GPa. (We used 130 GPa, Yakobson and Smalley, 1997, in all of our calculations.) The high measured tensile strength in one of the first such experiments is encouraging. <br /><br />In our pursuit of understanding all aspects of the space elevator system we have initiated a collaboration with one of the leading nanotube researchers. The collaboration is to entail growth of long, single-walled carbon nanotubes for impleme