One mile down, 61,999 to go

[tplank]

http://www.newscientistspace.com/article.ns?id=dn8725 <div class="Discussion_UserSignature"> <p>The Disenfranchised Curmudgeon</p><p>http://tonyplank.blogspot.com/ </p> </div>

 

[holmec]

nice, slowly but surely. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[tplank]

It is hard to not pull for the effort. To my non-engineer eyes, the hurdles look daunting, but there is a fundamental logic here that is fairly appealing to us unschooled. <div class="Discussion_UserSignature"> <p>The Disenfranchised Curmudgeon</p><p>http://tonyplank.blogspot.com/ </p> </div>

 

[jschaef5]

How easily would a space elevator be destroyed? Im thinking if a thunderstorm rolls by, the wind sheers can get pretty intense... <div class="Discussion_UserSignature"> </div>

 

[summoner]

Most platforms that have been proposed will be seabased and have the ability to move out of the way of storms. They will also be placed in areas that are relatively calm. <div class="Discussion_UserSignature"> <p> </p><p> </p><p> </p><p> <br /><table cellpadding="0" cellspacing="0" style="width:271px;background-color:#FFF;border:1pxsolid#999"><tr><td colspan="2"><div style="height:35px"><img src="http://banners.wunderground.com/weathersticker/htmlSticker1/language/www/US/MT/Three_Forks.gif" alt="" height="35" width="271" style="border:0px" /></div>

 

[jschaef5]

I assume they will also have giant no fly zones around them? Or atleast I would hope so. I first heard of the idea of space elevators right around 9/11 and since then I have feared that it would be a VERY easy target for hate groups. It's sad but this idea just seems so vulnerable to not just people like this but to mother nature as well. I assume the operating cost will be quite high after say 5 years. By then SpaceX will be able to get you there for cheaper <img src="/images/icons/smile.gif" /> (Hopefully)<br /><br /> <div class="Discussion_UserSignature"> </div>

 

[mlorrey]

Not at all. Space elevators will beat all launchers costs by a factor of 100. As for your concerns about terrorism, look at it this way: take a block of cheese, and a cheese slicer. Hold the slicer up in the air. Run the chese through the cheese slicer. Result: cheese is sliced, slicer is undamaged. <br /><br />A space elevator's carbon nanotube tether is like a cheese slicer.

 

[ltm_se]

And what or who is like the block of cheese? =)

 

[mlorrey]

an airliner. Better yet, an airliner is like an empty soda can, and the space elevator is like a gin-su knife.<br /><br />Back when I was in the USAF, when I was working on F-111D Aardvarks, one came back to base with damage from hitting power lines with a wing while flying in a terrain following mode (kinda like that guy who nailed the Italian ski lift a few years ago). The power lines had sliced half way through the wing, including one of the wing struts. <br /><br />Now, copper power lines are far more malleable and far lower strength than CNT, and were likely compromised by all the current going through them as well.<br /><br />Ever hear the term "clothselined"??? Saw a motorcycle accident once, guy was tossed off the bike, flew through the air, and lost his head, sliced off by a power line.

 

[jschaef5]

Haha that reminds me of this video of a cessna down in florida who got dominated by some powerlines...<br /><br />How thick are the nano tubes, not the actuall tubes like the actual cord that will run, the over all diameter. And I didn't know that it was that strong. Best of luck to them. <div class="Discussion_UserSignature"> </div>

 

[summoner]

One thing not to forget, is that any elevator that is built will have a shoot to kill zone around it both in the water and in the air. Any plane or ship that enters the protected zone will be destoyed first with questions coming later. <div class="Discussion_UserSignature"> <p> </p><p> </p><p> </p><p> <br /><table cellpadding="0" cellspacing="0" style="width:271px;background-color:#FFF;border:1pxsolid#999"><tr><td colspan="2"><div style="height:35px"><img src="http://banners.wunderground.com/weathersticker/htmlSticker1/language/www/US/MT/Three_Forks.gif" alt="" height="35" width="271" style="border:0px" /></div>

 

[vogon13]

Many threats to a space elevator.<br /><br />Lightning<br /><br />Meteors <br /><br />Orbiting space debris<br /><br />Cosmic rays (on the high end)<br /><br />Radiation (Van Allen belts)<br /><br />Carbon 14 being incorporated into the CNT (short halflife causes CNT to break when C14 decays to nitrogen)<br /><br />Atomic oxygen at higher altitudes<br /><br />Ozone?<br /><br />CME on the high end? (I just thought of that, might not be a problem)<br /><br />Luddites and terrorists.<br /><br />Congress killing the program 1/2 way through.<br /><br />(there are probably 100 more . . . .)<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[spacester]

Oh, so that's why you vogons never adopted space elevators?<br /><br />Of course, plausible ways of dealing with all those real problems have been advanced, some more plausible than others. After going thru the Edwards proposal, IMO the biggest problem of the lot - after the unobtainium thing of course - is the atomic oxygen degradation.<br /><br />One of the coolest things about the space elevator is the ease with which some of the problems are dealt with. Of course, it's the last problem that matters most, whichever that turns out to be.<br /> <div class="Discussion_UserSignature"> </div>

 

[mlorrey]

The oxygen problem is why I prefer anchoring it just above the atmosphere with a big hanging platform, like an aircraft carrier deck in space. Suborbtial craft can just boost straight up, land on the deck, drop off and pick up cargo and passengers, then fly off the edge and drop back down to the surface. This would certainly cut the expense to that point to about 1/10th the current low end cost to LEO.

 

[nyarlathotep]

>>"I assume they will also have giant no fly zones around them? Or atleast I would hope so. I first heard of the idea of space elevators right around 9/11 and since then I have feared that it would be a VERY easy target for hate groups."<br /><br />Given the costs involved, the consortium building the elevator would likely hire a CVBG or two for defence. They'd very likely also use electric power generated by the carrier for powering climbers.

 

[spacester]

Wow, that's a new idea to me. I'm trying to picture it, trying to see if there's a problem with the orbital mechanics for starters. You still have a gravity gradient so the line stays taut, you're still above the equator . . . you still can put your center of mass at GEO altitude . . .<br /><br />Wait a minute, what is the configuration here? No cable from ground to platform, and cable from platform up to beyond GEO?<br /><br />How do you maneuver this thing to avoid the inevitable obstacles? An ocean terminus lets you deal with that problem in the classic Edwards design. <div class="Discussion_UserSignature"> </div>

 

[cuddlyrocket]

What I like about this is that they're designing a 1 or 2 mile tether for which they see a market. If they're right, further development can be supported by profits, and the length etc can be developed in stages. Eventually, there'll be enough knowledge and experience to give people confidence about building a space elevator.

 

[no_way]

the longest journey begins with one step ..<br /><br />but i see a plenty of frequently asked questions about space elevators all over again, could we perhaps have a page which links to FAQ and reference sites on certain oft-discussed topics? <br /><br />like http://www.liftport.com/faq.php for instance<br /><br />space.com wiki, anyone ?

 

[pmn1]

<font color="yellow">an airliner. Better yet, an airliner is like an empty soda can, and the space elevator is like a gin-su knife. </font><br /><br />What if the airliner is also made of carbon nanotubes - i cant see it not being used anywhere where strength and lightness are needed. <div class="Discussion_UserSignature"> </div>

 

[tomnackid]

What if the airliner is also made of carbon nanotubes - i cant see it not being used anywhere where strength and lightness are needed.<br />--------------------------------------------------------------------------------------<br />Then the manufacturers will only use enough carbon nanotubles to equal the strength of an aluminum plane (more or less) but with a weight many many time less. All things being equal, airliners won't really benefit much from being STRONGER than they are now, but they will benefit greatly from being much LIGHTER than they are now. Although carbon fiber planes WILL be less susceptible to the metal fatigue problems that plague aluminum aircraft.

 

[nacnud]

There is a problem with a tether that doesn't reach the surface, you can't use the Earth roatation to reboost the tether after each use. You'd have to use some form of propultion to keep the tether up.

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>Ever hear the term "clothselined"??? Saw a motorcycle accident once, guy was tossed off the bike, flew through the air, and lost his head, sliced off by a power line.<p><hr /></p></p></blockquote><br /><br />My grandpa can tell you all about that. He was in the signal corps for a while in WWII. Drove Jeeps around Europe to deliver messages. The Nazis had taken to stringing piano wire across the road at just the right height to reach the neck of a person riding in a Jeep with the top off. The Allies quickly got wise to this. My grandpa's Jeep had a tall blade on the front to slice the piano wire before it could slice his neck. (If you've ever seen a Jeep in a museum and wondered why it had that absurdly tall hood ornament, that's why.) He had one close call -- the Nazis had apparently tried using some very heavy-gauge wire, and they saw that blade bend waaaaay back. They weren't going very fast at the time, fortunately, so they were able to duck. The wire passed over their heads and made a loud twang. They parked, went back and cut it, then continued on their mission.<br /><br />He can also tell you about roadside bombs, alas. More specifically, landmines. They drove over one. Killed his partner instantly. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[daniko]

When talking of mid-versions of the elevator that could "pay" for the final development, here is something that comes to me:<br /><br />Let pick several things that are mostly reallity in our days:<br />- "SeaLaunch" corporation lauches rockets from sea platform<br />- "AirLaunch" is on it's way - the plans are to use Russian MIG's to launch missiles from high altitudes. Payloads are estimated to 200 kg.<br />- "LiftPort" tests are with HALE platform kept aloft with baloons<br /><br />If "LiftPort" succeed in making a HALE platform that goes above the dense atmosphere layer than:<br />- A lift robot could lift rockets to the top<br />- That robot could produce fully automated launch operations. (that is how SeaLaunch platform operates)<br />- That kind of launches has better payload to overall mass ratio (less fuel, less fuel containers, no air protections)<br />- On that heights the aid of the Earth's rotation is bigger than on the ground<br /><br />May be such configuration could launch payloads about 500 to 1000 kg.