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#1 2005-03-04 14:07:45

flashgordon
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Registered: 2003-01-21
Posts: 314

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

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#2 2005-03-05 02:15:57

Rxke
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From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Looks promising. let's hope it's not just another attention-seeking stunt for grants...

Big promise, though, so they will have at least  *something* up their sleeve. Restarting growth, hmmmm... Even if it doesn't produce 100% flawless tubes, this could be good news.

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#3 2005-03-05 05:48:50

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Even if this cant be used for space elevators its use in other materials for space would prove a great boon. Imagine lighter tougher space suits, lighter space craft and rockets. The possibilities are endless........ big_smile


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#4 2005-03-07 18:45:04

reddragon
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Even if this cant be used for space elevators its use in other materials for space would prove a great boon. Imagine lighter tougher space suits, lighter space craft and rockets. The possibilities are endless........

Definitely. And space applications are just the beginning. I won't be surprised if in another decade or two carbon nanotubes find a use in almost every industry. They may be to the 21st century what iron was to the 19th or plastics to the 20th.

I'm also surprised the military hasn't started working on nanotube technology. They'd probably beat kevlar for body armor. But then the military has a poor record on body armor.

Of course the space elevator is what I care about the most. I for one believe it can be built and will open space to humanity.


Far out in the uncharted backwaters of the unfashionable end of the Western Spiral arm of the Galaxy lies a small unregarded yellow sun.

             -The Hitchhiker's Guide to the Galaxy
              by Douglas Adams

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#5 2005-04-13 02:09:07

John_Frazer
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From: Boulder, Co. USA
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

I'm importing more on this topic from another topic that digressed into space elevators
>Human missions
http://www.newmars.com/forums/viewtopic … 708]>>Crew Vehicles Discussion (pages 6-7)

GCNRevenger April 12 2005
> Are you out of your mind? The Skyhook kooks are insane, somehow just barely latching on to the speeding tether in the breif seconds the supersonic vehicle would have to slip within those razor-thin centimeter tollerances, moving well above the speed of sound, in the middle of the sky... The rendevous alone would be almost as hard as the ballistic missile shield being built.

As I said, look at the techniques used for landing a naval aircraft on a warship -in up to sea-state 4, at night, while there's a battle going on, when losing a plane or ship or even just an opportunity to land this particular aircraft before it runs out of fuel or loses a chance to pounce on a submarine means losing an encounter, a battle, a war, and a nation. (see the Argentinian experience with not being able to get enough wind over the bow to launch their carrier-borne Skyhawks to engage the British Carrier, a few hundred miles away while the few land-based planes which could reach it were passing overhead at the same time on their way with some of their few precious sea-skimming missiles.)

Whether it's a rotovator or hypersonic skyhook, the plane reels out a cable with a hook, and the landing area spreads a net or lattice of cables to catch it. In addition to the time given them by their close approach, they gain time by extending and maneuvering the cables/hooks to snag.
Forward said that they can extend the rendesvous time from 20-30 seconds of close approach to over 2 minutes.
At their altitude, there's no such thing as airspeed (no air...), so any aerodynamics simply don't apply to the docking/landing.

Velocities needed for getting a load to orbit is reduced by nearly half for the launch vehicles, and re-entry is only a few km/sec -about what the SpaceshipOne was designed for. Any of the X-prize contenders show the way. (and they're about as far from the vehicles in question as an F-18E is from the aeroplanes which first raced across the English channel, so yes, they're only very vaguely an indicator of what's needed.)
As it's widely seen, applying tensile structures to attaining orbit is getting the best of both worlds. Neither part of the trip up/down is required to operate in the opposite extreme environment: the vehicle doesn't need to get up to orbital velocities, and the tether doesn't need to operate in atmosphere where large fast structures have problems with split-second timing and centimeter precise maneuvering. Requirements to meet the extreme conditions are relaxed on both parts, and both parts use their unique strengths to best suit the conditions where they operate.

In any case, I was just reporting it here -it seems to be news. Others with better qualifications than any of us here have published articles in peer-reviewed scientific and engineering journals -and not gotten laughed out.
Detractors are invited to submit articles to the AIAA, AAS, NASA, and other such publications.
Tabloids and popular technology publications and lay-person internet message boards just don't matter to real engineers and scientists who are qualified to judge a proposal.

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#6 2005-04-13 05:51:33

Fledi
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From: in my own little world (no,
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Posts: 325

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Due to the nature of the rocket equation 1/2 of orbital speed would mean 10 times the payload mass than to orbit, a much easier to handle margin for weight optimization of the space plane, which would face a lot less reentry problems (the figure for payload mass is also a good guide here).
As it has already been posted for several times docking tolerances are way beyond centimeters scale, too.
The tip speeds of up to 4 km/sec can be achieved with todays materials and I'm talking about quite cheap ones there.
And as to how safe cables under constant strain are look at any suspension bridge.

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#7 2005-04-26 10:09:12

SpaceNut
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From: New Hampshire
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Posts: 28,832

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

More on prizes to entice business into the space frontier.
[url=http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2005/04/25/MNGM4CEAPG1.DTL] NASA offers prize for 'space elevator'
Beams of light could propel cargo, humans[/url]

Sort of interesting the concept of powering the elevator by laser beams.

NASA has $400,000 in prize money riding on a competition to stimulate the innovative concept -- no matter how weird it may seem -- for sending people, spacecraft and robots directly out to Mars and the other planets of the solar system.

The space agency is serious, and the modest money is helping to allay the concerns of the Israeli-born Shelefs, whose nonprofit Spaceward Foundation in Mountain View has been named to manage NASA's first-ever competition open to professional and amateur space fanatics alike.

And then there is the chance for more money as well as more items to research for the vision.

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#8 2005-04-27 07:46:52

SpaceNut
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

LiftPort Group, the Space Elevator Companies, to Open Its First Carbon Nanotube Manufacturing Facility

LiftPort Nanotech will make and sell carbon nanotubes to glass, plastic and metal companies, which will in turn synthesize them into other stronger, lighter materials (also known as composites) for use in their applications. Already being used by industries such as automotive and aerospace manufacturing, carbon nanotube composites are lighter than fiberglass and have the potential to be up to 100 times stronger than steel.

We see the development of carbon nanotubes as critical to the building of the space elevator," said Laine. "Opening a commercial production facility enables us to generate revenues in the shorter term by meeting the growing market need for this material. At the same time, it enables us to conduct research and development in this arena for our longer term goal of a commercial space elevator.

For those needing to catch up:

A revolutionary way to send cargo into space, the space elevator (as proposed by LiftPort) will consist of a carbon nanotube composite ribbon stretching some 62,000 miles from earth to space. The elevator will be anchored to an offshore sea platform near the equator in the Pacific Ocean, and to a small counterweight in space. Mechanical lifters will move up and down the ribbon, carrying such items as satellites and solar power systems into space. More information can be obtained at the company's web site at Liftport.

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#9 2005-04-27 09:14:07

SpaceNut
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Thou not of carbon nanotubes for a space elevator they are unique in that they can be used for other things.

[url=http://www.chron.com/cs/CDA/ssistory.mpl/space/3155509] 'A small step' in Mars' direction
NASA teams up with Rice to build nanotube cables for lighter crafts[/url]

THE PROJECT
• What: Rice University gets $11 million from NASA and Johnson Space Center gets $4 million
• Why: To develop lightweight, more efficient power cables for future spacecraft
• Beyond NASA: Research could lead to entirely new power transmission grid on Earth

No need for superconductivity, if this works:

NASA has asked Rice to build power cables out of carbon nanotubes, a hotdog-shaped cylinder of carbon atoms with special properties. So special, in fact, that Rice scientists plan to build nanotube cables that can conduct electricity as much as 10 times better than copper at about one-sixth the weight.

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#10 2005-04-27 15:54:38

Fledi
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From: in my own little world (no,
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Posts: 325

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

They are obviously confident that they can produce nanotubes for the price of copper. Artificial diamond production did not reach that barrier yet as far as I know. But it would be tremendeous if they could make that happen.

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#11 2005-04-27 19:21:00

Martian Republic
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From: Haltom City- Dallas/Fort Worth
Registered: 2004-06-13
Posts: 855

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

They are obviously confident that they can produce nanotubes for the price of copper. Artificial diamond production did not reach that barrier yet as far as I know. But it would be tremendeous if they could make that happen.

I doubt that they will be able to make it cheaper than copper wire. But, the main saving will come in weight reduction of the rocket rather than having cheaper wire. Well, they said that 25% of the rocket weight is made of copper  wire and if they can make it they will have 1/6 the weight of carbon fibers, then that would be a great weight saving strategy.

Just for an example let say we have a 200,000 pound capsule. They said one quarter of the weight comes from come from copper or copper wiring. OK, that 50,000 pounds copper or copper wiring. Now 1/6 of 50,000 is  about 8,000 of copper or carbon wire to replace that copper wire or a saving of about 42,000 pound from a 200,000 pound capsule or capsule that only weighs 158,000 pounds. If that is true, then that a great weight saving strategy so they can build a smaller rocket or build a bigger rocket by about 20% and do by using lighter materials then we have in the past.

I think that the reason that there interested in that carbon wire. If they could do that and be able to knock the weight off in other areas of the space craft too, along with increasing the thrust of these new space ship, it may become feasible to eventually build one piece shuttle in the not to distant future.

Larry,

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#12 2005-04-28 03:18:50

Shaun Barrett
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From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Martian Republic:-

I doubt that they will be able to make it cheaper than copper wire.

    Hmmm.
    As I've often emphasized, I don't classify myself as any kind of expert on geology or physical geography, but I wonder whether carbon might have an intrinsic advantage over copper when it comes to affordability.
    Copper has to be mined - dug out of the ground - usually in compound form, I presume, and then isolated. Native copper exists, I'm sure, but it must be in relatively small quantities by now, no?
    Carbon, on the other hand, is still readily available in either solid (coal), liquid (petroleum) or gaseous (methane) form, and likely to remain so for much linger than copper. We could even harvest it from the CO2 in the air, I guess, if the need arose. (Maybe killing two birds with one stone, to some extent, vis-a-vis 'global warming'.) But it's easier to get the carbon out of fossil fuels, I imagine(?).
    While copper must become progressively more difficult to recover from Earth's crust, as all the superficial deposits become 'worked out', the carbon in coal and natural gas will provide an ample supply of carbon for centuries to come.

    Again, reiterating my comparative ignorance on the subject, it looks likely that carbon-based power cables must ultimately win out over copper cables as far as economics is concerned.
    I believe the processing of carbon into nanotubes will become straightforward as technology quickly advances. So, I don't factor in current difficulties in that regard because I feel sure we will overcome them.

    I'm willing to be proven wrong on any of this, by the way.  smile

    In any event, if it costs you twice as much for the carbon-nanotube cable in your spacecraft, but you get many more kilograms of payload into LEO for fewer dollars, who cares?


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#13 2005-04-28 04:58:43

SpaceNut
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From: New Hampshire
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Posts: 28,832

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

But the problem with making wire out of carbon is that it will not deliver the energy put in at one end to the destination end of the conductor.
Resistors are made from carbon and as the name implies it disapate energy into heat across the device. Also the amount of resistance does lower with cooler temperatures, while it will rise as it gets hot.
So unless the nanotube carbon has a low resistive property it will only be part of this new wires design.

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#14 2005-05-05 03:35:30

Visionary Explorer
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Posts: 31

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

For all the space elevator buffs out there, a PowerPoint presentation by Brad  Edwards (via SER/SpaceRef):

http://www.spaceelevator.com/docs/Gener … tation.ppt

I haven't had time to look at it yet, but I'm sure it's unique if not interesting.

And if you don't have PowerPoint, you can use the PowerPoint Viewer from Microsquish (err, Microsoft):

http://www.microsoft.com/downloads/Than … ...Lang=en

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#15 2006-08-27 23:52:26

noosfractal
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From: Biosphere 1
Registered: 2005-10-04
Posts: 824
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

The ultrastrong, lightweight carbon-nanotube fiber, branded SuperThread(tm) by the company, can have better properties than steel for many applications and could soon be the primary substance from which airplanes, automobile parts, and sports equipment are made. Initial tests show that SuperThread is pound for pound (for the same weight) one-hundred times stronger than steel and less than one-fortieth the weight.

http://www.lanl.gov/news/index.php?fuse … ry_id=8855

8)


Fan of [url=http://www.red-oasis.com/]Red Oasis[/url]

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#16 2006-09-20 10:08:28

GCNRevenger
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Finally! A commercial application! It took long enough...

...however, its still not single-walled nanotubes, the stuff elevator cable would have to be made from most likely.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#17 2006-09-27 22:33:37

flashgordon
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

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#18 2006-09-27 23:46:33

Rxke
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From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

:?  :?  :? Pachebel ballet on PBS??? You sure that was the link you wanted to supply?  lol


EDIT: Disregard comment: link fixed...

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#19 2006-09-28 20:11:18

flashgordon
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Registered: 2003-01-21
Posts: 314

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

hmm . . . very interesting . . . i'll try to find the correct link; i have no idea how the url could be that far off;

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#20 2006-10-23 09:17:27

SpaceNut
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

From Xcup, looks like a winner to me..
Robot climber comes oh-so-close to prize; Judges say team just misses $150,000 in Space Elevator Games
Not sure of the cable type...

Tether tug of war
Saturday night's Tether Challenge, in which ultra-strong strands of material were put to the test in a mechanical "tug of war" machine, also sometimes tested the competitors' patience. Three of the four teams were disqualified when their tethers measured just under 2 meters (6.5 feet), the minimum specified in the rules.

One of the disqualified team members complained to the organizers that "you have effectively screwed over the whole goal of this competition."

After the unofficial matchups, California-based Team Astroaraneae the only team that was qualified for actual competition went up against a reference "house tether" that was 50 percent heftier by weight. At the end of a nail-biting stretch-off, the Astroaraneae tether broke at 1,335 pounds of tension while the house tether held firm. That outcome ruled out any payoff in the Tether Challenge this year.

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#21 2006-10-23 19:54:26

SpaceNut
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

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#22 2006-10-27 11:46:30

publiusr
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From: Alabama
Registered: 2005-02-24
Posts: 682

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

http://www.nanotech-now.com/news.cgi?story_id=08268
The link should work now.

Space elevator--a good payload for Direct
http://www.lulu.com/content/440980

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#23 2007-04-25 16:49:51

noosfractal
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From: Biosphere 1
Registered: 2005-10-04
Posts: 824
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Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Researchers Shatter World Records with Length of Latest Carbon Nanotube Arrays
http://www.physorg.com/news96733560.html

carb_nanot_stack.jpg

18mm

Hey, that's not too bad for 2007.


Fan of [url=http://www.red-oasis.com/]Red Oasis[/url]

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#24 2007-04-25 17:09:39

noosfractal
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From: Biosphere 1
Registered: 2005-10-04
Posts: 824
Website

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

The ultrastrong, lightweight carbon-nanotube fiber, branded SuperThread(tm) by the company, can have better properties than steel for many applications and could soon be the primary substance from which airplanes, automobile parts, and sports equipment are made. Initial tests show that SuperThread is pound for pound (for the same weight) one-hundred times stronger than steel and less than one-fortieth the weight.

http://www.lanl.gov/news/index.php?fuse … ry_id=8855

8)

These guys have a web page now

http://www.cnt-tech.com/

but their contact address seems to be somebody's house.  Are they going to pretend to be a garage startup?


Fan of [url=http://www.red-oasis.com/]Red Oasis[/url]

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#25 2007-06-23 12:15:24

publiusr
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From: Alabama
Registered: 2005-02-24
Posts: 682

Re: Space Elevators, Ho! - carbon nanotube growth breakthrough!

Boron buckyballs might be wiser...

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