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The idea of a space elevator has been around since the late 1800’s, but despite big dreams and years of research, the low-cost, easy access to orbit that a space elevator promises is likely still decades away. The biggest problem rests on the fact that no one has been able to successfully manufacture long ribbons made of ultra-light, ultra-strong carbon nanotubes, the only known material that is strong enough for a space elevator. But entrepreneur Michael Laine believes a lunar elevator – a space elevator from the surface of the Moon – could be created with materials that are available now. With more research and the right amount of capital, Laine says a lunar elevator could be built within a decade.
While Laine said he is still “emotionally very invested” in the concept of a space elevator based on Earth, for now he has shifted his focus to the lunar elevator. “There was a question of where was I going to put my time,” he told Universe Today, “and being able to do this soon – perhaps within 5-7 years and not some mythic 15-25 years in the future is enticing.”
Since the Moon’s gravity is only one sixth that of Earth, it drastically reduces the requirements of the ribbon. A material that is available now, a synthetic polymer material called Zylon (poly(p-phenylene-2,6-benzobisoxazole) which has high strength and excellent thermal stability, could be used.
Additionally, the components to build the elevator that would be sent to the Moon would be relatively lightweight, so a smaller rocket would do the job. “The physical requirements of the system look like you could use a standard Atlas or Delta rocket to launch the components.” Laine said. “That’s a big deal that you don’t need to build something like a Saturn V.”
While Laine said he believes a lunar elevator in 5-7 years is feasible, he didn’t want to go on record as saying it could be built in such a short time frame without adding some major caveats.
The biggest hurdle could be getting access to the 6 cubic meters of the Zylon material. “That actually could be the biggest challenge,” Laine said.
Additionally, there are still an untold amount of unknowns about building such a system. “I used to say for the space elevator that we still didn’t know all the questions, let alone the answers,” Laine said, “and that is even more true for the lunar elevator.”
The other hurdle is money. But a lunar elevator might actually be cheaper to build, initially, than a space elevator from Earth.
An Earth-based elevator is essentially a long cable – perhaps 100,000km (62,000 miles) long — that is anchored on Earth at one end with a counterweight at the other end (a large satellite, for example) in (beyond) geosynchronous orbit. Gravity and centripetal acceleration keeps the cable, or ribbon rigid and a small elevator, or “Lifter,” can move up the elevator at a fraction of the energy and financial expenditure of launching an object into orbit. Once the elevator is built, using the elevator to put things in orbit could cost hundreds of dollars per pound, versus the $7,000 per pound it takes to launch satellites with the space shuttle.
A lunar elevator would use a ribbon at least 50,000 kilometers (31,000 miles) long extending through the Earth-Moon L1 LaGrange point from an anchor point near the center of the visible part of Earth’s moon. A smaller Atlas or Delta rocket could send the components the L1 point, and the Zylong ribbon would be spooled from that point towards the Moon and the Earth.
“You would use the Atlas hardware as part of your counter weight,” said Laine. “But that’s a very small counterweight, which means that your cargo that you are taking up and down from the Moon is going to be small. This is not like the Earth elevator where you were going to be putting 100 tons a week into space. This is a very small system, capable of transporting 200-250 kilos.”
But to put that in perspective, Laine said, the entire sample return system for the Japanese Hayabusa probe that recently returned from an asteroid was only about 20 kilos.
And that’s what Laine has in mind for the first lunar elevator: a sample return mission. “It would be a lunar sample return mission within the next 5-7 years, for what we think is a pretty reasonable price,” he said.
Once the initial ribbon is up and running, Laine said you could send up more ribbon to strengthen it, using same concepts for the Earth elevator, such as multiple stages of construction and ribbons that are added to it.
Of course, none of this – including the money – is trivial. Although the first string might be less expensive than an Earth elevator, additional construction of the lunar elevator would be fairly expensive, and take more time compared to the Earth elevator. “Once the first string on the Earth elevator is built, you work from the bottom and go up, whereas on the lunar elevator you’ll have to send it from Earth. So that part starts adding up in a hurry,” Laine said. “We don’t have a complete estimate on price yet but an Atlas or Delta, that is a known and reasonable price tag. We’re not talking about billions and billions of dollars here — maybe hundreds of millions — but not billions.”
Still, he has a vision and a plan.
“It is not a flag and footprints vision of going to the Moon,” Laine said, “but it goes to the heart of the new NASA budget and focus of developing technologies and infrastructure so that things can happen. And that’s what we hope we can do by developing this ribbon. And then we jumpstart the process of creating an outpost or a research lab. We’ve played with the idea of using the counterweight at the end and using a habitat, something like a Bigelow (Laine stressed he hasn’t talked with the Bigelow people yet about this) and if we could tie a couple of modules together they would make a great counterweight and that puts you in an interesting position. Some people don’t think going to the Moon is worthwhile if you are going to Mars, but a lot of people think a fuel depot makes sense. We could be a great fuel depot for some of those long duration missions because we want that extra mass. In the Earth elevator, the counterweight is basically dead mass. For the lunar elevator, it becomes a working environment. So some people go to the modules, some people go to the Moon, some people go to Mars using this as a refueling and construction station. Once it is up and running you have safe reliable access to the moon, for the price of a Delta or an Atlas. That’s huge.”
But Laine said he doesn’t want to give anyone the impression that he and others interested in this concept have everything figured out. “We’ve studied this enough to know that it is feasible and interesting and likely to happen sooner rather than later, which is why we’re tackling it.”
So, Laine and a core group of space elevator enthusiasts are starting a series of workshops to discuss this concept and tackle some of the significant questions with anyone who is interested and who might have the brainpower and spirit to understand and undertake such a project.
The first workshop is July 29-August 1 in Seattle Washington. See this link for more information
“I’m a big believer in connecting with community, so if artists and musicians, want to come, that’s great,” Laine said. “Engineers, science guys, rocket guys would be helpful. But politicians and marketing people are equally important to answer the big questions of where we should focus our time and efforts.”
There is also a space elevator conference August 13-15 at the Microsoft Conference Center in Redmond, Washington. Find more details at this link.
Laine started a space elevator company in 2003, LiftPort, which fell to financial problems in 2007. He sees the lunar elevator as a possible rebirth for the company, which once had 14 full-time employees. “This is a renaissance project, a rising again,” he said. “I’m applying a lot of what I learned on the Earth elevator to this new vision. While tackling the Earth elevator, all my money came from real estate, and I had plenty of money for my needs. But this time is different. For us to build this thing we are going to have to earn our way.”
“But I think it could be phenomenally lucrative, too,” Laine continued. “We are going to make discoveries along the way that will lead to products and services that are not related to going to the Moon. We think there is a solid value proposition as part of this.”
Neat looking,but all the things that fly inbetween the moon an earth like miniture metoroids,solar winds,etc,etc…the ribbin would need a repair team…How much to launch just the counter weights alone? Seem better to just design new braking systems to get to the moon. Any earth base elevator would need a space junk force field
“The biggest hurdle could be getting access to the 6 cubic meters of the Zylon material.”
Is this a misquote? 6 cubic meters of Zylon material doesn’t sound like nearly enough…?
@HelloBozos – Good point, micro meteoroids, CME’s, Space Junk… one good hit, and the fat lady sings? (Definitely a politically incorrect statement ~@; )
Aqua:
They’re talking about a very, very thin ribbon, stretching out over only 50,000 kilometres. The circulatory system of a ~150 pound human is about 100,000 kilometres long. Very thin, but very long;). And what’s a 150 pound human… maybe 1 cubic metre, 1.5 tops? And a lot of our volume isn’t part of our circulatory system.
So I can see 6 cubic metres being plenty. Keep in mind that 6 cubic metres of Zylon is 9.36 tonnes. That’s a fair amount of mass for such a thin, (comparatively) short cable.
In fact, 6 cubic meters of Zylon would (in this application) have a(n average) diameter of 390 microns (0.39 mm).
Zylon has been used since 2001 in F1 to tether the wheels to the chassis, and as of 2007 the cockpit must be clad in Zylon anti penetration panels. The Indy Racing league did the same thing in 2008.
Zylon has a Youngs Modulus of 270 GPa, compared to 200 GPa for steel, 287 for Beryllium and 329 for Molybdenum.
I have always found it interesting that people argue for a lunar base as a fuel depot for martian or interplanetary missions. However, it makes little sense to go down into a gravity well using energy and then lifting back up out of it using energy for this purpose.
I think one clear problem with this is that the zylon would be subjected to hard UV. These types of organic compouds photo-degrade. The thin cable might quickly disintegrate. Also, if the return to the moon program is cancelled it is questionable what this system is meant to accomplish.
LC
Getting to the Moon, Mars and beyond.
However until there’s a solid reason (in investor’s minds, anyway) to get to the moon in the first place, it’s all going to remain in the idea phase.
@Lawrence B. Crowell:
PowerLite Pro-Rigging (I won’t link to the website, least people think I’m advertsing for them) sell Yacht rigging, which essentially consists of a PBO (zylon) core for strength and rigidity which is overlain by a ‘protective extrusion’, to protect it from UV Degradation, cuts, abrasion and moisture.
I see no reason why a similar setup couldn’t be used here – in fact PBO can even be metallized.
Surely proper utilization of the free-return path, famously used in the saving of Apollo 13, undercuts the need for a Luna elevator?
Last illustration is interesting, while a space elevator is constructed with the anchor on the equator I’ve often wondered if it was possible to relocate it afterward.
@TerryG :
The free-return trajectory can only be utilized if you have no intention of orbiting or landing on the moon (Apollo 13 did neither, hence it had no need to use fuel to brake, and then accelerate again for the return trip).
I so don’t get it…
An Earth-Lunar trip has three parts – Launch, coast, and Land.
You take the most difficult part (launch), and ignore it.
You then take the easiest part (coast) and complicate it – you now need to dock with a non-orbital target (so you cannot do it slowly and carefully – have to nail it fast)
You then take the last part (landing), which was relatively easy to begin with, and maybe make it easier, except you can only go to where the elevator is attached.
If we’re going to attempt something as complex as an Elevator, it needs to provide very high value. An Earth Elevator solves the launch problem, so is a worthwhile goal. A Mars Elevator has value too. But this specific project is a waste of time, methinks.
Kevin, CEB, I agree, there seems to be little or no ROI in this.
If, and this is a big if, it makes sense to make fuel on the Moon, perhaps Heinlein solved the practical problem long ago: a mass launcher. Then you can dock at conveniently placed fuel depots at will.
It takes more energy to do (and perhaps some of that fuel for Moon or Earth or Lagrange orbit insertion) but solar energy is free.
The real deal would be if an Earth atmosphere scoop or skimmer could scoop up more water (or H+O) for fuel than it burns. I have no idea, but it could be initially cheaper if it works.
There may be no good reason to go to the Moon except tourism and science, most resources is closer at hand (Earth, NEOs) than below that particular gravity well.
Torbjorn Larsson OM: Solar energy is *not* free. Every watt has to have significant infrastructure behind it. That infrastructure degrades over time and needs to be replaced in a regular basis. Replacing PV panels and storage systems on the moon would be *very* expensive. Far more expensive than refuelling an underground fission generating station that might well last for hundreds of years instead of the ~10-15 lifetime-before-complete-replacement for solar panels.
Why do people keep insisting that “solar is free”?
Obviously this is a technogy which isn’t going to be feasible unless we find something on the Moon which can be used on Earth in great quantity.
This means there are about 5 or 6 projects which will preceed this before it will be possible. I.e. Man missions to Moon, Missions to excavate caves etc for bases, building the initial bases & industry, etc.
So there is plenty of time yet, to keep researching better materials and propulsion systems. Personally, I see solar power magnets as the best method… but who knows what will be found in 15-30 years.
solar is not free. but until fusion is figured out, solar is relatively cheap and scales down well.
What does all of that have to do with the Lunar SE though? Even if there are diamonds, He3, and free nachos on the moon, it is still a pretty contrived way of getting from here to there.
I don’ see a point in this. Just because it’s in space doesn’t mean it will be easier to navigate to it. Compared to the Moon, it will be tiny, and if there is significant traffic at the dock, then that increases the chances of collisions.
Also, the elevator will be attached to one location on the surface, which doesn’t help you if you need to get stuff to a locations many kilometers away.
Plus, does the moon rotate fast enought to allow an elevator in geosynch orbit?
@ gopher65:
In my case it is so, because I meant it is freely available. The Moon doesn’t have much oxidizable or reducible volatiles, so that is out. The same scarcity goes for radioactive minerals, I believe.
That people should believe or claim solar energy is zero cost sounds contrived. Why would they claim that?
“In my case it is so, because I meant it is freely available.”
Solar power is freely available in exactly the same sense uranium is freely available. It’s gratis if you only expend the resources to gather it and use it.
“The Moon doesn’t have much oxidizable or reducible volatiles, so that is out. The same scarcity goes for radioactive minerals, I believe.”
There’s a scarcity of photovoltaics on the lunar surface I believe; so you’ll have to bring those with you.
They have a certain mass and over their lifetime they will produce a certain amount of energy with a certain time-varying power profile.
This is exactly analogous to bringing a small reactor with some 20% enriched fuel with you.
I agree with CrazyEddieBlogger.
Earth or Mars would be worth while but the moons gravity well is so small as not to justify a moon elevator. Besides you can probably launch from the moon using a type of rail gun launcher.
This story has now appeared in Russian, so the race is on — see here:
http://www.rian.ru/science/20100720/256671625.html
This is a great concept but perhaps even in the lunar version “a space bridge too far”. I’ve always been partial to the concept of ‘rotating lunar skyhook’, that could be demonstrated with SMALL payloads on single-launch missions, first in LEO and then LLO.
See an excerpt (and links) from my recent story:
http://www.msnbc.msn.com/id/32767421/ns/technology_and_science-space/
“What really intrigues me is that the moon is the perfect place to test out a revolutionary space transportation system — the “skyhook” or space elevator system. The concept has been around for a century: Essentially, just lower a rope from space to the ground, and use that to pull your payload into orbit.
“Making the concept a reality in Earth orbit would be far beyond any credible near-term human capability. Not so at the moon. Its lower gravity and lack of atmosphere provide the perfect setting (and the perfect rationale) for a skyhook system that slowly spins as it orbits the moon, dipping its end near or onto the surface every two hours. The tether would have to be heavy, but it is well within the range of plausible space technology.
“A “practical” concept for a lunar space elevator was described in Omni magazine by Bob Forward and Hans Moravec in 1981 [link]. Moravec expanded upon the idea in 1986 [link], saying the skyhook system would offer “a fine alternative to rockets for getting supplies and personnel to and from the lunar surface.”
“Such a system could be tested on a small scale at first, and then ramped up incrementally. That’s the beauty of this Flexible Path approach: Each step in capabilities leads to the next step within reasonable reach. Giant leaps into the unknown are not called for. Decades-long projects aren’t needed. Each new goal is well within the office term of the president who endorses it.”
Some of the commenters here need to go back and re-read the article. Wait for human exploration to find something valuable before building it? That’s at least two orders of magnitude more expensive than this project. Meanwhile a lunar elevator and supporting infrastructure could reduce the cost of lunar exploration significantly. A lunar mass driver presents an even bigger difference in cost. This project would launch on a single Atlas or Delta rocket. We launch roughly a half dozen of those per year. Finally, yes, launch to Earth orbit and re-entry are two of the most difficult parts of space travel. However, the complexity of launching from the surface of a hostile planet should not be minimized. The Apollo missions took everything they needed with them, including a launching pad, just to get a 250 kg payload back to the Earth. It took a Saturn V rocket to do that, and we can’t build those anymore.
For a proof of concept elevator. The moon would be very good. If something goes wrong then no one gets harmed.
Hi ya’ll.
Thank you for your thoughtful feedback. I will try to respond to your questions, comments and concerns.
Before I do that, I want to stress what Nancy reported – “We don’t even have all the questions yet, let alone all the answers.” In part, that is what this workshop is all about. I would love to have your participation in the workshop – either attend in person, or follow the webcast video, and use twitter hashtag of #LunaSE (Lunacy, get it?”) And you can follow me @mlaine.
Also, if you have specific questions, you can ask them here: http://bit.ly/aMJomx
I will answer your questions in a follow-up post.
Thanks for your interest in the project.
Michael J. Laine
President, LiftPort Group
I think that a Lunar Elevator is a brilliant idea!!!
the concept of launching using the moon as a launch point to Mars seems much more feasable to me. Using a Lunar Elevator, rather than launching from the Lunar surface, a Mars mission could launch from Lunar orbit. The lunar elevator could be used to transport fuel and supplies (water) from the lunar surface and an orbiting platform. I don’t know the lagistics of docking with an orbiting station but I have to imagine that they are much less than lagistics of landing on the moon, refueling and launching again. Things dock with the ISS all the time without drama so having a docking platform in Lunar orbit doesn’t seem outside the realm of possibility to me.