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.”
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.”