INDEPTH: SPACE
Space Elevator: Next floor, Mars
CBC News Online | Updated October 2006
Sometimes breakthrough science can happen during a simple coffee break, at least it can at the U.S. Los Alamos National Laboratory in New Mexico where it's possible to eavesdrop on some big brains hatching a bold scheme that will transform the planet.
| SPACE ELEVATOR CONTEST |
On Oct. 21, 2005, Elevator: 2010, a project headed by the California-based Spaceward Foundation, launched its annual competition for space-elevator technologies, modeled after high-tech challenges such as the $10 million US Ansari X Prize.
The prize money, provided by NASA's Centennial Challenges program, amounts to a total of $4 million US over the next five years.
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They're calculating nothing less than the ultimate conquest of the universe.
Their idea? They intend to build a fixed link into outer space.
Right now, the only way into space is to be strapped to a rocket. It will boost a satellite or a shuttle into orbit, but it's like getting into space on the back of a bomb. It's dangerous, it's expensive and no one has ever been able to use a rocket twice.
What if there were a better way, a ribbon slicing through the atmosphere that spacecraft could climb? An extreme version of an elevator that's right out of science fiction by writers like Arthur C. Clarke.
As long as man has been able to stare at the stars the idea has been there, in Jacob's ladder, in the Tower of Babel. It was a mystical dream of something tall enough to reach into the heavens.
It would be a revolution, and out here in this remote part of New Mexico scientists have already launched one revolution. Now 60 years later they're planning another one.
In 1941, the world's greatest physicists gathered at Los Alamos, in secret, to build the atomic bomb. They were hidden away, courtesy of the U.S. government, under the code name the Manhattan Project. When they finished, they had packed the power of the atom into a weapon so awesome that it ended a war and launched the nuclear age.
Since then, Los Alamos has continued to draw big brains with big ideas to a thriving centre of military and industrial science.
Now, there's another idea percolating here, an idea just as big, with implications just as profound. But there's no big government this time. Just a few passionate scientists working on their own, for free, in their spare time.
Meet astrophysicist Bryan Laubscher.
Space elevator (Courtesy: Los Alamos National Laboratory)
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"The whole beanstalk idea and the whole idea of putting a ribbon into space and just climbing it is a hard concept to sell to people on Earth who are used to rockets," he says. "That's the way to get into space, a man's way. Climb in there and they light that thing and hope it doesn't blow up."
There's Ron Morgan, health physicist. He admits he's obsessed.
"We're definitely on the ground floor," he says. "I think of a project that is going to change the world, absolutely. I believe that we could have the first Earth to space elevator in 12 to 15 years."
And Mervyn Kellum. He's studying the business opportunities that would open up if the elevator made space travel suddenly easy.
"It's a concept where we can dramatically lower the transportation costs, access to space," Kellum says.
The space elevator starts with a basic platform in the ocean, near the equator. Attached to the platform is a paper-thin ribbon no more than a metre wide that stretches 100,000 kilometres into space, about one-quarter of the way to the moon. There it's tied to a satellite that pulls the ribbon taut and keeps it straight as it orbits in synch with the Earth's rotation.
"The idea is somewhat like taking a ball on a string, spinning it around in your hand," Laubscher says. "It doesn't just flop down, it actually opposes the force of gravity and stands outward. That's really what's happening with this cable."
Spacecraft would ride up the cable on an electrically powered climber that would be fuelled by ground-based lasers shining onto solar panels.
Once above the Earth's atmosphere the spacecraft would be released to orbit the Earth and do whatever business it was sent to do. Or it could ride the elevator right to the end and be thrown toward Mars or Venus.
"It helps to be a scientist rather than a science fiction writer," Laubscher says. "It helps that carbon nanotubes are known. That really helps a lot. And it maybe helps being at Los Alamos."
Carbon nanotubes?
Until 10 years ago, there was nothing to build a space elevator with. It would take every scrap of steel on the face of the planet and the thing would be huge and impossibly heavy.
So scientists were forced to fantasize about a space elevator built with a magic material they called "unobtainium."
Then, in 1991, scientists discovered carbon nanotubes. They're hollow carbon tubes 100 times stronger than steel yet so tiny 50,000 of them would fit inside a human hair.
There can be millions of carbon nanontubes in a petrie dish. For scientists, the discovery of this new form of carbon was a tantalizing surprise and they're rushing to exploit the possibilities of a molecule that has all the strength of a diamond yet is six times lighter than steel.
"Think about a soccer ball," Morgan says. "Sixty carbon atoms can arrange themselves into a soccer ball that's a very strong shape. Think about them then adding carbons in rings and stretching out the ends of that ball. This is what carbon nanotubes look like. They do have the right strength-to-weight ratio, properties. To actually build a cable you just have to work on them. It's kind of an engineering problem."
Elevator base (Courtesy: Los Alamos National Laboratory)
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Ron Morgan keeps an eager eye on all the fully funded carbon nanotube research going on at Los Alamos as other scientists search for military and industrial applications. Their focus is different, but Morgan knows every breakthrough they make in carbon nanotubes brings his beloved space elevator a little bit closer to reality.
"We have people literally all over the world looking at how you build high quality nanotubes," Morgan says. "Once we get 650 tons of high quality nanotube and are able to bind them together in sections to form a cable – and that's not going to be easy, that's very difficult to do right now – but once we have that material in place, the manufacturing techniques in place to build the space elevator, we can launch it in a matter of two years."
Yuntian Zhu is trying to figure out a way to stretch carbon nanotubes. Right now the longest one he can make is just 1½ centimetres.
For the space elevator, the carbon nanotubes need to be many metres long and woven together in a polymer to make a super-strong cable.
"You'd be basically spinning a long fibre out that's composed of many millions of nanotubes," Morgan says.
Scientists are still trying to understand the properties of this new material. There's a health issue. Are carbon nanotubes safe to breathe? What if something cut the space elevator cable sending bits of carbon nanotubes into the air? Even though no one has asked him to, and no one is paying him, Ron Morgan has decided to find out how dangerous a carbon nanotube blowout might be.
"I haven't been able to find anybody who can tell me definitely what those pieces of cable will do," Morgan says. "But you can almost bet that they'll burn up in the atmosphere at least to some degree. Carbon nanotubes are extremely refractory tubes, and by that I mean they're tough, very tough and very small, and it's possible that when they come down and burn up that they will burn up in pieces small enough to inhale. Anybody who has looked at it knows that there's going to have to be a lot of research on the potential health effects."
It might be worse if the cable didn't break up and instead collapsed and came tumbling back to Earth.
"If the whole thing fell somehow like you cut it at the counterweight, cut it way up at the counterweight, it would wrap around the Earth a couple of times," Laubscher says. "If it didn't come apart, I think upon reentering a lot of it would burn up. But I can't say a lot because we didn't have the resources yet to study that."
Elevator base (Courtesy: Los Alamos National Laboratory)
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So you could be looking at a space elevator ribbon that's wrapped around the Earth a couple of times.
That would be the worst-case scenario. It wouldn't be a good situation if you were in the way.
So it will be crucial to keep the elevator out of harm's way; to avoid roaming satellites the scientists intend to keep moving the ocean platform, probably several times a day. Asteroids and space junk are also hazards, but if the space elevator eliminated rockets there would be less debris floating in space.
They concede there is something else to consider these days. In the post-9/11 world, the first space elevator, built by the United States, would be a tempting target for terrorism.
"I just said, well, you know, put it out in the ocean and the U.S. navy will defend it," Laubscher says. "Someone pointed out to me, well, they can defend it to a certain altitude. Then what are we going to do? So I've been thinking about that. You know, some terrorist nation could launch a rocket that could strike the space elevator, first time, first pass. That would be a great achievement because it is very small in cross-section it is very thin."
All of the elevator rides on Earth now – even the longest ones like the one at Toronto's CN Tower – are over in a matter of moments. For people going up the space elevator the ride will take more than a week and they will spend days passing through a belt of heavy radiation before reaching the top. So that's another problem. The passenger car must be designed to shield travellers from those deadly radioactive beams.
Elevator base (Courtesy: Los Alamos National Laboratory)
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Despite all the daunting problems that face them, the space elevator enthusiasts say with research, time and money, they'll find a solution.
They insist that one day there will be lots of elevators ferrying satellites, prospectors and even tourists into space. They say the benefits of having them in space will be worth all the efforts.
Right now the cost of getting into space is one of the major blocks to more exploration. Mervyn Kellum has done studies on the cost of transportation comparing rockets to the space elevator.
The space elevator could break down the biggest barrier separating humans from the fortunes of space. Kellum says rocket travel is so expensive only governments and the military can afford to go up.
"Right now transportation costs are somewhere around $20,000 a kilogram," Kellum says. "The cheapest we can get to low Earth orbit is about $5,000 a kilogram. If we can get the space elevator up and functioning we may be able to get it down to $100 a kilogram. Now we're talking about something that now I can do business in space cheaply."
He believes cheap space travel will be good for the Earth with manufacturing and mining in space, with orbiting solar collectors that could send energy from the sun to anywhere on the planet.
So this is the dream: build an elevator into space and suddenly anything is possible.
"Actually it's very easy to put a space elevator on Mars once we get the one on Earth," Morgan says.
A powerful red laser (bottom left) could push the elevator into space (Courtesy: Los Alamos National Laboratory)
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"Then you bring your spacecraft, up the space elevator and let it go at the end of the elevator, let it drift to Mars, pick it up with the outward end of the Mars elevator and take it [the spacecraft] down to Mars.
"Then they come up the Mars elevator, wait to the auspicious moment, let it go from the end of the Mars elevator. It comes over into Earth orbit …and connects to the top of the Earth elevator and down you go. You've never used a drop of rocket fuel."
Could it ever really happen? For a generation that watched a man walk on the moon, anything is possible. But the Apollo missions were 30 years ago and since then the nation's dream to conquer space has fizzled.
"There was an enthusiasm about space; we were in charge of our own destiny and there wasn't anything that we couldn't do," Kellum says. "We don't have that in this country anymore and haven't had it for quite a long time. I [would] kind of like for us to get it back and I see the space elevator as a vehicle by which we can do that."
First they have to get the government's attention for a project that will cost $6 billion. The space elevator team sees hope in the announcement that U.S. President George W. Bush wants to send America to the moon and Mars, now that China's moving quickly forward. The Columbia disaster reminded everyone that the shuttle program is creaking with age.
Brad Edwards is a rare breed – a scientist who has direct funding for space elevator research that resulted in writing a how-to book on building the first one. Edwards believes Bush's mission can only be good news for his project.
"On the time scales they're talking about, it's very conceivable that NASA will choose for a rocket option to go to the moon and Mars and not choose the space elevator," Edwards says. "However, if a program like that gets started it will demonstrate the value and interest, and we at NASA will be looking at new technologies.
Nanotubes seen through an electron microscope (Courtesy: Los Alamos National Laboratory)
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"It's sort of like everyone else is walking and you own an automobile. It's a dramatic transportation system. You could own the land beyond walking distance and it's the same thing here. You can access parts of space the rest of the world can't."
In this new climate, Edwards will be getting more money this year, millions from NASA and Congress to continue his work. It seems they've heard his message that whoever builds the space elevator first will own space.
It's a construction project with no precedent. It would be bigger than anything mankind has attempted to build before. But there is precedent for the vision. Two centuries ago they imagined another thin ribbon that would span an enormous distance, that would change the world. There was a time when a cross-country railroad seemed like an impossible dream.
"The whole country wanted a transcontinental railroad," Edwards says. "Kind of had this understanding at the grassroots level that this was a good thing. The transcontinental railroad was so lucrative that the government gave these people a lot of resources. As soon as they scouted the last routes through the mountains of California they knew they had the route. As soon as they had [the route] they started building. So I feel the same thing with the space elevator: as soon as we can build it we need to build it."
Diagram of the structure of a nanotube (Courtesy: Los Alamos National Laboratory)
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"I've been intrigued by being in space but I also recognize that they don't take many people up, and if I'm going to be one of the people, well, maybe we ought to lower the cost," Kellum says.
The plan is to get business interested in building a space elevator so they can use it to make money which will make it cheaper to get into space.
Is that realistic?
"I think so," says Kellum. "Otherwise I wouldn't be doing this."
And would the others go? The answer for every one of them is the same. In a heartbeat.
With files from The National's Kelly Crowe and producer Debie Goodwin. Original air date: Feb. 24, 2004
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