Space Elevator

  • Posted 01.09.07
  • NOVA scienceNOW

(This video is no longer available for streaming.) It costs about $500 million to take the space shuttle out for a spin. But what if there was another way to get to space? And what if that way were as easy and as cheap as riding an elevator? Well, some people think this kind of trip might be possible someday, thanks to something known as the Space Elevator, a 22,000-mile-long cable that could lift people and payloads straight to outer space.

Running Time: 11:43



PBS Airdate: January 9, 2007

NEIL DEGRASSE TYSON: You're watching NOVA scienceNOW. Still to come on NOVA scienceNOW:

WILLIAM SATURNO: When I shone my flashlight up on the wall, I saw the face of the Maya maize god there. I thought, "Well, I found this amazing thing, and I'm going to die right here, and someone is going to find it and me in 20 years."

NEIL DEGRASSE TYSON: But first, did you ever think about taking a vacation in orbit? Sounds ridiculous, right? Well, when the Space Needle, here in Seattle, was built, in 1962—back at the dawn of the Space Age—lots of people thought they would soon be taking trips just like that.

Of course, hasn't quite worked out that way. It costs about half a billion dollars just to take the space shuttle out for a spin. Kind of an expensive vacation isn't it?

One, please. Thank you.

But what if there was another way to get to space? And what if that way were as easy and as cheap as riding an elevator? Well, strange as it sounds, some people think this kind of trip might just be possible one day, thanks to something known as the Space Elevator, a 22,000-mile long cable that we could ride straight to outer space.

STEPHEN STEINER: What we're talking about is building the biggest thing ever.

NEIL DEGRASSE TYSON: And what enables this big idea is the discovery of something so small, you can't even see it with the naked eye: a new material called a "carbon nanotube." Fueled by the promise of these tiny tubes, people are already working to turn the Space Elevator into a reality.

BRADLEY EDWARDS (Black Line Ascension): It's basically a fairly straightforward system once you get down to the nuts and bolts of it.

First, launch a satellite to geosynchronous orbit, 22,000 miles above Earth. Then, lower a cable or ribbon and attach it to a platform at sea. Clamped to the ribbon, elevator cars, or climbers, could carry people and payloads up and down. Lasers, on the ground, would beam energy wirelessly to solar cells on the underside of the climber, powering electric motors for the 22,000-mile journey.

NEIL DEGRASSE TYSON: Okay, I know what you must be thinking, "A 22,000-mile elevator ride? These people are nuts. Like, what would even hold it up?" Well, the idea is not quite as crazy as it sounds.

STEPHEN STEINER: Imagine I have a yo-yo in my hand. As you spin the yo-yo around, the body of the yo-yo is thrust outward and the string connecting you to the yo-yo is held taut. Well, this is the same principle that would keep the Space Elevator up. We're basically making a planet-sized yo-yo.

NEIL DEGRASSE TYSON: A Space Elevator could be safer and cheaper than rockets, giving routine access to the solar system.

Bringing this far-out idea down to earth, NASA recently funded a competition, in New Mexico, to build and race Space Elevator prototypes. It was held at the X Prize Cup, a carnival of cutting-edge space technology.

In the tradition of competitions that stretch farther back than Charles Lindbergh's transatlantic flight, the aim is to inspire new advances in technology.

This year, teams of students and weekend inventors are vying for the $150,000 in prizes in the Space Elevator contest.

MATTHEW ABRAMS (StarClimber Space Elevator Team): I heard about this competition, and I thought, "Wow! You don't have to have a billion dollars and an aerospace company to do this."

BRIAN TURNER: We're definitely at the cutting edge. You're going to see stuff go wrong today.

NEIL DEGRASSE TYSON: The racetrack is a 50-meter ribbon suspended from a crane. Teams had to design and build climbers, then race them to the top of the ribbon. In place of the laser that might otherwise power a real Space Elevator, they could use only energy from the sun or beamed from the ground.

The best time wins, as long as you go faster than a meter per second.

One of the first to try their luck is a high school team from Germany with an elevator sporting an intimidating solar panel and name.

JOERN LUTAT (Max Born College): Turbocrawler.

NEIL DEGRASSE TYSON: Turbocrawler. All right! That sounds mean. Sounds, sounds like it's going to win.

But as Turbocrawler is about to take off, the wind picks up, Turbocrawler gets out of hand, and the Germans are grounded, at least for the time being.

Julie Bellerose and her team from the University of Michigan are next to jump on the ribbon.

ROGER GILBERTSON (The Spaceward Foundation): The whole big idea behind doing this is to get engineers in school to start working on this. At the end of this event there are kids here who are going to know more about Space Elevator technology than NASA scientists are.

NEIL DEGRASSE TYSON: Julie's climber is powered by a dozen spotlights that each have to track the solar panels all the way up the ribbon.

JULIE BELLEROSE (University of Michigan): Light on!

NEIL DEGRASSE TYSON: The climber gets off to a good start. But the higher it rises, the harder it becomes to hit the solar panels with the spotlights, to keep it going.


NEIL DEGRASSE TYSON: After about 6 minutes of stopping and starting, the climber reaches the top.

JULIE BELLEROSE: We didn't make it in the time required, but I think one of the goals is to make it to the top, so we're very happy.

NEIL DEGRASSE TYSON: NASA's prize money is safe, at least until the contest resumes the next day.

Now, if you think the whole idea of an elevator to space sounds like science fiction, you're right. It was popularized in the late 1970s in a sci-fi novel called The Fountains of Paradise by Arthur C. Clarke.

ARTHUR CLARKE: (Author, The Fountains of Paradise): At last we can build a space elevator. And then we will have a stairway to heaven, a bridge to the stars.

NEIL DEGRASSE TYSON: But as long as people have dreamed of building that bridge to the stars, no material existed to make a cable that's strong enough. That is, until we found that one of nature's most common atoms, carbon, was leading a secret life.

STEPHEN STEINER: I wouldn't say carbon is promiscuous. I would just say it's very open-minded.

NEIL DEGRASSE TYSON: Carbon atoms just love to form extremely strong chemical bonds with one another. We knew they could be arranged in a lattice to form diamond or in sheets to form graphite. But until recently, we had no idea they could also form tiny spheres called "buckyballs" and tiny tubes called "carbon nanotubes."

Much stronger and lighter than steel, and able to conduct electricity, these cylinders of pure carbon have been called a wonder material, a new building block that might be used in everything from electronics to airplanes.

But as a Space Elevator cable, carbon nanotubes have some big problems: the longest ones ever made are only a few centimeters. And joining them together end to end, one at a time, is simply not practical. So how would we ever use these tiny tubes to make a cable that's 22,000 miles long?

Deep in the heart of Texas, scientists are taking a different approach to assembling carbon nanotubes.

RAY BAUGHMAN: It's the dream of the future, but it's an achievable dream.

NEIL DEGRASSE TYSON: To make a batch of carbon nanotubes, bake a silicon plate coated with iron particles, at 1,300 degrees Fahrenheit, in a special oven. Then, add a dash of acetylene, a gas that contains carbon.

When acetylene comes in contact with the iron, it releases its carbon atoms, which assemble—as seen here—into nanotubes.

When the plate comes out, it's coated with a black soot that contains trillions of carbon nanotubes, all aligned vertically in what Ray Baughman calls a "forest."

RAY BAUGHMAN: Think of a bamboo forest.

NEIL DEGRASSE TYSON: But unlike a real bamboo forest, the trees in a nanotube forest tend to stick together, thanks to a faint force operating at the nanoscale called the Van der Waals force. It's sort of like magnetism.

RAY BAUGHMAN: So, when you pull one nanotube out, you pull its neighbors. And then they pull out their neighbors.

NEIL DEGRASSE TYSON: Pulling a whole row of nanotubes from the forest on the left, they can draw out a ribbon of pure carbon nanotubes, held together by nothing but the Van der Waals force.

This ribbon is less than one-thousandth the thickness of a human hair, and it's stronger than steel.

But can nanotube ribbons ever be made strong enough for a Space Elevator cable?

RAY BAUGHMAN: That is an unresolved question, but in science and technology, I've learned to never use the word "never."

NEIL DEGRASSE TYSON: Back in New Mexico, the mood is more optimistic as the second day of the Space Elevator competition gets underway.

Among those hoping to claim NASA's $150,000 prize is Brian Turner, captain of a truly homegrown team, the Kansas City Space Pirates.

BRIAN TURNER: I've got my dad, my step-dad, my mom, my uncle...great-uncle Max.

NEIL DEGRASSE TYSON: Uncle Max. I'm Neil Tyson.

MAX: Neil.

NEIL DEGRASSE TYSON: All right. You're one of the family affair. If you win, that probably means more to you than just getting the money.

MAX: Oh, yeah.

BRIAN TURNER: I don't know. I think...

NEIL DEGRASSE TYSON: Hoping to make their elevator sail up the ribbon, the Space Pirates pull out their secret weapon: 15 mirrors, each the size of a twin bed.

BRIAN TURNER: One person on each mirror.

NEIL DEGRASSE TYSON: Beaming sunlight to your collecting mirror?


NEIL DEGRASSE TYSON: To the solar panel?


NEIL DEGRASSE TYSON: Giving the energy to climb.


ANNOUNCER: Are you ready? All right, here we go.

NEIL DEGRASSE TYSON: Halfway up the ribbon, the wind kicks in again.

BRIAN TURNER: Got to get up there. I'm going to go look at it this way.

NEIL DEGRASSE TYSON: Bouncing in the breeze, the parabolic mirror can't stay focused on the solar cells, and the Pirates' elevator grinds to a halt.

BRIAN TURNER: Come on. Come on.

If the wind hadn't been bucking, I might have been better off. But I can't believe I didn't make it to the top. I figured I could fight my way up there.

NEIL DEGRASSE TYSON: Next up, and favored to win, is the University of Saskatchewan Space Design Team, or USST, for short.

TEAM MEMBER: Go time, right? It's go time.

NEIL DEGRASSE TYSON: Their secret weapon: a stationary mirror to reflect a spotlight straight up the ribbon to the solar array.

TEAM MEMBER: Phase one.

NEIL DEGRASSE TYSON: It looks like they make it to the top in record time, fast enough to claim the $150,000 prize.

So did they win?

BEN SHELEF (The Spaceward Foundation): We have to have a little discussion about that.

NEIL DEGRASSE TYSON: Before the prize money can be awarded, the remaining teams get one last chance.

The German Turbocrawler crawls all the way to the top, but it's no prize winner.

And late in the day, a team of high school students from California posts an impressive two-minute run.

EVAN JOHNSON: It's pretty good that we got 2:02.

JEFFREY GRATTAN: It's going on our resumes.

NEIL DEGRASSE TYSON: But in the end, the prize money went unclaimed, because it turns out Saskatchewan fell just short of the minimum speed of one meter per second.

CLAYTON RUSZKOWSKI (University of Saskatchewan Space Design Team): Next year, most of us are coming back, and we're going to just totally take it up two notches and just go all out.

NEIL DEGRASSE TYSON: But will we ever take a ride in a real Space Elevator?

STEPHEN STEINER: I think it's crazy, but I still think it's possible. And I think it's something that, if we can do it, we should do it.

NEIL DEGRASSE TYSON: Well, one thing's for sure, we have a long way to go before that happens. But, who knows? Perhaps someday technology will catch up with our imaginations and take the Space Elevator out of the realm of science fiction once and for all.


Space Elevator

Edited by
Nathan Hendrie
Written, Produced and Directed by
Joseph McMaster

NOVA scienceNOW

Executive Producer
Samuel Fine
Executive Editor
Neil deGrasse Tyson
Senior Series Producer
Vincent Liota
Supervising Producer
Stephen Sweigart
Editorial Producer
Julia Cort
Development Producer
Vinita Mehta
Program Editor
David Chmura
Post Production Supervisor
Win Rosenfeld
Unit Manager
Candace White
Associate Producers
Mica McCarthy
John Pavlus
Win Rosenfeld
Anna Lee Strachan
Production Secretary
Fran Laks
Brian Edgerton
Yunsik Noh
Edward Marritz
Robert Hanna
Anthony Forma
Peter Bonilla
Stephen McCarthy
Sound Recordists
Alex Sullivan
Michael Karas
Mark Mandler
Steve Jones
Rusty Duggan
Audio Mix
John Jenkins
Jim Ferguson
Vincent Liota
Space elevator animation by Space Elevator Visualization Group
Visual Effects Supervisors
Alan Chan
Lee Stringer
Digital Artists
Eki Halkka
Michael Cliett
Matt Zeyn
Jeff Leroy
Jackson Yuen
Brad Edwards
Additional Editing
Patricia Stern
Win Rosenfeld
Rob Morsberger
NOVA scienceNOW Series Animation
Archival Material
Philip Baird/
Robert Frerck/Odyssey Productions/Chicago
Getty Images
HarperCollins Publishers, Inc. (Arthur Clarke recording)
Longevity Study Participants
Barbara Brody
Irma Daniel
Sylvia Goldberger
Frances Horowitz
Toby Kirsh
Louis Levinson
Arthur Stern
Special Thanks
Harry's Coffee Shop
Mike Jorgenson/WPRB
Jason Saunders
Arthur C. Clarke
Rohan de Silva/The Arthur C. Clarke Foundation
Oak Ridge National Laboratory
Ray Baughman
University of Wollongong
The Space Needle Corporation
Wirefly X PRIZE Cup
LiftPort, Inc.
Neil deGrasse Tyson
is director of the Hayden Planetarium in the Rose Center for Earth and Space at the American Museum of Natural History.
NOVA Series Graphics
yU + co.
NOVA Theme Music
Walter Werzowa
John Luker
Musikvergnuegen, Inc.
Additional NOVA Theme Music
Ray Loring
Post Production Online Editor
Spencer Gentry
Closed Captioning
The Caption Center
NOVA Administrator
Ashley King
Eileen Campion
Anna Lowi
Yumi Huh
Lindsay de la Rigaudiere
Gaia Remerowski
Production Coordinator
Linda Callahan
Unit Manager
Carla Raimer
Raphael Nemes
Legal Counsel
Susan Rosen Shishko
Assistant Editor
Alex Kreuter
Associate Producer Post Production
Patrick Carey
Post Production Supervisor
Regina O'Toole
Post Production Editor
Rebecca Nieto
Post Production Manager
Nathan Gunner
Producers, Special Projects
Susanne Simpson
Lisa Mirowitz
Coordinating Producer
Laurie Cahalane
Senior Science Editor
Evan Hadingham
Senior Series Producer
Melanie Wallace
Managing Director
Alan Ritsko
Senior Executive Producer
Paula S. Apsell

This material is based upon work supported by the National Science Foundation under Grant No. 0229297. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

NOVA scienceNOW is a trademark of the WGBH Educational Foundation

NOVA scienceNOW is produced for WGBH/Boston by NOVA

© 2007 WGBH Educational Foundation

All rights reserved

Image credit: (space elevator) Courtesy Bradley C. Edwards/Space Elevator Visualization Group


Evan Johnson & Jeffrey Grattan
Westmont High School
Matthew Abrams
Ray Baughman
The University of Texas at Dallas
Julie Bellerose
University of Michigan
Bradley Edwards
Black Line Ascension
Ken Elliot
University of Saskatchewan Space Design Team
Roger Gilbertson
The Spaceward Foundation
Joern Lutat
Max Born College
Clayton Ruszkowski
University of Saskatchewan Space Design Team
Ben Shelef
The Spaceward Foundation
Stephen Steiner
Massachusetts Institute of Technology
Brian Turner
Kansas City Space Pirates

Related Links