May 31, 2010

A Space Elevator in 7

Posted by in categories: nanotechnology, space

I am a former Microsoft programmer who wrote a book (for a general audience) about the future of software called After the Software Wars. Eric Klien has invited me to post on this blog (Software and the Singularity, AI and Driverless cars) Here are the sections on the Space Elevator. I hope you find these pages food for thought and I appreciate any feedback.

A Space Elevator in 7

Midnight, July 20, 1969; a chiaroscuro of harsh contrasts appears on the television screen. One of the shadows moves. It is the leg of astronaut Edwin Aldrin, photographed by Neil Armstrong. Men are walking on the moon. We watch spellbound. The earth watches. Seven hundred million people are riveted to their radios and television screens on that July night in 1969. What can you do with the moon? No one knew. Still, a feeling in the gut told us that this was the greatest moment in the history of life. We were leaving the planet. Our feet had stirred the dust of an alien world.

—Robert Jastrow, Journey to the Stars

Management is doing things right, Leadership is doing the right things!

—Peter Drucker

SpaceShipOne was the first privately funded aircraft to go into space, and it set a number of important “firsts”, including being the first privately funded aircraft to exceed Mach 2 and Mach 3, the first privately funded manned spacecraft to exceed 100km altitude, and the first privately funded reusable spacecraft. The project is estimated to have cost $25 million dollars and was built by 25 people. It now hangs in the Smithsonian because it serves no commercial purpose, and because getting into space is no longer the challenge — it is the expense.

In the 21st century, more cooperation, better software, and nanotechnology will bring profound benefits to our world, and we will put the Baby Boomers to shame. I focus only on information technology in this book, but materials sciences will be one of the biggest tasks occupying our minds in the 21st century and many futurists say that nanotech is the next (and last?) big challenge after infotech.

I’d like to end this book with one more big idea: how we can jump-start the nanotechnology revolution and use it to colonize space. Space, perhaps more than any other endeavor, has the ability to harness our imagination and give everyone hope for the future. When man is exploring new horizons, there is a swagger in his step.

Colonizing space will change man’s perspective. Hoarding is a very natural instinct. If you give a well-fed dog a bone, he will bury it to save it for a leaner day. Every animal hoards. Humans hoard money, jewelry, clothes, friends, art, credit, books, music, movies, stamps, beer bottles, baseball statistics, etc. We become very attached to these hoards. Whether fighting over $5,000 or $5,000,000 the emotions have the exact same intensity.

When we feel crammed onto this pale blue dot, we forget that any resource we could possibly want is out there in incomparably big numbers. If we allocate the resources merely of our solar system to all 6 billion people equally, then this is what we each get:

Resource Amount
Hydrogen 34,000 billion Tons
Iron 834 billion Tons
Silicates (sand, glass) 834 billion Tons
Oxygen 34 billion Tons
Carbon 34 billion Tons
Energy production 64 trillion Kilowatts per hour

Even if we confine ourselves only to the resources of this planet, we have far more than we could ever need. This simple understanding is a prerequisite for a more optimistic and charitable society, which has characterized eras of great progress. Unfortunately, NASA’s current plans are far from adding that swagger.

If NASA follows through on its 2004 vision to retire the Space Shuttle and go back to rockets, and go to the moon again, this is NASA’s own imagery of what we will be looking at on in 2020.

Our astronauts will still be pissing in their space suits in 2020.

According to NASA, the above is what we will see in 2020, but if you squint your eyes, it looks just like 1969:

All this was done without things we would call computers.

Only a government bureaucracy can make such little progress in 50 years and consider it business as usual. There are many documented cases of large government organizations plagued by failures of imagination, yet no one considers that the rocket-scientist-bureaucrats at NASA might also be plagued by this affliction. This is especially ironic because the current NASA Administrator, Michael Griffin, has admitted that many of its past efforts were failures:

  • The Space Shuttle, designed in the 1970s, is considered a failure because it is unreliable, expensive, and small. It costs $20,000 per pound of payload to put into low-earth orbit (LEO), a mere few hundred miles up.
  • The International Space Station (ISS) is small, and only 200 miles away, where gravity is 88% of that at sea-level. It is not self-sustaining and doesn’t get us any closer to putting people on the moon or Mars. (By moving at 17,000 miles per hour, it falls fast enough to stay in the same orbit.) America alone spent $100 billion on this boondoggle.

The key to any organization’s ultimate success, from NASA to any private enterprise, is that there are leaders at the top with vision. NASA’s mistakes were not that it was built by the government, but that the leaders placed the wrong bets. Microsoft, by contrast, succeeded because Bill Gates made many smart bets. NASA’s current goal is “flags and footprints”, but their goal should be to make it cheap to do those things, a completely different objective.1

I don’t support redesigning the Space Shuttle, but I also don’t believe that anyone at NASA has seriously considered building a next-generation reusable spacecraft. NASA is basing its decision to move back to rockets primarily on the failures of the first Space Shuttle, an idea similar to looking at the first car ever built and concluding that cars won’t work.

Unfortunately, NASA is now going back to technology even more primitive than the Space Shuttle. The “consensus” in the aerospace industry today is that rockets are the future. Rockets might be in our future, but they are also in the past. The state-of-the-art in rocket research is to make them 15% more efficient. Rocket research is incremental today because the fundamental chemistry and physics hasn’t changed since their first launches in the mid-20th century.

Chemical rockets are a mistake because the fuel which propels them upward is inefficient. They have a low “specific impulse”, which means it takes lots of fuel to accelerate the payload, and even more more fuel to accelerate that fuel! As you can see from the impressive scenes of shuttle launches, the current technology is not at all efficient; rockets typically contain 6% payload and 94% overhead. (Jet engines don’t work without oxygen but are 15 times more efficient than rockets.)

If you want to know why we have not been back to the moon for decades, here is an analogy:

What would taking delivery of this car cost you?
A Californian buys a car made in Japan.
The car is shipped in its own car carrier.
The car is off-loaded in the port of Los Angeles.
The freighter is then sunk.

The latest in propulsion technology is electrical ion drives which accelerate atoms 20 times faster than chemical rockets, which mean you need much less fuel. The inefficiency of our current chemical rockets is what is preventing man from colonizing space. Our simple modern rockets might be cheaper than our complicated old Space Shuttle, but it will still cost thousands of dollars per pound to get to LEO, a fancy acronym for 200 miles away. Working on chemical rockets today is the technological equivalent of polishing a dusty turd, yet this is what our esteemed NASA is doing.

The Space Elevator

When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

—Arthur C. Clarke RIP, 1962

The best way to predict the future is to invent it. The future is not laid out on a track. It is something that we can decide, and to the extent that we do not violate any known laws of the universe, we can probably make it work the way that we want to. —Alan Kay

A NASA depiction of the space elevator. A space elevator will make it hundreds of times cheaper to put a pound into space. It is an efficiency difference comparable to that between the horse and the locomotive.

One of the best ways to cheaply get back into space is kicking around NASA’s research labs:

Scale picture of the space elevator relative to the size of Earth. The moon is 30 Earth-diameters away, but once you are at GEO, it requires relatively little energy to get to the moon, or anywhere else.

A space elevator is a 65,000-mile tether upon which we can launch things into space in a slow, safe, and cheap way.

And these climbers don’t even need to carry their energy as you can use solar panels to provide the energy for the climbers. All this means you need much less fuel. Everything is fully reusable, so when you have built such a system, it is easy to have daily launches.

The first elevator’s climbers will travel into space at just a few hundred miles per hour — a very safe speed. Building a device which can survive the acceleration and jostling is a large part of the expense of putting things into space today. This technology will make it hundreds, and eventually thousands of times cheaper to put things, and eventually people, into space.

A space elevator might sound like science fiction, but like many of the ideas of science fiction, it is a fantasy that makes economic sense. While you needn’t trust my opinion on whether a space elevator is feasible, NASA has never officially weighed in on the topic — also a sign they haven’t given it serious consideration.

This all may sound like science fiction, but compared to the technology of the 1960s, when mankind first embarked on a trip to the moon, a space elevator is simple for our modern world to build. In fact, if you took a cellphone back to the Apollo scientists, they’d treat it like a supercomputer and have teams of engineers huddled over it 24 hours a day. With only the addition of the computing technology of one cellphone, we might have shaved a year off the date of the first moon landing.

Carbon Nanotubes

Nanotubes are Carbon atoms in the shape of a hexagon. Graphic created by Michael Ströck.

We have every technological capability necessary to build a space elevator with one exception: carbon nanotubes (CNT). To adapt a line from Thomas Edison, a space elevator is 1% inspiration, and 99% perspiration.

Carbon nanotubes are extremely strong and light, with a theoretical strength of three million kilograms per square centimeter; a bundle the size of a few hairs can lift a car. The theoretical strength of nanotubes is far greater than what we would need for our space elevator; current baseline designs specify a paper-thin, 3-foot-wide ribbon. These seemingly flimsy dimensions would be strong enough to support their own weight, and the 10-ton climbers using the elevator.

The nanotubes we need for our space elevator are the perfect place to start the nanotechnology revolution because, unlike biological nanotechnology research, which uses hundreds of different atoms in extremely complicated structures, nanotubes have a trivial design.

The best way to attack a big problem like nanotechnology is to first attack a small part of it, like carbon nanotubes. A “Manhattan Project” on general nanotechnology does not make sense because it is too unfocused a problem, but such an effort might make sense for nanotubes. Or, it might simply require the existing industrial expertise of a company like Intel. Intel is already experimenting with nanotubes inside computer chips because metal loses the ability to conduct electricity at very small diameters. But no one has asked them if they could build mile-long ropes.

The US government has increased investments in nanotechnology recently, but we aren’t seeing many results. From space elevator expert Brad Edwards:

There’s what’s called the National Nanotechnology Initiative. When I looked into it, the budget was a billion dollars. But when you look closer at it, it is split up between a dozen agencies, and within each agency it’s split again into a dozen different areas, much of it ends up as $100,000 grants. We looked into it with regards to carbon nanotube composites, and it appeared that about thirty million dollars was going into high-strength materials — and a lot of that was being spent internally in a lot of the agencies; in the end there’s only a couple of million dollars out of the billion-dollar budget going into something that would be useful to us. The money doesn’t have focus, and it’s spread out to include everything. You get a little bit of effort in a thousand different places. A lot of the budget is spent on one entity trying to play catch-up with whoever is leading. Instead of funding the leader, they’re funding someone else internally to catch up.

Again, here is a problem similar to the one we find in software today: people playing catchup rather than working together. I don’t know what nanotechnology scientists do every day, but it sounds like they would do well to follow in the footsteps of our free software pioneers and start cooperating.

The widespread production of nanotubes could be the start of a nanotechnology revolution. And the space elevator, the killer app of nanotubes, will enable the colonization of space.


William Bradford, speaking in 1630 of the founding of the Plymouth Bay Colony, said that all great and honorable actions are accompanied with great difficulties, and both must be enterprised and overcome with answerable courage.

There is no strife, no prejudice, no national conflict in outer space as yet. Its hazards are hostile to us all. Its conquest deserves the best of all mankind, and its opportunity for peaceful cooperation may never come again. But why, some say, the moon? Why choose this as our goal? And they may well ask why climb the highest mountain? Why, 35 years ago, fly the Atlantic? Why does Rice play Texas?

We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too.

It is for these reasons that I regard the decision last year to shift our efforts in space from low to high gear as among the most important decisions that will be made during my incumbency in the office of the Presidency.

In the last 24 hours we have seen facilities now being created for the greatest and most complex exploration in man’s history. We have felt the ground shake and the air shattered by the testing of a Saturn C-1 booster rocket, many times as powerful as the Atlas which launched John Glenn, generating power equivalent to 10,000 automobiles with their accelerators on the floor. We have seen the site where five F-1 rocket engines, each one as powerful as all eight engines of the Saturn combined, will be clustered together to make the advanced Saturn missile, assembled in a new building to be built at Cape Canaveral as tall as a 48 story structure, as wide as a city block, and as long as two lengths of this field.

The growth of our science and education will be enriched by new knowledge of our universe and environment, by new techniques of learning and mapping and observation, by new tools and computers for industry, medicine, the home as well as the school.

I do not say that we should or will go unprotected against the hostile misuse of space any more than we go unprotected against the hostile use of land or sea, but I do say that space can be explored and mastered without feeding the fires of war, without repeating the mistakes that man has made in extending his writ around this globe of ours.

We have given this program a high national priority — even though I realize that this is in some measure an act of faith and vision, for we do not now know what benefits await us. But if I were to say, my fellow citizens, that we shall send to the moon, 240,000 miles away from the control station in Houston, a giant rocket more than 300 feet tall, the length of this football field, made of new metal alloys, some of which have not yet been invented, capable of standing heat and stresses several times more than have ever been experienced, fitted together with a precision better than the finest watch, carrying all the equipment needed for propulsion, guidance, control, communications, food and survival, on an untried mission, to an unknown celestial body, and then return it safely to earth, re-entering the atmosphere at speeds of over 25,000 miles per hour, causing heat about half that of the temperature of the sun — almost as hot as it is here today — and do all this, and do it right, and do it first before this decade is out — then we must be bold.

John F. Kennedy, September 12, 1962

Lunar Lander at the top of a rocket. Rockets are expensive and impose significant design constraints on space-faring cargo.

NASA has 18,000 employees and a $17-billion-dollar budget. Even with a fraction of those resources, their ability to oversee the design, handle mission control, and work with many partners is more than equal to this task.

If NASA doesn’t build the space elevator, someone else might, and it would change almost everything about how NASA does things today. NASA’s tiny (15-foot-wide) new Orion spacecraft, which was built to return us to the moon, was designed to fit atop a rocket and return the astronauts to Earth with a 25,000-mph thud, just like in the Apollo days. Without the constraints a rocket imposes, NASA’s spaceship to get us back to the moon would have a very different design. NASA would need to throw away a lot of the R&D they are now doing if a space elevator were built.

Another reason the space elevator makes sense is that it would get the various scientists at NASA to work together on a big, shared goal. NASA has recently sent robots to Mars to dig two-inch holes in the dirt. That type of experience is similar to the skills necessary to build the robotic climbers that would climb the elevator, putting those scientists to use on a greater purpose.

Space debris is a looming hazard, and a threat to the ribbon:

Map of space debris. The US Strategic Command monitors 10,000 large objects to prevent them from being misinterpreted as a hostile missile. China blew up a satellite in January, 2007 which created 35,000 pieces of debris larger than 1 centimeter.

The space elevator provides both a motive, and a means to launch things into space to remove the debris. (The first elevator will need to be designed with an ability to move around to avoid debris!)

Once you have built your first space elevator, the cost of building the second one drops dramatically. A space elevator will eventually make it $10 per pound to put something into space. This will open many doors for scientists and engineers around the globe: bigger and better observatories, a spaceport at GEO, and so forth.

Surprisingly, one of the biggest incentives for space exploration is likely to be tourism. From Hawaii to Africa to Las Vegas, the primary revenue in many exotic places is tourism. We will go to the stars because man is driven to explore and see new things.

Space is an extremely harsh place, which is why it is such a miracle that there is life on Earth to begin with. The moon is too small to have an atmosphere, but we can terraform Mars to create one, and make it safe from radiation and pleasant to visit. This will also teach us a lot about climate change, and in fact, until we have terraformed Mars, I am going to assume the global warming alarmists don’t really know what they are talking about yet.2 One of the lessons in engineering is that you don’t know how something works until you’ve done it once.

Terraforming Mars may sound like a silly idea today, but it is simply another engineering task.3 I worked in several different groups at Microsoft, and even though the set of algorithms surrounding databases are completely different from those for text engines, they are all engineering problems and the approach is the same: break a problem down and analyze each piece. (One of the interesting lessons I learned at Microsoft was the difference between real life and standardized tests. In a standardized test, if a question looks hard, you should skip it and move on so as not to waste precious time. At Microsoft, we would skip past the easy problems and focus our time on the hard ones.)

Engineering teaches you that there are an infinite number of ways to attack a problem, each with various trade-offs; it might take 1,000 years to terraform Mars if we were to send one ton of material, but only 20 years if we could send 1,000 tons of material. Whatever we finally end up doing, the first humans to visit Mars will be happy that we turned it green for them. This is another way our generation can make its mark.

A space elevator is a doable mega-project, but there is no progress beyond a few books and conferences because the very small number of people on this planet who are capable of initiating this project are not aware of the feasibility of the technology.

Brad Edwards, one of the world’s experts on the space elevator, has a PhD and a decade of experience designing satellites at Los Alamos National Labs, and yet he has told me that he is unable to get into the doors of leadership at NASA, or the Gates Foundation, etc. No one who has the authority to organize this understands that a space elevator is doable.

Glenn Reynolds has blogged about the space elevator on his very influential, yet a national dialog about this topic has not yet happened, and NASA is just marching ahead with its expensive, dim ideas. My book is an additional plea: one more time, and with feeling!

How and When

It does not follow from the separation of planning and doing in the analysis of work that the planner and the doer should be two different people. It does not follow that the industrial world should be divided into two classes of people: a few who decide what is to be done, design the job, set the pace, rhythm and motions, and order others about; and the many who do what and as they are told.

—Peter Drucker

There are a many interesting details surrounding a space elevator, and for those interested in further details, I recommend The Space Elevator, co-authored by Brad Edwards.

The size of the first elevator is one of biggest questions to resolve. If you were going to lay fiber optic cables across the Atlantic ocean, you’d set aside a ton of bandwidth capacity. Likewise, the most important metric for our first space elevator is its size. I believe at least 100 tons / day is a worthy requirement, otherwise the humans will revert to form and start hoarding the cargo space.

The one other limitation with current designs is that they assume climbers which travel hundreds of miles per hour. This is a fine speed for cargo, but it means that it will take days to get into orbit. If we want to send humans into space in an elevator, we need to build climbers which can travel at least 10,000 miles per hour. While this seems ridiculously fast, if you accelerate to this speed over a period of minutes, it will not be jarring. Perhaps this should be the challenge for version two if they can’t get it done the first time.

The conventional wisdom amongst those who think it is even possible is that it will take between 20 and 50 years to build a space elevator. However, anyone who makes such predictions doesn’t understand that engineering is a fungible commodity. I can just presume they must never had the privilege of working with a team of 100 people who in 3 days accomplish as much as you will in a year. Two people will, in general, accomplish something twice as fast as one person.4 How can you say something will unequivocally take a certain amount of time when you don’t specify how many resources it will require or how many people you plan to assign to the task?

Furthermore, predictions are usually way off. If you asked someone how long it would take unpaid volunteers to make Wikipedia as big as the Encyclopedia Britannica, no one would have guessed the correct answer of two and a half years. From creating a space elevator to world domination by Linux, anything can happen in far less time than we think is possible if everyone simply steps up to play their part. The way to be a part of the future is to invent it, by unleashing our scientific and creative energy towards big, shared goals. Wikipedia, as our encyclopedia, was an inspiration to millions of people, and so the resources have come piling in. The way to get help is to create a vision that inspires people. In a period of 75 years, man went from using horses and wagons to landing on the moon. Why should it take 20 years to build something that is 99% doable today?

Many of the components of a space elevator are simple enough that college kids are building prototype elevators in their free time. The Elevator:2010 contest is sponsored by NASA, but while these contests have generated excitement and interest in the press, they are building toys, much like a radio-controlled airplane is a toy compared to a Boeing airliner.

I believe we could have a space elevator built in 7 years. If you divvy up five years of work per person, and add in a year to ramp up and test, you can see how seven years is quite reasonable. Man landed on the moon 7 years after Kennedy’s speech, exactly as he ordained, because dates can be self-fulfilling prophecies. It allows everyone to measure themselves against their goals, and determine if they need additional resources. If we decided we needed an elevator because our civilization had a threat of extermination, one could be built in a very short amount of time.

If the design of the hardware and the software were done in a public fashion, others could take the intermediate efforts and test them and improve them, therefore saving further engineering time. Perhaps NASA could come up with hundreds of truly useful research projects for college kids to help out on instead of encouraging them to build toys. There is a lot of software to be written and that can be started now.

The Unknown Unknown is the nanotubes, but nearly all the other pieces can be built without having any access to them. We will only need them wound into a big spool on the launch date.

I can imagine that any effort like this would get caught up in a tremendous amount of international political wrangling that could easily add years on to the project. We should not let this happen, and we should remind each other that the space elevator is just the railroad car to space — the exciting stuff is the cargo inside and the possibilities out there. A space elevator is not a zero sum endeavor: it would enable lots of other big projects that are totally unfeasible currently. A space elevator would enable various international space agencies that have money, but no great purpose, to work together on a large, shared goal. And as a side effect it would strengthen international relations.5

1 The Europeans aren’t providing great leadership either. One of the big investments of their Space agencies, besides the ISS, is to build a duplicate GPS satellite constellation, which they are doing primarily because of anti-Americanism! Too bad they don’t realize that their emotions are causing them to re-implement 35 year-old technology, instead of spending that $5 Billion on a truly new advancement. Cloning GPS in 2013: Quite an achievement, Europe!

2 Carbon is not a pollutant and is valuable. It is 18% of the mass of the human body, but only .03% of the mass of the Earth. If Carbon were more widespread, diamonds would be cheaper. Driving very fast cars is the best way to unlock the carbon we need. Anyone who thinks we are running out of energy doesn’t understand the algebra in E = mc2.

3 Mars’ moon, Phobos, is only 3,700 miles above Mars, and if we create an atmosphere, it will slow down and crash. We will need to find a place to crash the fragments, I suggest in one of the largest canyons we can find; we could put them next to a cross dipped in urine and call it the largest man-made art.

4 Fred Brooks’ The Mythical Man-Month argues that adding engineers late to a project makes a project later, but ramp-up time is just noise in the management of an engineering project. Also, wikis, search engines, and other technologies invented since his book have lowered the overhead of collaboration.

5 Perhaps the Europeans could build the station at GEO. Russia could build the shuttle craft to move cargo between the space elevator and the moon. The Middle East could provide an electrical grid for the moon. China could take on the problem of cleaning up the orbital space debris and build the first moon base. Africa could attack the problem of terraforming Mars, etc.


Comments — comments are now closed.

  1. Very fine article — thanks! I directed my 17-yr old to it, he has hopes of being an aerospace engineer and a goal like the Space Elevator is inspiring.

    I wish you had left the last bit off of footnote #3; it seems gratuitously offensive.

  2. Keith Curtis says:

    Hi binkley;

    I was trying to think of a way to make the fragments into art and that one occurred to me.

    The backstory: professional artists in the US have said that such a thing was artwork worthy of government funding!

    It was a joke that we live in an age that professional artists consider such stuff valid. I will look at it again to at least make it clear I don’t personally advocate this.

    Thanks for the feedback. I’m hoping many get the reference, but I could be wrong.


  3. David says:

    Kilowatts per hour? No.

  4. Andy Maher says:

    Sad that the elevator is still science fiction. I’ve been watching the “progress” for years. And the art reference is, also sadly, valid.

  5. Doug Collins says:

    -The space debris is being thought of as waste. That seems wrong to me. It is made up of a lot of exotic materials and, at least until there are a lot of cheap space elevators in operation, it has the huge value of already being out of the gravity well. Glenn Reynolds has said that the biggest problem is that there is no space salvage law at present. You can’t take possession if you can grab it.

    From KeithCu: With a space elevator it becomes a lot cheaper to put a pound into space, which makes everything up there much less valuable. It is like salvaging through a junkyard. Best to just clean it up.

  6. Doug Collins says:

    I don’t understand the need to travel at 10,000s of miles/hour. If LEO is only 200 miles, even 20,000 miles would be just a day or so of riding. For tourism, assuming the elevator car has windows, the ride would be half the experience.

    From Keith: I was talking about getting to the station at GEO.

  7. Martin L. Shoemaker says:

    While I’m all for a practical space elevator — and you make it sound more practical here than in any article I’ve read before — I want to speak in defense of rockets. You write of the 15% improvement in rocket fuel efficiency, and also the superior efficiency of ion propulsion; and you also write of the vast improvements in material science that will enable (we hope) a space elevator. But I think it’s also important to remember that those same material science improvements also increase the net efficiency of rockets as well.

    With today’s material science, a rocket equivalent to a Saturn V should be lighter and stronger. The electronics and instruments equivalent to those in the Saturn V and the Command Module should be (as you indicate) roughly the size of a small cell phone (not counting sensors, actuators, antennae, etc.). Good grief, the first generation shuttle computers still used magnetic core memory! A bit had a measurable mass!

    And the machining! When the shuttle was in design, I recall the popular science magazines making a huge fuss about the tiles. These were so complex, they couldn’t be mass produced to spec. Each individual tile had to be individually designed… on a COMPUTER! Back in 1974, that was truly awe inspiring. Today, almost anyone reading your article has a better computer than the best available then, and many have better CAD software.

    And then there’s engineering competence. Not to take anything from the Apollo engineers; but as a society, we’ve advanced. In Tom Kelly’s book on the Lunar Lander, he tells of how NASA came in to try to save the Lander’s troubled schedule; and they schooled Grumman in advanced engineering techniques — like Gantt Charts. Those techniques, and a lot more developed since, are far more wide spread and standard across all facets of our society today.

    And then there’s the plain knowledge that we’ve done this before, and the expertise in launch operations, and the science that we’ve discovered since Apollo. A lot of open questions then are settled science now.

    None of this makes rockets a good long-term answer for low-cost space travel. The economics of throwing away 94% of your vessel are still lousy. But just as with your cell phone example… If NASA in 1962 had had access to the computers, materials, machining, fuel, and work force of today, they could’ve gotten to the Moon by mid-decade, probably. They had drive and budget aplenty, and made the most of what they had; if they’d had more, no doubt they’d’ve done more. Almost everything would’ve been done better, sooner, for less money. The only thing that couldn’t be compressed would be training time and time in actual missions as the crews learned to go to the Moon.

    If NASA today can’t get rockets and even long-term bases to the Moon in a few years, it’s not for technological reasons. The budget’s not there, and the will’s not there.

  8. JohnMc says:

    You wrote a fine article but you could have done without the attitude — “The key to any organization’s ultimate success, from NASA to any private enterprise, is that there are leaders at the top with vision. NASA’s mistakes were not that it was built by the government, but that the leaders placed the wrong bets. Microsoft, by contrast, succeeded because Bill Gates made many smart bets. NASA’s current goal is “flags and footprints”, but their goal should be to make it cheap to do those things, a completely different objective.”

    How many bad Microsoft bets do you want me to list? Not catching on to the internet till it was almost too late. Not talking to Xerox when they should have during the Apple-Microsoft suit. Not being so paranoid about open source. Those are just to name a few. Microsoft’s success has to do with two things — 1) Intel/AMD being able to track Moore’s law quite well. 2) Microsoft’s willingness to commit to continuous improvement. It has had very little to do with vision or leadership I am afraid.

    As to that being applicable to NASA. Well its an apple’s and oranges thing. Microsoft was blessed with Intel who was able to deliver 2-5x the processing power every 18months. So regardless of how bad Microsoft’s code was it worked on the faster processor. NASA on the other hand was constrained and still is by one simple rule — mass velocity of the propellant. Unlike Intel there is no chemical company out there designing 2x better propellants every two years or ever will be. You should also be frank with your readers, ion propulsion does not work in an atmosphere very well if at all.

    I will grant that the space elevator is the way to go for long term sustainable lift capability. But again I have to be relative. The whole science of nanotech is barely 15 years old. NASA has been around since the late 50’s. So for a sizable period of NASA’s history the tech was just not there to even consider space elevators as a viable engineering problem till recently.

    Nor do I think the vision many see depicted for space elevators is what may ultimately be used. Most depictions show a ribbon of equal size and I presume mass the length of the Earth to the orbiting retaining mass. Talk to anyone who builds radio towers. 2/3rds of the mass of the structure is in the first 1/2 height of the tower, its mass shrinking as it rises. The only reason that SE’s are depicted as they are is the presumption that they trolley follows the full length of the ribbon. Pure folly.

    You almost got it with your speed comment for the trolley’s. The ribbon would have variable architecture from base to a release point. The trolley would be so designed that the ‘wheels’ (or possibly maglev) follow the variable curvature of the ribbon shrinking as the trolley rises. Nor does the trolley have to ride the ribbon beyond release point. The trolley accelerates to escape velocity as you suggest then releases from the ribbon to take alternate paths or just coast along the ribbon using same for corrective inputs.

    But it is an interesting article none the less.
    From Keith: My “attitude” was meant to be humorous. I agree that Microsoft has made many mistakes and the rest of the book discusses many of them.

  9. John Hunt says:

    Re: the space elevator, I’m a skeptic. First, we’ve got to get many miles long nanotubes produced without defects. Next there’s the small matter of moving an asteroid or something into the right place. Then there’s the problem of one little, teeny, tiny bit of space junk hitting the cable and the liability if it all comes crashing down.

    Rockets, however are real. Many countries and companies produce them and they seem to be on the verge of getting significantly cheaper. Mine lunar ice for use as fuel in LEO, mining lunar regolith for metals and you expand the existing and emerging markets for large GEO satellites, Solar Power Satellites, and LEO hotels.

    Space elevators may come some day but not before the whole cis-lunar market is developed thanks to good old fashion rockets.

    From Keith: Rockets are not getting much cheaper and they will never be close to as cheap as a space elevator. Brad Edwards’ book responds to all the points you make.

  10. Dougger says:

    You only touch on the space debris issue to merely suggest that the first elevator will need to maneuver to avoid conflict.
    What about the terrestrial hazards?
    What happens to the ribbon and its climbers when the ribbon is severed at the ground?
    Or worse, at low-span by a aircraft collision?
    Or at mid-span by another spacecraft?
    Will there be enough maneuverability at the top to clear the mid-span of an approaching hazard?
    How about a missile strike?
    When an accident or an attack happens, at any part of the ribbon, where will the pieces go or fall?

    From Keith: Brad Edwards’ book goes into a lot of detail on this.

  11. dave benefield says:

    I worked at Kennedy/Cape Canaveral as an engineer for 7 years, and specifically on elevators for a good portion of that. It has always seemed logical to me that someday the idea of a space elevator would come to fruition. The first vertical trip the astronauts always take is on an elevator. That’s also the first thing NASA insists be repaired after the launch. They are the workhorses of the Space Program that get no glory.


  12. grs says:

    Space elevator advocates usually give short shrift to the biggest problem facing the concept–collision with other orbiting objects–and this article is no exception. It’s easy to say that the elevator will dodge other objects, but the question is whether this will be so simple to do in practice. All orbiting spacecraft and debris either follow an equatorial orbit or cross the equator. A space elevator will therefore cross the paths of all orbiting objects; it’s unavoidable. I’m skeptical that an object of this size will be flexible enough to be able to move out of the way of even one object, let alone multiple orbiting objects at various altitudes, having various orbital periods, day in and day out. Until this problem is worked out in detail, rather than glossed over, the space elevator will remain a daydream.

    From Keith: This is one of the interesting problems to work out, no more and no less.

  13. jimmy chacko says:

    As a lay person with an interest in space it seems like I’ve been reading about this idea and carbon nanotubes for the entire decade. So I disagree that no one it discussing it seriously. However you’re right about NASA, fixated on the past glory and the politics and it guarantees nothing will get done. We need the economy to improve a we’ll see venture capitalists making taking some risks.

  14. Brock says:

    I don’t think the Space Elevator is a feasible concept. The necessary specific strength of the elevator is very nearly the specific strength of individual carbon nanotubes. Do you know any systems where the macro is just as strong as the nano parts that make it up? I don’t. We would need nanotech perfection, and no wear and tear, all the way from the surface to the top. I just don’t see it as a feasible engineering project.

    See the link in my name for details on that.

    I think we’re stuck with rockets for now. They can be fairly cheap — its NASA’s management practices that are expensive. Google “Sea Dragon Rocket” for an idea about how cheap they can be. Later we may develop fusion, and Skyhooks and the Space Pier seems to be within the limits of materials science.

    From Keith: I agree we need a way to repair the ribbon. Once you build something, then you figure out how to repair it. But figuring out today is premature, like asking a Viking how to repair a fiberglass boat.

  15. Doug Collins says:

    The comment about the elevator having more of its mass near the earth and tapering to a thinner ribbon as it gets higher, like a radio tower, makes me wonder if people are clear on the way it is suposed to work. It is “hung’ from an orbiting satelite ( and an equivalent mass is paid out on the other side of the satelite, away from the earth so the center of mass stays constant).

  16. Doug Collins says:

    Another solution to the debris problem would be to use multiple ribbons with significant redundancy and possibly, even a self repair capability.

  17. Joseph Somsel says:

    This $10 a pound number seems fishy to me.

    It might represent the marginal cost of moving a pound — probably the electrical energy needed (at 25 cents a kilowatt then 40 kW which sounds about right).

    However, there will be operations and maintenance costs, TBD.

    Worst will be interest of capital and amortization.

    Say it has an overnight cost of $100 billion. At 10% cost of capital, that means you have a fixed cost every year of $10 billion. If you move a million pounds a year, you need to charge $10,000 a pound JUST for interest and interest only.

    Move a BILLION lbs a year, and then you get to $100 a lb for interest.

    Is there any expectation of THAT kind of PAYING market?

    Of course, $100 billion is probably low first cost.

    From Keith: Brad Edwards’ book has a lot more detailed financial numbers. I also think that $10B / year in interest is bizarre. You can’t pay for things like highways with that sort of thinking.

  18. Space junk can create problem for earth„there is a loss of space junk over there„„

  19. ech says:

    While engineering may be fungible, science is not. Apollo was fundamentally an engineering problem. Most of the key technologies were already developed and ready to go. In the case of carbon nanotubes, how is NASA supposed to develop them? You can’t take a Shuttle propulsion engineer and ask them to do cutting edge materials science research. Like it or not, there are only a finite supply of scientists and research labs that have the skills and equipment to do the basic research needed on carbon nanotubes . It will take a decade or more to turn them from the lab products that they are into a well-understood commercial product capable of being used in an elevator. I wish it wasn’t true but it is. At least that is what a prominent researcher in the field has told me.

    You dismiss Brooks’ Law, but it still applies — adding people to a late project can make it later.
    From Keith: Okay, so you are admitting that everything but the nanotubes is fungible? Then, let’s get that all going and then create a Manhattan Project for the nanotubes. In fact, even a lot about the nanotubes is doable today, such as designing the ribbon weave structure. There is a lot of software and such for analyzing nanotubes. In fact, the creation of the nanotubes is not even necessarily pure science, as it is mostly a manufacturing process! So what you think of as science and engineering isn’t so clear-cut.

  20. jasony says:

    Every time I read that Kennedy speech I get a lump in my throat. While I believe the image of Aldrin on the moon will stand forever as a pinnacle of civilization (sadly), I think Kennedy’s call to DO the thing is every bit as inspiring. If only we had leader among us who were able to challenge us with difficulty, not lull us with compassion and concern.

    People accomplish more when they are challenged than they do when they’re coddled.

    Great article.

  21. We’ve yet to make the jump to space elevators, but i don’t think it’s too far out of the picture :P

  22. Jeremy Ramsden says:

    This is a very interesting post with a lot to think about. A real comment will need time to digest what I’ve read. But an immediate thought is — please don’t suggest that Microsoft should serve as an example to NASA of how to do things! Agreed that the space shuttle and many of the current and planned programs are flawed, but the Apollo moon landings were a great success and truly inspirational. In contrast, Microsoft’s products seem to be perpetually stuck at the beta stage and cause constant irritation whenever used because of their numerous defects and primitive conception. I find it amazing that they have managed to push themselves into such a dominant position — globally, we are experiencing colossal inefficiencies in productivity due to the widespread use of Microsoft products. This is not the kind of “success” we need to drive something like the space elevator.

    From Keith: My point was in how MS stayed at the top of the computer industry for so long, because it got into the PC market, invested in graphical user interfaces, 32-bit computing, reinvented itself for the Internet, invested in developer tools, office productivity, etc. The computer industry graveyard is filled with Microsoft’s erstwhile competitors. The point is that Bill Gates make smart and strategic bets. That their codebases are old and creeky is different. I do agree how people confuse them today so I will consider revisiting this.

  23. Using today’s materials, we can already build rotating tethers to take a package from an airplane to orbit. Rotating tethers provide a similar solution as the space elevator without all of the up-front cost and materials science breakthrough requirements. They have also solved the debris collision problem. Why hasn’t a boost tether been built already? This is not a billion-dollar development project. Why don’t space elevator advocates ever mention rotating tethers?

    For a detailed description, see
    a movie showing how it works:
    the airplane to orbit concept:
    and be sure to check out the other papers and animations on

    From Keith: I would prefer to ask for a space elevator, and when we have their attention mention we can use tethers in the meanwhile. Space elevators are more structurally sound. We can create a big base at the top. It is a good idea, I should put some words in there. I didn’t only because I haven’t read enough materials on the topic yet to feel comfortable. Thanks for the tips.

  24. Samantha Atkins says:

    The Space Elevator is the wrong technology. We are off by an order of magnitude in proper strength materials for this project even in very small amounts much less in the quantities required. Our crawlers are much too slow to date. The project is quite expensive. There are easier ways to cut two orders of magnitude off our launch costs.

    From Keith: The nanotube manufacturing problem is significant and needs to be solved. But unlike so much of biotech research, the nanotube design is understood and simple. The crawlers can go at any speed, it is just a matter of power and friction and other stuff well-understood. There are many estimates of around $10B for the space elevator. The Apollo Project using today’s dollars was $170B.

  25. robert moench says:

    The first question that came to mind when I saw something on Discovery, was a pragmatic one. Who would control the location on Earth of a Space Elevator? 2nd Would it not be necessary to at times ‘reel it in’? 3rd There is an ongoing search for ways to protect Space Craft from Solar radiation. Lead has been ruled out as too heavy. Would a S.E. solve that issue?

  26. Interesting. Is it really feasible? This will be expensive and very hard to do. It will also take a long time to do this thing. this will be done in many years and probably I’m dead that time. :)

  27. 47LD520 says:

    Awesome! Does anyone else feel like watching Space Odyssey 2001 after reading that? :P Though on a different note, I know progression like this is important for the Earth as a whole, but I think there are still many problems back on the planet that still need to be fixed before wasting so much money on such a thing as this. That’s just my opinion though…

  28. patchaiappan says:

    yah from 2 years am knowing about this space elevator system but i have one dought is there any emergency switch provided inside the elevator or not.….….…?

  29. Really interesting information. I read about it some times ago.

  30. No one knew. Still, a feeling in the gut told us that this was the greatest moment in the history of life. We were leaving the planet. Our feet had stirred the dust of an alien world.”

    Awesome Stuff!