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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 DrudgeReport.com 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.

Why?

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 Instapundit.com, 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.

An obvious next step in the effort to dramatically lower the cost of access to low Earth orbit is to explore non-rocket options. A wide variety of ideas have been proposed, but it’s difficult to meaningfully compare them and to get a sense of what’s actually on the technology horizon. The best way to quantitatively assess these technologies is by using Technology Readiness Levels (TRLs). TRLs are used by NASA, the United States military, and many other agencies and companies worldwide. Typically there are nine levels, ranging from speculations on basic principles to full flight-tested status.

The system NASA uses can be summed up as follows:

TRL 1 Basic principles observed and reported
TRL 2 Technology concept and/or application formulated
TRL 3 Analytical and experimental critical function and/or characteristic proof-of concept
TRL 4 Component and/or breadboard validation in laboratory environment
TRL 5 Component and/or breadboard validation in relevant environment
TRL 6 System/subsystem model or prototype demonstration in a relevant environment (ground or space)
TRL 7 System prototype demonstration in a space environment
TRL 8 Actual system completed and “flight qualified” through test and demonstration (ground or space)
TRL 9 Actual system “flight proven” through successful mission operations.

Progress towards achieving a non-rocket space launch will be facilitated by popular understanding of each of these proposed technologies and their readiness level. This can serve to coordinate more work into those methods that are the most promising. I think it is important to distinguish between options with acceleration levels within the range human safety and those that would be useful only for cargo. Below I have listed some non-rocket space launch methods and my assessment of their technology readiness levels.

Spacegun: 6. The US Navy’s HARP Project launched a projectile to 180 km. With some level of rocket-powered assistance in reaching stable orbit, this method may be feasible for shipments of certain forms of freight.

Spaceplane: 6. Though a spaceplane prototype has been flown, this is not equivalent to an orbital flight. A spaceplane will need significantly more delta-v to reach orbit than a suborbital trajectory requires.

Orbital airship: 2. Though many subsystems have been flown, the problem of atmospheric drag on a full scale orbital airship appears to prevent this kind of architecture from reaching space.

Space Elevator: 3. The concept may be possible, albeit with major technological hurdles at the present time. A counterweight, such as an asteroid, needs to be positioned above geostationary orbit. The material of the elevator cable needs to have a very high tensile strength/mass ratio; no satisfactory material currently exists for this application. The problem of orbital collisions with the elevator has also not been resolved.

Electromagnetic catapult: 4. This structure could be built up the slope of a tall mountain to avoid much of the Earth’s atmosphere. Assuming a small amount of rocket power would be used after a vehicle exits the catapult, no insurmountable technological obstacles stand in the way of this method. The sheer scale of the project makes it difficult to develop the technology past level 4.

Are there any ideas we’re missing here?

It is interesting to note that the technical possibility to send interstellar Ark appeared in 1960th, and is based on the concept of “Blust-ship” of Ulam. This blast-ship uses the energy of nuclear explosions to move forward. Detailed calculations were carried out under the project “Orion”. http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) In 1968 Dyson published an article “Interstellar Transport”, which shows the upper and lower bounds of the projects. In conservative (ie not imply any technical achievements) valuation it would cost 1 U.S. GDP (600 billion U.S. dollars at the time of writing) to launch the spaceship with mass of 40 million tonnes (of which 5 million tons of payload), and its time of flight to Alpha Centauri would be 1200 years. In a more advanced version the price is 0.1 U.S. GDP, the flight time is 120 years and starting weight 150 000 tons (of which 50 000 tons of payload). In principle, using a two-tier scheme, more advanced thermonuclear bombs and reflectors the flying time to the nearest star can reduce to 40 years.
Of course, the crew of the spaceship is doomed to extinction if they do not find a habitable and fit for human planet in the nearest star system. Another option is that it will colonize uninhabited planet. In 1980, R. Freitas proposed a lunar exploration using self-replicating factory, the original weight of 100 tons, but to control that requires artificial intelligence. “Advanced Automation for Space Missions” http://www.islandone.org/MMSG/aasm/ Artificial intelligence yet not exist, but the management of such a factory could be implemented by people. The main question is how much technology and equipment should be enough to throw at the moonlike uninhabited planet, so that people could build on it completely self-sustaining and growing civilization. It is about creating something like inhabited von Neumann probe. Modern self-sustaining state includes at least a few million people (like Israel), with hundreds of tons of equipment on each person, mainly in the form of houses, roads. Weight of machines is much smaller. This gives us the upper boundary of the able to replicate human colony in the 1 billion tons. The lower estimate is that there would be about 100 people, each of which accounts for approximately 100 tons (mainly food and shelter), ie 10 000 tons of mass. A realistic assessment should be somewhere in between, and probably in the tens of millions of tons. All this under the assumption that no miraculous nanotechnology is not yet open.
The advantage of a spaceship as Ark is that it is non-specific reaction to a host of different threats with indeterminate probabilities. If you have some specific threat (the asteroid, the epidemic), then there is better to spend money on its removal.
Thus, if such a decision in the 1960th years were taken, now such a ship could be on the road.
But if we ignore the technical side of the issue, there are several trade-offs on strategies for creating such a spaceship.
1. The sooner such a project is started, the lesser technically advanced it would be, the lesser would be its chances of success and higher would be cost. But if it will be initiated later, the greater would be chances that it will not be complete until global catastrophe.
2. The later the project starts, the greater are the chance that it will take “diseases” of mother civilization with it (e.g. ability to create dangerous viruses ).
3. The project to create a spaceship could lead to the development of technologies that threaten civilization itself. Blast-ship used as fuel hundreds of thousands of hydrogen bombs. Therefore, it can either be used as a weapon, or other party may be afraid of it and respond. In addition, the spaceship can turn around and hit the Earth, as star-hammer — or there maybe fear of it. During construction of the spaceship could happen man-made accidents with enormous consequences, equal as maximum to detonation of all bombs on board. If the project is implementing by one of the countries in time of war, other countries could try to shoot down the spaceship when it launched.
4. The spaceship is a means of protection against Doomsday machine as strategic response in Khan style. Therefore, the creators of such a Doomsday machine can perceive the Ark as a threat to their power.
5. Should we implement a more expensive project, or a few cheaper projects?
6. Is it sufficient to limit the colonization to the Moon, Mars, Jupiter’s moons or objects in the Kuiper belt? At least it can be fallback position at which you can check the technology of autonomous colonies.
7. The sooner the spaceship starts, the less we know about exoplanets. How far and how fast the Ark should fly in order to be in relative safety?
8. Could the spaceship hide itself so that the Earth did not know where it is, and should it do that? Should the spaceship communicate with Earth? Or there is a risk of attack of a hostile AI in this case?
9. Would not the creation of such projects exacerbate the arms race or lead to premature depletion of resources and other undesirable outcomes? Creating of pure hydrogen bombs would simplify the creation of such a spaceship, or at least reduce its costs. But at the same time it would increase global risks, because nuclear non-proliferation will suffer complete failure.
10. Will the Earth in the future compete with its independent colonies or will this lead to Star Wars?
11. If the ship goes off slowly enough, is it possible to destroy it from Earth, by self-propelling missile or with radiation beam?
12. Is this mission a real chance for survival of the mankind? Flown away are likely to be killed, because the chance of success of the mission is no more than 10 per cent. Remaining on the Earth may start to behave more risky, in logic: “Well, if we have protection against global risks, now we can start risky experiments.” As a result of the project total probability of survival decreases.
13. What are the chances that its computer network of the Ark will download the virus, if it will communicate with Earth? And if not, it will reduce the chances of success. It is possible competition for nearby stars, and faster machines would win it. Eventually there are not many nearby stars at distance of about 5 light years — Alpha Centauri, the Barnard star, and the competition can begin for them. It is also possible the existence of dark lonely planets or large asteroids without host-stars. Their density in the surrounding space should be 10 times greater than the density of stars, but to find them is extremely difficult. Also if nearest stars have not any planets or moons it would be a problem. Some stars, including Barnard, are inclined to extreme stellar flares, which could kill the expedition.
14. The spaceship will not protect people from hostile AI that finds a way to catch up. Also in case of war starships may be prestigious, and easily vulnerable targets — unmanned rocket will always be faster than a spaceship. If arks are sent to several nearby stars, it does not ensure their secrecy, as the destination will be known in advance. Phase transition of the vacuum, the explosion of the Sun or Jupiter or other extreme event can also destroy the spaceship. See e.g. A.Bolonkin “Artificial Explosion of Sun. AB-Criterion for Solar Detonation” http://www.scribd.com/doc/24541542/Artificial-Explosion-of-S…Detonation
15. However, the spaceship is too expensive protection from many other risks that do not require such far removal. People could hide from almost any pandemic in the well-isolated islands in the ocean. People can hide on the Moon from gray goo, collision with asteroid, supervolcano, irreversible global warming. The ark-spaceship will carry with it problems of genetic degradation, propensity for violence and self-destruction, as well as problems associated with limited human outlook and cognitive biases. Spaceship would only burden the problem of resource depletion, as well as of wars and of the arms race. Thus, the set of global risks from which the spaceship is the best protection, is quite narrow.
16. And most importantly: does it make sense now to begin this project? Anyway, there is no time to finish it before become real new risks and new ways to create spaceships using nanotech.
Of course it easy to envision nano and AI based Ark – it would be small as grain of sand, carry only one human egg or even DNA information, and could self-replicate. The main problem with it is that it could be created only ARTER the most dangerous period of human existence, which is the period just before Singularity.

For any assembly or structure, whether an isolated bunker or a self sustaining space colony, to be able to function perpetually, the ability to manufacture any of the parts necessary to maintain, or expand, the structure is an obvious necessity. Conventional metal working techniques, consisting of forming, cutting, casting or welding present extreme difficulties in size and complexity that would be difficult to integrate into a self sustaining structure.

Forming requires heavy high powered machinery to press metals into their final desired shapes. Cutting procedures, such as milling and lathing, also require large, heavy, complex machinery, but also waste tremendous amounts of material as large bulk shapes are cut away emerging the final part. Casting metal parts requires a complex mold construction and preparation procedures, not only does a negative mold of the final part need to be constructed, but the mold needs to be prepared, usually by coating in ceramic slurries, before the molten metal is applied. Unless thousands of parts are required, the molds are a waste of energy, resources, and effort. Joining is a flexible process, and usually achieved by welding or brazing and works by melting metal between two fixed parts in order to join them — but the fixed parts present the same manufacturing problems.

Ideally then, in any self sustaining structure, metal parts should be constructed only in the final desired shape but without the need of a mold and very limited need for cutting or joining. In a salient progressive step toward this necessary goal, NASA demonstrates the innovative Electron Beam Free Forming Fabrication (http://www.aeronautics.nasa.gov/electron_beam.htm) Process. A rapid metal fabrication process essentially it “prints” a complex three dimensional object by feeding a molten wire through a computer controlled gun, building the part, layer by layer, and adding metal only where you desire it. It requires no molds and little or no tooling, and material properties are similar to other forming techniques. The complexity of the part is limited only by the imagination of the programmer and the dexterity of the wire feed and heating device.

Electron beam freeform fabrication process in action
Electron beam freeform fabrication process in action

According to NASA materials research engineer Karen Taminger, who is involved in developing the EBF3 process, extensive simulations and modeling by NASA of long duration space flights found no discernable pattern to the types of parts which failed, but the mass of the failed parts remained remarkably consistent throughout the studies done. This is a favorable finding to in-situe parts manufacturing and because of this the EBF³ team at NASA has been developing a desktop version. Taminger writes:

“Electron beam freeform fabrication (EBF³) is a cross-cutting technology for producing structural metal parts…The promise of this technology extends far beyond its applicability to low-cost manufacturing and aircraft structural designs. EBF³ could provide a way for astronauts to fabricate structural spare parts and new tools aboard the International Space Station or on the surface of the moon or Mars”

NASA’s Langley group working on the EBF3 process took their prototype desktop model for a ride on the microgravity simulating NASA flight and found the process works just fine even in micro gravity, or even against gravity.

A structural metal part fabricated from EBF³
A structural metal part fabricated from EBF³

The advantages this system offers are significant. Near net shape parts can be manufactured, significantly reducing scrap parts. Unitized parts can be made — instead of multiple parts that need riveting or bolting, final complex integral structures can be made. An entire spacecraft frame could be ‘printed’ in one sitting. The process also creates minimal waste products and is highly energy and feed stock efficient, critical to self sustaining structures. Metals can be placed only where they are desired and the material and chemistry properties can be tailored through the structure. The technical seminar features a structure with a smooth transitional gradient from one alloy to another. Also, structures can be designed specifically for their intended purposes, without needing to be tailored to manufacturing process, for example, stiffening ridges can be curvilinear, in response to the applied forces, instead of typical grid patterns which facilitate easy conventional manufacturing techniques. Manufactures, such as Sciaky Inc, (http://www.sciaky.com/64.html) are all ready jumping on the process

In combination with similar 3D part ‘printing’ innovations in plastics and other materials, the required complexity for sustaining all the mechanical and structural components of a self sustaining structure is plummeting drastically. Isolated structures could survive on a feed stock of scrap that is perpetually recycled as worn parts are replaced by free form manufacturing and the old ones melted to make new feed stock. Space colonies could combine such manufacturing technologies and scrap feedstock with resource collection creating a viable minimal volume and energy consuming system that could perpetually repair the structure – or even build more. Technologies like these show that the atomic level control that nanotechnology manufacturing proposals offer are not necessary to create self sustaining structure, and that with minor developments of modern technology, self sustaining structures could be built and operated successfully.

Many years ago, in December 1993 to be approximate, I noticed a space-related poster on the wall of Eric Klien’s office in the headquarters of the Atlantis Project. We chatted for a bit about the possibilities for colonies in space. Later, Eric mentioned that this conversation was one of the formative moments in his conception of the Lifeboat Foundation.

Another friend, filmmaker Meg McLain has noticed that orbital hotels and space cruise liners are all vapor ware. Indeed, we’ve had few better depictions of realistic “how it would feel” space resorts since 1968’s Kubrick classic “2001: A Space Odyssey.” Remember the Pan Am flight to orbit, the huge hotel and mall complex, and the transfer to a lunar shuttle? To this day I know people who bought reservation certificates for whenever Pan Am would begin to fly to the Moon.

In 2004, after the X Prize victory, Richard Branson announced that Virgin Galactic would be flying tourists by 2007. So far, none.

A little later, Bigelow announced a fifty million dollar prize if only tourists could be launched to orbit by January 2010. I expect the prize money won’t be claimed in time.

Why? Could it be that the government is standing in the way? And if tourism in space can’t be “permitted” what of a lifeboat colony?

Meg has set out to make a documentary film about how the human race has arrived four decades after the Moon landing and still no tourist stuff. Two decades after Kitty Hawk, a person could fly across the country; three decades, across any ocean.

Where are the missing resorts?

Here is the link to her film project:
http://www.freewebs.com/11at40/

(Crossposted on the blog of Starship Reckless)

Eleven years ago, Random House published my book To Seek Out New Life: The Biology of Star Trek. With the occasion of the premiere of the Star Trek reboot film and with my mind still bruised from the turgid awfulness of Battlestar Galactica, I decided to post the epilogue of my book, very lightly updated — as an antidote to blasé pseudo-sophistication and a reminder that Prometheus is humanity’s best embodiment. My major hope for the new film is that Uhura does more than answer phones and/or smooch Kirk.

Coda: The Infinite Frontier

star-trekA younger science than physics, biology is more linear and less exotic than its older sibling. Whereas physics is (mostly) elegant and symmetric, biology is lunging and ungainly, bound to the material and macroscopic. Its predictions are more specific, its theories less sweeping. And yet, in the end, the exploration of life is the frontier that matters the most. Life gives meaning to all elegant theories and contraptions, life is where the worlds of cosmology and ethics intersect.

Our exploration of Star Trek biology has taken us through wide and distant fields — from the underpinnings of life to the purposeful chaos of our brains; from the precise minuets of our genes to the tangled webs of our societies.

How much of the Star Trek biology is feasible? I have to say that human immortality, psionic powers, the transporter and the universal translator are unlikely, if not impossible. On the other hand, I do envision human genetic engineering and cloning, organ and limb regeneration, intelligent robots and immersive virtual reality — quite possibly in the near future.

Furthermore, the limitations I’ve discussed in this book only apply to earth biology. Even within the confines of our own planet, isolated ecosystems have yielded extraordinary lifeforms — the marsupials of Australia; the flower-like tubeworms near the hot vents of the ocean depths; the bacteriophage particles which are uncannily similar to the planetary landers. It is certain that when we finally go into space, whatever we meet will exceed our wildest imaginings.

Going beyond strictly scientific matters, I think that the accuracy of scientific details in Star Trek is almost irrelevant. Of course, it puzzles me that a show which pays millions to principal actors and for special effects cannot hire a few grad students to vet their scripts for glaring factual errors (I bet they could even get them for free, they’d be that thrilled to participate). Nevertheless, much more vital is Star Trek’s stance toward science and the correctness of the scientific principles that it showcases. On the latter two counts, the series has been spectacularly successful and damaging at the same time.

The most crucial positive elements of Star Trek are its overall favorable attitude towards science and its strong endorsement of the idea of exploration. Equally important (despite frequent lapses) is the fact that the Enterprise is meant to be a large equivalent to Cousteau’s Calypso, not a space Stealth Bomber. However, some negative elements are so strong that they almost short-circuit the bright promise of the show.

I cannot be too harsh on Star Trek, because it’s science fiction — and TV science fiction, at that. Yet by choosing to highlight science, Star Trek has also taken on the responsibility of portraying scientific concepts and approaches accurately. Each time Star Trek mangles an important scientific concept (such as evolution or black hole event horizons), it misleads a disproportionately large number of people.

The other trouble with Star Trek is its reluctance to showcase truly imaginative or controversial ideas and viewpoints. Of course, the accepted wisdom of media executives who increasingly rely on repeating well-worn concepts is that controversial positions sink ratings. So Star Trek often ignores the agonies and ecstasies of real science and the excitement of true or projected scientific discoveries, replacing them with pseudo-scientific gobbledygook more appropriate for series like The X-Files, Star Wars and Battlestar Galactica. Exciting ideas (silicon lifeforms beyond robots, parallel universes) briefly appear on Star Trek, only to sink without a trace. This almost pathological timidity of Star Trek, which enjoys the good fortune of a dedicated following and so could easily afford to cut loose, does not bode well for its descendants or its genre.

trekmovie2w

On the other hand, technobabble and all, Star Trek fulfills a very imporant role. It shows and endorses the value of science and technology — the only popular TV series to do so, at a time when science has lost both appeal and prestige. With the increasing depth of each scientific field, and the burgeoning of specialized jargon, it is distressingly easy for us scientists to isolate ourselves within our small niches and forget to share the wonders of our discoveries with our fellow passengers on the starship Earth. Despite its errors, Star Trek’s greatest contribution is that it has made us dream of possibilities, and that it has made that dream accessible to people both inside and outside science.

Scientific understanding does not strip away the mystery and grandeur of the universe; the intricate patterns only become lovelier as more and more of them appear and come into focus. The sense of excitement and fulfillment that accompanies even the smallest scientific discovery is so great that it can only be communicated in embarrassingly emotional terms, even by Mr. Spock and Commander Data. In the end these glimpses of the whole, not fame or riches, are the real reason why the scientists never go into the suspended animation cocoons, but stay at the starship chart tables and observation posts, watching the great galaxy wheels slowly turn, the stars ignite and darken.

Star Trek’s greatest legacy is the communication of the urge to explore, to comprehend, with its accompanying excitement and wonder. Whatever else we find out there, beyond the shelter of our atmosphere, we may discover that thirst for knowledge may be the one characteristic common to any intelligent life we encounter in our travels. It is with the hope of such an encounter that people throng around the transmissions from Voyager, Sojourner, CoRoT, Kepler. And even now, contained in the sphere of expanding radio and television transmissions speeding away from Earth, Star Trek may be acting as our ambassador.

May 2: Many U.S. emergency rooms and hospitals crammed with people… ”Walking well” flood hospitals… Clinics double their traffic in major cities … ER rooms turn away EMT cases. — CNN

Update May 4: Confirmed cases of H1N1 virus now at 985 in 20 countries (Mexico: 590, 25 deaths) — WHO. In U.S.: 245 confirmed U.S. cases in 35 states. — CDC.

“We might be entering an Age of Pandemics… a broad array of dangerous emerging 21st-century diseases, man-made or natural, brand-new or old, newly resistant to our current vaccines and antiviral drugs…. Martin Rees bet $1,000 that bioterror or bioerror would unleash a catastrophic event claiming one million lives in the next two decades…. Why? Less forest, more contact with animals… more meat eating (Africans last year consumed nearly 700 million wild animals… numbers of chickens raised for food in China have increased 1,000-fold over the past few decades)… farmers cut down jungle, creating deforested areas that once served as barriers to the zoonotic viruses…” — Larry Brilliant, Wall Street Journal


On Wednesday, May 9th 2001, over twenty military, intelligence, government, corporate and scientific witnesses came forward at the National Press Club in Washington, DC to establish the reality of UFOs or extraterrestrial vehicles, extraterrestrial life forms, and resulting advanced energy and propulsion technologies.

DEAFENING SILENCE: Media Response to the May 9th Event
and its Implications Regarding the Truth of Disclosure

by Jonathan Kolber

http://www.disclosureproject.org/May9response.htm

My intent is to establish that the media’s curiously limited coverage of the May 9, 2001 National Press Club briefing is highly significant.

At that event, nearly two dozen witnesses stepped forward and offered their testimony as to personal knowledge of ET’s and ET-related technologies. These witnesses claimed top secret clearances and military and civilian accomplishments of the highest order. Some brandished uncensored secret documents. The world’s major media were in attendance, yet few reported what they saw, most neglecting to even make skeptical mention.

How can this be? Major legal trials are decided based on weaker testimony than was provided that day. Prison sentences are meted out on less. The initial Watergate evidence was less, and the implications of this make Watergate insignificant by comparison. Yet the silence is deafening.

Three Possibilities:

If true, the witness testimony literally ushers in the basis for a whole new world of peace and prosperity for all. Validating the truth of Disclosure is probably the most pressing question of our times. The implications for the human future are so overwhelming that virtually everything else becomes secondary. However, the mass media have not performed validation. No investigative stories seeking to prove or disprove the witness testimony have appeared.

This cannot be due to lack of material; in the remainder of this article I will perform validation based upon material handed to the world’s media on May 9th.

In my view, only three possibilities exist: the witnesses were all lying, they were all delusional, or they were documenting the greatest cover-up in history. The reason is that if any one witness were neither lying nor delusional, then the truth of Disclosure is established. Let’s examine each possibility in turn.

If the witnesses were lying, a reasonable observer would ask, “where is the payoff?” What is the possible benefit to a liar pleading for the chance to testify before Congress under oath? The most likely payoff would be a trip to jail. These witnesses have not openly requested any financial compensation, speaking engagements or the like, and the Disclosure Project’s operation cannot support a payoff to dozens of persons. A cursory evaluation of its “products” coupled with a visit to its Charlottesville offices will establish this. Further, the parent organization, CSETI, is an IRS 501C3 nonprofit organization, and its lack of financial resources is a matter of public record. So the notion that the witnesses were doing so for material benefit is unsupported by facts at hand.

To my knowledge, large numbers of persons do not collude to lie without some compelling expected benefit. Other than money, the only such reason I can conceive in this case would be ideology. I wonder what radical extremist “ideology” could plausibly unite such a diverse group of senior corporate and military witnesses, nearly all of whom have previously displayed consistent loyalty to the United States in word and deed? I find none, and I therefore dismiss lying as implausible.

Further, the witnesses claimed impressive credentials. Among them were a Brigadier General, an Admiral, men who previously had their finger on the nuclear launch trigger, air traffic controllers, Vice Presidents of major American corporations—persons who either routinely have had our lives in their hands or made decisions affecting everyone. To my knowledge, in the half-year since May 9th, not a single claimed credential has been challenged in a public forum. Were they lying en masse, such an exposure would be a nice feather in the cap of some reporter. However, it hasn’t happened.

If all the witnesses were delusional, then a reasonable observer would presume that such “mass psychosis” did not suddenly manifest. That is, a number of witnesses would have shown psychotic tendencies in the past, in some cases probably including hospitalization. To my knowledge, this has not been alleged.

If they were documenting the greatest cover-up in history, and especially as briefing books that enumerated details of specific cases were handed out on May 9th to the dozens of reporters present, coverage should have dominated the media ever since, with a national outcry for hearings. This did not happen either.

Implications:

What do the above facts and inferences imply about the state of affairs in the media and the credibility of the witness testimony? In my view, they imply a lot.

If the witnesses were neither lying nor delusional, then the deafening media silence following May 9th implies an intentional process of failure to explore and reveal the truth. Said less politely, it implies censorship. (If I am right, this is itself an explosive statement, worthy of significant media attention—which it will not receive.) The only stories comparable in significance to May 9th would be World War III, a plague decimating millions, or the like. Yet between May 9th and September 11th, the news media was saturated with stories that are comparatively trivial.

Briefing documents were provided to reporters present. These books provided much of due diligence necessary for those reporters to explore the truth. However, neither Watergate-type coverage nor exposure of witness fraud has followed.

One of the witnesses reported how he became aware of 43 persons on the payrolls of major media organs while in fact working for the US government. Their job was to intercept ET-related stories and squelch, spin or ridicule. If we accept his testimony as factual, it provides a plausible explanation for the deafening silence following May 9th.

There is a bright spot in this situation. Some of the media did provide coverage, if only for a few days. This suggests that those who control media reporting do not have a monolithic power; they can be circumvented. The event did run on the internet and was seen by 250,000 viewers, despite “sophisticated electronic jamming” during the first hour (words attributed to the broadcast provider, not the Disclosure Project). Indeed, it continues to be fully documented at the Project’s web site.

Conclusions:

Since an expose of witness deceit or mass psychosis would itself have been a good, career-building story for some reporter, but no such story has appeared, I conclude that these witnesses are who they claim to be.

If these witnesses are who they claim to be, then they presented testimony they believe truthful. Yet no factual detail of any of that testimony has since been disputed in the media. Half a year is enough time to do the research. I believe the testimony is true as presented.

If the data is true as presented and the media are essentially ignoring what is indisputably the greatest story of our era, then the media are not performing the job they claim to do. Either they are being suppressed/censored, or they do not believe the public would find this subject interesting.

The tabloids continuously run stories on ET-related subjects, and polls show high public interest in the subject, so lack of interest value cannot be the explanation. I conclude that there is active suppression. This is corroborated by the witness claim of 43 intelligence operatives on major media payrolls.

Despite active suppression, enough coverage of the May 9th event happened in major publications and broadcast media to prove that the suppression can be thwarted. An event of significant enough impact and orchestration can break through the censorship. Millions of persons previously unaware of or dubious about ET-related technologies and their significance for ending our dependence on Arab oil have since become aware.

We live in a controlled society, one in which the control is secretive yet masquerades as openness. Yet, as proven May 9th, this control can be overcome by the concerted efforts of determined groups of persons. We must seek such opportunities again.

Jacob Haqq-Misra and Seth D. Baum (2009). The Sustainability Solution to the Fermi Paradox. Journal of the British Interplanetary Society 62: 47–51.

Background: The Fermi Paradox
According to a simple but powerful inference introduced by physicist Enrico Fermi in 1950, we should expect to observe numerous extraterrestrial civilizations throughout our galaxy. Given the old age of our galaxy, Fermi postulated that if the evolution of life and subsequent development of intelligence is common, then extraterrestrial intelligence (ETI) could have colonized the Milky Way several times over by now. Thus, the paradox is: if ETI should be so widespread, where are they? Many solutions have been proposed to account for our absence of ETI observation. Perhaps the occurrence of life or intelligence is rare in the galaxy. Perhaps ETI inevitably destroy themselves soon after developing advanced technology. Perhaps ETI are keeping Earth as a zoo!

The ‘Sustainability Solution’
The Haqq-Misra & Baum paper presents a definitive statement on a plausible but often overlooked solution to the Fermi paradox, which the authors name the “Sustainability Solution”. The Sustainability Solution states: the absence of ETI observation can be explained by the possibility that exponential or other faster-growth is not a sustainable development pattern for intelligent civilizations. Exponential growth is implicit in Fermi’s claim that ETI could quickly expand through the galaxy, an assumption based on observations of human expansion on Earth. However, as we are now learning all too well, our exponential expansion frequently proves unsustainable as we reach the limits of available resources. Likewise, because all civilizations throughout the universe may have limited resources, it is possible that all civilizations face similar issues of sustainability. In other words, unsustainably growing civilizations may inevitably collapse. This possibility is the essence of the Sustainability Solution.

Implications for the Search for Extraterrestrial Intelligence (SETI)
If the Sustainability Solution is true, then we may never observe a galactic-scale ETI civilization, for such an empire would have grown and collapsed too quickly for us to notice. SETI efforts should therefore focus on ETI that grow within the limits of their carrying capacity and thereby avoid collapse. These slower-growth ETI may possess the technological capacity for both radio broadcasts and remote interstellar exploration. Thus, SETI may be more successful if it is expanded to include a search of our Solar System for small, unmanned ETI satellites.

Implications for Human Civilization Management
Does the Sustainability Solution mean that humanity must live sustainably in order to avoid collapse? Not necessarily. Humanity could collapse even if it lives sustainably—for example, if it collides with a large asteroid. Alternatively, humanity may be able to grow rapidly for much longer—for example, until we have colonized the entire Solar System. Finally, the Sustainability Solution is only one of several possible solutions to the Fermi paradox, so it is not necessarily the case that all civilizations must grow sustainably or else face collapse. However, the possibility of the Sustainability Solution makes it more likely that humanity must live more sustainably if it is to avoid collapse.