 
#

# Articles From the Orbital Frontier

### by

### Mike Combs

######  mikecombs@aol.com

###### Copyright © Mike Combs

#

# Index

The Advantages of Space Living Over Planetary Living

Anatomy of a Claimant

Crossroads

I Have Seen the Enemy...

Are We Alone In the Galaxy? The View from the High Frontier

The Tragic Tale of the Mayi-Mayi

Been There, but Have We Really Done That?

The Case for Space

Building Dreams from Moondust

Somewhere Else Entirely

Averting Armageddon, with ROI
I used to write for the Fanzine of a Star Trek club, and sometimes used this forum for the discussion of High Frontier-type concepts. The following article began as a paper written for a college seminar hosted by Gerard O'Neill in 1981 at Oklahoma University, and was later modified for a Star Trek audience and published in one of the club newsletters.

#

# The Advantages of Space Living Over Planetary Living

### by

### Mike Combs

######  mikecombs@aol.com

###### Copyright © 1994

Much of Star Trek deals with colonies on Earthtype planets in other solar systems. But do we have any assurances that Earth-like worlds are as common in the Milky Way galaxy as they are in Hollywood, California? The future scenario that Gene Roddenberry presented seems clear enough. We would build cities on the moon, colonies on Mars, habitations wherever there was solid ground underfoot and gravity to keep you from drifting away. We occasionally see orbiting star bases, sure, but these are only way stations, refueling depots, laboratories. The crew can look forward to going home on completion of their tour of duty. Even if "home" is not Earth, then it is surely a planet, or at least a moon. These lines of thought are no different from what serious futurologists predicted and went completely unchallenged until the work of Professor Gerard K. O'Neill.

In 1969 O'Neill asked some of Princeton University's finest science and engineering students the following question: Is the surface of the Earth really the best place for an expanding industrial society? After some initial research was done, it seemed that the best place for our technological civilization is not on Earth or even on a planetary surface. A space habitat, orbiting in free space, would seem to have many advantages over any planetary home.

A space habitat will most likely be in the form of a sphere pressurized with air and spinning to simulate gravity. Sunlight is brought in with mirrors and windows. The interior can be landscaped to look very much like Earth. Hauling up the materials to construct this miniworld from Earth's deep "gravity well" would make the project too expensive to even consider, so we will use lunar materials that will require only one twentieth of the energy for their retrieval. The moon will provide oxygen, silicon, aluminum, and titanium. The asteroids can supply carbon, hydrogen, and nitrogen.

When the calculations were finished, it seemed evident that planets actually represent the hard way to go about doing things. A planet uses a tremendous amount of mass to create a gravity field and hold down an atmosphere, while a simple rotating, pressurized structure can achieve much the same effect. A good illustration of this principle is the fact that the asteroid belt alone contains sufficient resources to create, in the form of space habitats, three thousand times the land area of the Earth. However, if all of the asteroids were lumped together into a planet, that planet would be tinier than our moon. Besides this incredible economy of mass, are there other advantages of space living over planet living?

There has been much talk about becoming a solar society, but thus far it has been "talk" only. There is a good reason why we cannot shift over to a full scale solar economy and it is because solar energy is inconstant here on the surface of the Earth. Solar power is blocked by the shadow of the Earth at night, is interrupted by cloudy weather, and even on a "clear" day is filtered by miles of atmosphere. Consequently, we have obtained energy by constant, although indirect, means (I.E., fossil fuels).

In space, outside the shadow of the Earth, solar energy is constant and reliable. The builders of an aluminum smelting plant in space can confidently count on using solar energy to power their facilities without worrying about energy shortages, the rising cost of fuel, or environmental impact. Any time we go down to a planet, we will be faced with limitations on the amount of solar energy that we can use. Planets with atmospheres, in particular, not only further limit the use of solar power, but also have weather that must be given consideration when building large structures.

Although Star Trek's artificial gravity remains a fiction, a space inhabitant need not do without gravity as long as a habitat can be rotated. In space, one can have gravitational freedom. Any G force, from zero, to a fraction, to full, to in excess of a G can be produced by the appropriate rotational speed or lack thereof. Planets, on the other hand, have gravities that can't simply be turned off. Gravity places limits on the efficiencies obtainable for transportation. There is reason to believe that certain materials can be made in zero G that either cannot be made, or can be made only in small amounts, in a gravity field. Gravity also limits the size of structures that we can build on a planet. In space there is no reason why artifacts many cubic kilometers in volume cannot be built.

When we talk about a planet we are talking about a large but nonetheless finite environment. When we talk instead about living in space we have moved into the realm of the infinite. The resources of the Solar system are beyond human comprehension and the resources of the universe are as close to infinite as we need concern ourselves with. Using these materials to construct space colonies, we can provide all of the land area that any foreseeable population growth could require. With industry moved into space, our civilization could evolve toward what we see in Star Trek: a society enjoying all of the benefits of high-tech living without the disadvantages of pollution and destruction of the natural environment.

When we speak of bringing in extraterrestrial materials or energies we are discussing the creation of new wealth, not merely the redistribution of wealth already here. Isaac Asimov, the famed science writer, has observed that energy derived from space would not be geography bound. There would no longer be energy rich or energy poor areas. The same can be said of space resources. A shipment of asteroidal steel can be sent to one part of the planet as easily as another.

If these ideas are correct, then by the 23rd century there could conceivably be more people living in space than on Earth. The surface of our world, free of the major, voracious, polluting industries could be restored to a more natural, park-like form. Earth's main industry would then be tourism. The "Star Trek scenario" of searching through innumerable solar systems for a place to live where you don't have to carry your air in a bottle may become unnecessary in a universe where you can manufacture your own miniworld to your own specifications.

One of the most profound points of the space colonization concept is that now any star system can be inhabited. Nothing would delight a space colonist more than, upon arriving at another solar system, discovering rings of asteroids but no planets. What use would he/she have for steep gravity wells? The assumption that other intelligences in the universe might use similar techniques to colonize space vastly increases the odds that we will find them. On the more practical side, man's options are also vastly increased. If we use the technology that we have wisely, we can utilize all of the energy and natural resources that we and our children could ever need. Once man is out into space there will be no more limits to growth. With the seed of man spread throughout the galaxy the human species would, in effect, become immortal.

And if we ever did encounter an Earthtype planet in our journeys it would indeed be an interesting place to study. Or perhaps to set up a tourist stop.
"The Amazing Randi" is a magician who got upset seeing people promoting themselves as "psychics" using conjuring tricks which he recognized from his own profession. Though now retired, he has long been a leading figure in the skeptic community. In addition to founding The James Randi Educational Foundation (JREF), he has a standing offer of over one million dollars for any paranormal demonstration meeting mutually-agreed-to standards for success. For some reason, most psychics seem to have an excuse not to be tested.

When the 1 Million Dollar Prize offer first went up, Randi was willing to test anyone who could follow the application process. But no matter how different the claims may be of those who say they want to be tested by Randi, it seems they all use the same rhetoric, objections, and dodges. If you've seen one claimant, you've pretty much seen them all. Here's my summary of one particular case I happened to witness.

This article also appeared in the February 2000 issue of **The North Texas Skeptic**.

#

# Anatomy of a Claimant

### by Mike Combs

###### mikecombs@aol.com

I recently found myself on a maillist regarding a potential claimant for the James Randi prize (a homeopath this time). As I observed the complex verbal sparring of the would-be claimant, and witnessed his non-stop piling on of issues, concerns, and conditions, it occurred to me that I'd seen this performance before.

There seem to be two kinds of claimants. One is the self-deluded type who honestly believes they have the powers they claim. These can generally be successfully negotiated with to an actual testing of their abilities. They're genuinely baffled when they fail (although surprisingly their belief system usually survives the experience intact). But the other kind secretly knows they can never win Randi's money, and they all seem to use the exact same techniques and methods.

While thinking of the latter, I sent the following article in to the maillist:

### * * *

Here's an unsolicited point of view from an uninvolved amateur:

I've been mulling over two different scenarios, and how I would respond in each case.

First, let's say that I was the promoter of a fantastic claim, and I not only believed in this claim very strongly, but had verified that the claim was true. As a scientist, my tool for this would have been the double-blind trial: the only surefire way to eliminate the possibility that I was just kidding myself. How would I react to the Randi Challenge?

First, I would certainly take it. I would follow the letter of the Challenge, and do everything required of me by Randi, because I would want to bend over backwards to avoid any perception that I was trying to be in any way difficult. I would agree to most any condition Randi insisted on, as the truthfulness of my claims would give me such an overwhelming advantage that I could afford to be generous. In return, my list of conditions would be short or nonexistent. After all, it's Randi's Challenge, and Randi's money, not mine. If I'm right and know it, I require nothing but a fair chance to prove my claim. No matter how high my self-confidence, I would keep my comments relatively modest, like "We think we stand a good chance of winning your Challenge". Because who likes a braggart? If Randi happens to respond with rudeness or belittlement, I would take great pains to avoid responding in kind. Because everybody loves a gentleman, and is inclined to think he has something on the ball.

Now let's say that I was the promoter of a fantastic claim, but down in the deepest parts of my psyche (the part that I try to avoid looking at as much as possible), there was at least a strong suspicion that it was all total nonsense. But maybe I've become so emotionally invested in the subject that I can't back out now. Maybe there's money involved. But bottom-line, it's in my best interests for the nonsense to continue. How then do I react to the Randi Challenge?

It would be preferable to ignore it, but to my great annoyance, people keep throwing it in my face when I'm promoting my fantastic claims. In my heart of hearts, I know that I'll never win the Challenge. How do I resolve this frustrating dilemma?

I would have to engineer a situation where I could later make the claim that I applied for the Randi Challenge, but was "turned down". I have to invent an image of Randi "running scared" from the sacred truth I was promoting.

So I would send an e-mail to Randi, and refer to that as my acceptance of the Challenge, pretending not to know that the terms of the Challenge involve sending in a signed, notarized form. I would insist upon condition upon condition, all designed to give the appearance to an observer that Randi could not be trusted with someone's lunch money, much less to administer the tests fairly. At the same time, I would make remarks such that the money was practically mine already, and pretend to a concern about collection.

I would work diligently on affecting an air of exuded confidence. But still, I would discuss lawyers, as though my winning the Challenge and Randi refusing to hand me my money were something which had already occurred, and not just a personal fantasy.

I would invoke some scientific-sounding principle in support of my claim. It would be best to pull from some scientific oddity sufficiently well-known among laymen to be a subject of cocktail party conversations and sf TV shows, but of course I would put my own spin on it, or maybe turn it on its head. **1/** Whether it had any conceivable connection with my claim is, of course, irrelevant. After all, the goal is merely to make my promotions sound vaguely scientific to anyone largely unacquainted with real science (which is to say, the vast majority of people).

If Randi tosses an insult my way, I'll respond with one well below the belt. If my enemy's not going to be a gentleman, why should I be? I would prefer that Randi come to hate me to the extent that he would view any further dealings with me with extreme distaste.

As my spurious claim on the Challenge progressed, I would need to continue to pile condition upon condition to the Challenge, rewriting it as though it were my own Challenge and my own money, until any potential agreement finally collapses under the ponderous weight of it all. The goal is to provoke Randi until he throws his hands up in the air in disgust and frustration, and walks away.

At last we have achieved what we sought from the outset. From now on, we can regale potential customers or converts with the story of how Randi "refused to allow us to take the Challenge".

Now I ask anyone capable of looking at this objectively: Who is following which scenario?

Regards,  
Mike Combs

### * * *

The homeopath promptly E-mailed me to charge that my essay was primarily directed toward him. Whether he saw himself in the first claimant described, or the second, he did not indicate. I was chided for spending my time making up a scenario about him when instead I could have been inquiring about the new discovery which he was sharing with me. He invoked Galileo (as cranks unvaryingly do), and told me to keep writing my scenarios.

He correctly pointed out that he did indeed send in a signed, notarized application. So I suppose we should call the subject of this article a "composite claimant".

James Randi presented me with yet a third scenario: that it was possible for a potential claimant to truly believe their claim because they don't understand science (while still having a working knowledge of the terminology), and that they might simply want to rant and rave from pure orneriness.

Postscript:

In the weeks and months to follow, the homeopath did indeed continue to push Randi's buttons (chiefly by spamming Randi's E-mail account) until negotiations were ultimately terminated.

Randi had been negotiating via two intermediaries who, while believers in homeopathy, were capable of being reasonable. It got down to an agreement on the test method, and an inquiry from Randi if the month of November was suitable. At that point, the homeopath launched into an "investigation" of Goldman, Sachs & Co., the accounting firm with which the prize money lies. When they were not as responsive to his inquiries as he thought this weighty matter deserved, he declared them in on it with Randi to deny him his money.

By this point, earning the prize had somehow gone from passing a test to merely providing Randi with the test method. The homeopath's former allies have given up on the negotiations, and at this point no onlooker holds out any hope that any kind of test will ever be performed. The homeopath continues to post to newsgroups on the subject of Randi's refusal to hand over the million.

**1/** In this instance, the claim on the Randi Prize concerned homeopathy, which is the belief that medical benefits can be had from solutions which are so diluted that none of the original molecules remain. This effect is attributed to some type of memory which water molecules are said to possess. The operative force of "water memory" offered in this particular case: the white hole, which as we all know is the exact opposite of the black hole, with matter and energy pouring out rather than in.

That follows... doesn't it?
I used to write for the Fanzine of a Star Trek club, and sometimes used this forum for the discussion of High Frontier-type concepts. The following article was written for a Star Trek audience and was published in one of the club newsletters. It compares two different futures: One with space travel, and one without.

In the years since this article was written, we've seen absolutely none of the dire predictions of the "Limits to Growth" crowd come to pass. These days, I worry less about resource depletion or overcrowding and more about increasing stultification and regimentation of human society. Still, I think space equally provides a solution to those slightly-less-dire problems.

#

# Crossroads

### by Mike Combs

###### mikecombs@aol.com

###### Copyright © 1994

Imagine two different scenarios, if you will:

Scenario one: Someone stands up and says, "We shouldn't be spending so much money on sending people into space when we could instead be spending it to solve all of our problems right here on Earth". Everyone else says, "Sit down and shut up. Let's all go into space. It'll be fun!"

The international space station Alpha is built. Research conducted in the zero gravity environment results in the creation of new metal alloys and pharmaceutical vaccines that cannot be made in a gravity environment. The demand for more space stations becomes so great that the space shuttle begins to bring its enormous external fuel tank into space so that they can be re-outfitted for additional stations. Some stations are designed in a baton shape, and rotate for artificial gravity so the crews can begin staying up for duty shifts longer than a couple of months.

The X-33 spaceplane program comes to fruition, resulting in a space transportation system far cheaper and more reliable than the old space shuttle. This, combined with the increasing number of stations makes possible a new multi-billion dollar space enterprise: orbital tourism.

Space station Alpha is expanded to serve as a staging post for the next step: a return to the moon. This time we go not to plant flags, but to gather resources. A small mining camp is set up. Lunar soil is scooped up, sintered in a solar furnace into spheres about the size of a base ball, and launched into space. Since the moon has no atmosphere, and since its gravity is only a fraction of the Earth's, there is no reason why rockets would have to be used to launch the ore into space. A device called a mass-driver is built on the lunar surface. Essentially a kilometer-long solar powered electromagnetic accelerator, the mass driver launches the ore up to an ore catcher in space behind the moon. When a good-sized load is accumulated, an ore carrier transports it to a manufacturing facility in a high Earth orbit.

The manufacturing facility uses the constant solar energy available in space to smelt the ore into silicon, aluminum, titanium, nickel, iron and other pure elements. A surprising by-product of this ore refining operation is tons of oxygen. Obviously useful for breathing, it's also the heaviest part of both water and rocket fuel. Space operations become increasingly independent of Earth.

The presence of manufacturing capability and large amounts of resources already in a high orbit make possible the construction of vast engineering projects in space that would be impractical to support from the surface of the Earth. The space manufacturing facility begins using the silicon and metals to form the components of the first Solar Power Satellite (SPS). It's a gigantic array of solar cells in a geosynchronous orbit around the Earth where the constant, 24 hour a day sunlight at this altitude can generate electricity non-stop. The energy is beamed down to a receiving antenna on the surface via a microwave beam where it is converted back into electricity. This microwave beam had been studied thoroughly, and no harmful environmental effects were found. The energy is cheap, clean and plentiful.

The market for new sources of energy grows as the poorer nations of the Earth struggle to raise their standard of living to that enjoyed by the industrialized nations. As they do so, they become less interested in radical politics and regional disputes and more interested in pursuing the good life. The construction of new power satellites accelerates to meet the increased energy demand. More energy is being used, but since most of the waste heat is in space, global warming actually goes down.

As the SPS program expands, at first thousands, then tens of thousands of people associated with SPS construction begin to live for longer and longer periods in space. However, the workers soon become dissatisfied with their accommodations. Gradually, a part of the output of the manufacturing facilities is diverted to the construction of a large space habitat which creates an Earth-like environment for its inhabitants.

The space habitat is a sphere or cylinder rotating to provide simulated gravity equal to Earth's. Sunlight is brought into the interior with mirrors. Lunar soil is landscaped and planted to produce a very natural appearance. Later, much larger habitats are built big enough to have a blue sky with cloud formations and natural weather.

As we go farther afield for space resources, the asteroid belt is opened up. The asteroids provide elements the moon lacks like hydrogen, carbon and nitrogen. All dependence on Earth for supply is finally severed. With large human populations now scattered throughout the solar system, no single global catastrophe can wipe out our species.

While SPS construction continues to expand, habitat construction becomes a bigger and bigger part of the enterprise. In addition to providing housing for SPS and other space-related workers, markets begin to open up for all kinds of emigrants from Earth. Many want to live in space due to the superior living conditions afforded by the space habitats. Others feel the pull of a new frontier.

The improvement of economic conditions in the developing nations seems to also be accompanied by a trend towards lower birthrates. Still, the population of the Earth does continue to grow. More and more stringent (and unpopular) population control laws are instituted. Although no space transportation system can keep up with the number of children being born, at least space provides an option. One can either stay on Earth and live with the population control laws, or immigrate into space so that one can have their Walton clan. "Don't worry about living space," they'll say, "we'll make more". Now when you ask someone at a cocktail party what they do and they say they're into real estate, they may not mean sales. They might mean manufacture.

In time, there are two civilizations: Earth and Space, with the population of the latter eventually exceeding the former. The asteroid belt alone would provide the resources to build sufficient habitats to equal 3,000 times the livable surface area of the Earth. Space habitats make the entire solar system a home for humanity. With most industrial manufacturing activity taking place in space, the Earth's primary industry now becomes tourism. Interest then rises in restoring the natural environment to what it was before the industrial revolution.

Eventually some habitats begin to drift away from our star to take up residence around other favorable stars. Now not even a super-nova could kill off the human race. Then an Alpha Centarian named Zephram Cochrane invents something called a warp coil and... oh well, you know the story from this point.

Scenario two: Someone stands up and says, "We shouldn't be spending so much money on sending people into space when we could instead be spending it to solve all of our problems right here on Earth". Everyone else says, "Yeah, that sounds right. Let's do it."

All national space programs are disbanded. The money is put into social programs which expand their budgets by less than two percent. The spending is about as successful as all past social spending. None of it reduces prejudice, makes dishonest people honest nor selfish people generous.

Each year that passes by sees more and more people pursuing less and less natural and energy resources. Greater populations squeeze into the same living space resulting in increasing social tensions. Famines begin to spread.

The burning of the remaining quantities of fossil fuels creates a shortage of plastics, fertilizers and other petroleum-derived substances. Eventually, the resulting global warming raises ocean levels, inundating all coastal cities. Concern for the environment vanishes as everyone does whatever it takes to maintain their accustomed lifestyle.

The poor nations become poorer. The rich nations jealously guard their rapidly dwindling wealth. International tensions rise. Disputes intensify. Some nations, frustrated with the inequities and convinced that they have nothing left to lose, try to use nuclear blackmail to get their way. There are so many nuclear devices left over from the excesses of the Cold War that it is not difficult for anyone to get their hands on them. Some are home-made from the tons of fissionable material which resulted from the expansion of the nuclear industry when fossil fuels ran out. Entire capitals vanish instantly in blazes of atomic fire.

Some scientific experts point to the moon and the asteroids as possible sources of the materials now so desperately needed on Earth, and wonder about harnessing the sun's energy in space, but to no avail. Even the wealthiest nations can no longer afford space travel.

Social structure breaks down and resource depletion intensifies. Our technological level regresses to that prior to the industrial revolution; only we are in much worse shape for advancing than we were back then. All of the easily-retrieved resources of coal, oil, metals and timber are gone.

As starvation closes in, some folks invent little food wafers called Soylent Green. "We'll tell people that it's made out of plankton from the oceans," they say, "although really....", well, you know _this_ story from this point too.

One of the wonderful things about science fiction is that it shows us possible futures. Some look like nice places to live. Some we should desperately try to avoid. It may be a slight exaggeration to say that the difference between a world with space travel and a world without is the difference between Star Trek and Soylent Green. However, I'm convinced that there is at least a germ of truth in this assertion.

Perhaps I'm preaching to the choir here. One presumes that anyone who is a fan of Star Trek is favorably disposed towards space travel. But maybe you could keep this article handy and pull it out the next time a friend advocates "solving all of our problems here on Earth first".
Here's an article I wrote which touches on extraterrestrial conspiracies, The X-Files, Star Trek, and the intellectual decline of popular culture. It deceptively starts out like a review of the movie "The Arrival". But like the aliens of that movie, I have a hidden agenda.

This article also appeared in the February 1997 issue of **The North Texas Skeptic**.

#

# I Have Seen the Enemy...

### by Mike Combs

######  mikecombs@aol.com

###### Copyright © 1996

Rented "The Arrival" last night. Pretty slick flick. Charlie Sheen was occasionally annoying when his husky whispers dipped down below the range of audibility, but his character was respectable, maybe even likable, and certainly worth rooting for. The suspense works, the science was plausible, and the movie has way-cool computer-generated aliens.

For those who haven't seen it yet, the plot is this: The aliens were among us in human form, and (as is always the case in such situations) were covertly trying to take us over. Specifically, they were dumping tons of CO2 into the atmosphere to speed up the Greenhouse Effect. It was their version of terraforming; an attempt to make the Earth less suitable for _us_ and more to _their_ liking.

"We're not doing anything to you that you're not already doing to yourselves," one of the human-guised aliens sneeringly tells the hero. "All we're doing is accelerating the process. What it will take you a hundred years to do, we will do in ten."

This got me started thinking. Suppose I were a nasty alien from a technologically superior race, and was looking with alarm at this planet populated with homosap's who are breeding like mad, and growing more technologically powerful each day. If I had the ability to infiltrate their society and covertly mess with their culture, what would I do to try and keep them in their place (and out of my neighborhood)?

Encouraging the widespread acceptance of addictive drugs would be a good start. Numb those disturbingly-well-developed brains with chemicals. A clever strategy would be to redefine their language such that one of their most-widespread drugs was not even referred to as a drug, but by another word. This despite the fact it annihilates brain cells, lowers sensible inhibitions, destroys internal organs, kills millions on the highways, and wrecks families and careers.

Hey, we're off to a great start. Now we do everything we can to encourage paranoia. If we can get these carbon-based units to believe everything's controlled by a shadowy group, then they can take comfort that whenever they fail, it's not _their_ fault. They can't get ahead because of The Conspiracy. This will be particularly effective with races which have been treated badly by others in the past, and will interfere with their struggle for equality.

Breaking the Earther's will is all well and good, but specifically I want them to stay out of space. I would obscure the immediate social and economic benefits of space travel, and suppress all knowledge of potential future benefits. The last thing I want is those big-ugly-bags-of-mostly-water tapping into the energy and resources of space, or proliferating in space habitats. I'd start a campaign which asks the question "Which are we going to spend our money on, space, or helping humanity?" as if the two issues weren't intimately-connected. I want to keep the Earth-Worms planet-bound; forever, if possible.

But I don't just want them to give up on space. I want them to discard science and technology altogether. Knowledge is power, and I don't want them to have any. I would instill in their youth a contempt for science, such that they so torment those who choose a scientific education that few are willing to go that route. The fewer scientists those grubby hairless apes turn out, the better.

I would encourage religious groups to go into the science classroom, and give battle over the teaching of basic scientific facts.

This is starting to work, but we're just not getting the message out effectively enough to suit me. I would look at a planet bathed in innumerable TV transmissions, and know exactly where my forces needed to come into play. Hollywood, here I come.

I would try to ensure that the entire population watches television, instead of reading books. Books can put profound ideas into their misshapen heads, television can only titillate. I would ramp-down their attention spans, until it was insufficient to let them learn anything of worth.

Manipulation of television could further our earlier plan for making science nerdy. Portray scientists as laughable, abnormal social misfits who can certainly cause lots of trouble, but can never participate in the solution. If anything, make them an impediment to saving humanity. This will have the pleasing effect of reducing the risk of real scientists going off and saving humanity. It would be most convenient if the human race would destroy itself and save us the bother, and scientific knowledge is the biggest threat to this scenario.

But it's that rapidly-advancing technology which might lead the-bipeds-with-the-big-heads to build starships. Portray technology as the cause of the problem, but never the fix. Since in all likelihood it's their large multinational corporations which would develop the technology to build those accursed starships, use television to promote the belief that corporations are the root-cause of all evil in their world instead of political avarice, religious and racial intolerance, and mental illness. As long as the dramas are more entertaining than their evening news, maybe the huemons will never learn any better.

My ideal, perfect TV program should really push that "hidden conspiracy" thing. It would have two investigative characters: One who gravitates to the most outlandish, paranormal explanation, and is almost invariably right; and one who prefers the most rational, scientific explanation, who is almost invariably wrong. Make the latter a poor advocate of the rationalist point of view. I would make the show so slickly-produced, and so genuinely entertaining, that even those opposed to the philosophy being advocated still feel impelled to watch. Maybe we'll get some converts.

This show would go a long way towards encouraging a belief in magic amongst these savages, which certainly works to my advantage. After all, when you enter into the midst of a primitive tribe, you only have to worry about the tribesmen armed with spears. The ones armed with voodoo are at the bottom of your list of worries.

But there would be one show I would _hate_ above all others, and would utterly destroy if allowed to.

Star Trek.

Star Trek portrays a positive future in which their disgusting race has quit squabbling amongst themselves, and worked together to solve their global problems. Although its science bears little resemblance to reality, and it frequently descends into meaningless techno-babble, Star Trek is still dangerous because the characters' scientific knowledge is viewed as an asset, not a liability.

On my ideal, perfect show, I'm able to weekly reinforce the idea that there's no use in investigating the universe. Try as you might, you can never solve the mystery because The Conspiracy won't let you. Each episode ends with the protagonists no closer to the truth than they ever were, only with more befuddling mysteries before them. I'm hoping that with enough seasons of this, Earthlings will eventually decide examining the universe is not even worth bothering. But then here's Roddenberry's evil spawn contradicting my message. Each episode ends with questions answered. Every week, mysteries yield to scientific investigations. The universe is ultimately a knowable place. I don't want the Terran Pigs to find out about _that_!

Worse, the characters in Star Trek frequently use technology to solve problems and to help people. This is all in direct opposition to the message I'm getting out in every other show on the air. We can't stand for this.

Worst of all, the show provides a concrete vision of a tomorrow where humanity is cruising about the galaxy in starships. That's the absolute _last_ thing we want. Whatever the Earth Scum can visualize, they can eventually create, if they want it badly enough.

But wait; maybe we could infiltrate Star Trek. Maybe we could arrange for an episode on Next Generation where it's revealed that Warp Drive damages space. This would bring the show more into alignment with the theme of my other shows: Technology can only hurt the natural world. Best to suppress it whenever possible.

I could arrange an episode of Voyager where a scientist has to surrender her rational view, and embrace a backward planet's mysticism in order to save the life of a dear friend. Maybe I can get one of the actors to direct that one; the fans love that.

The best move would be to invent a villainous race of grotesque half-men/half-machines. The message would be clear: Keep technology at arm's length, lest it transform you into a pasty zombie. The last thing I need is for these mildly-intelligent monkeys to hit on the idea of putting chips into their brains. The result might be a new, advanced form of intelligence capable of doing things neither man nor machine could accomplish alone. After all, such an intelligence could compete with _my_ form of intelligence.

_Hey_ , "The Arrival" is right after all. Evil aliens wouldn't do anything to us that we aren't already doing to ourselves. This is news that should cause us great cheer.

"Are you crazy?" you ask. "Isn't this all terrible?"

Not really.

If there really _was_ a more-advanced race of hateful aliens in our midst who wanted us out of the way, we would be screwed. Screwed the same way as the American Indians when Columbus and crew showed up. Screwed the same way as the Aztecs when Cortez and company arrived.

But if we are, after all, only doing it to ourselves, then at least we have a choice.
What, if anything, might the orbital space habitat proposal have to do with _extraterrestrials_? This paper is an attempt to use the "High Frontier" perspective to investigate the mystery of whether or not there are other technological races in our galaxy.

#

# Are We Alone In the Galaxy?  
The View from the High Frontier

### by Mike Combs

######  mikecombs@aol.com

One of the most challenging mysteries facing mankind is this: Are we alone in this vast galaxy in which we find ourselves, or are there other technological civilizations in other star systems? We concern ourselves with technologically-advanced civilizations; for these are the ones which we could conceivably make contact with, either by radio or starship. Is there anyone else with whom we share the tool-using experience, or is our situation unique?

The study which is called SETI (Search for Extraterrestrial Intelligence) is plagued by two disturbing puzzles. One is this: If the galaxy is an inhabited place, then why have increasingly-sophisticated attempts to discover the radio transmissions of other races been, thus far, unsuccessful? Why the Great Silence? The other has been called the Fermi Paradox (most simply, "Why aren't they here?").

It is often helpful to look for different perspectives when trying to figure out a mystery. This paper is an attempt to approach this riddle from a seldom-used perspective.

In 1969, physicist Gerard K. O'Neill at Princeton University's Institute for Advanced Study began to work out a scenario for the future expansion of the human race into space. He devised what has come to be known as the Space Settlement proposal, which is the idea that the best way for humanity to establish colonies off the Earth may be to use space resources to build enormous, artificial habitats in orbit. It turned out that such habitats could be designed from the beginning to be surprisingly Earth-like.

Up until then, most thinking had centered on the idea of colonizing the surfaces of other planets, sometimes after modifying their environments to make them more Earth-like (called terraforming). But orbital settlements seemed to offer many advantages over any planetary home:

  * 24-hour-a-day access to sunlight, both for life-support and industrial use

  * Location at the top, rather than the bottom, of a gravity well

  * Convenient access to zero gravity

  * Complete control over the gravity (via rotation), the weather, and other aspects of the environment

  * Limitless potential for expansion

Gerard O'Neill championed this idea in several scientific papers, starting with one in **Physics Today**  , and wrote a book for the general public entitled **The High Frontier**.  Although his concepts were somewhat influential on space-related thinking, it can be argued that they are not yet as influential as the planetary paradigm. Interest in the goal of terraforming Mars, for example, remains high. What does this less-widely-appreciated perspective offer us when considering the question of our uniqueness in the galaxy?

Here, I think, is where the divergence of opinion begins. I have noted that those who tend to believe in a planetary future for humanity also tend to hold out the hope for advanced civilizations somewhere nearby. Those who foresee a space-dwelling future for the human race tend to suspect that we are alone in this galaxy. The reason being that space-dwelling civilizations can be expected to so change the physical characteristics of the galaxy that the signs of their existence would be both obvious and unmistakable.

In 1959, Freeman Dyson (also with the Institute of Advanced Study) wrote a paper  on a concept that has since come to be known as the Dyson Sphere. His argument was that an advanced extraterrestrial civilization, regardless of the nature of its technology, is going to experience a constant increase in the amount of energy needed by that civilization. In time, the energy requirements would exceed the amount of energy conceivably available on the civilization's planet. At that point, there would be no recourse but to begin tapping the solar energy available in space. Dyson saw this process continuing until the home-star of the civilization was so completely surrounded by solar energy collectors and habitats that, from outside the system, the solar output would be severely dimmed, or perhaps totally obliterated.

It should be noted at this point that Dyson never proposed what the science-fiction writer has come to call a Dyson Sphere: a solid, continuous, hollow sphere. Such a structure would collapse under the gravitational pull of the sun at its center. A sphere could be spun to support the "equator", but there would be nothing to prevent the collapse of the "poles". Dyson instead hypothesized innumerable individual solar collectors, each in its own independent orbit. The term "Dyson Swarm" might be more accurate.

Dyson suggested that rather than searching for indicators of extraterrestrial civilizations in the radio spectrum, perhaps we should instead be looking in the infrared. A point source of energy equivalent in wattage to the output of a main-sequence sun, but entirely in the infrared spectrum, is precisely what we should expect a solar system to look like, provided that some industrial civilization was making 100% use of the star's solar output.

We have thus far found no such indicators. The coolest infrared sources located to date are consistent with dim, red dwarf stars; cool for a sun, but far too hot for a Dyson Swarm.

So we are left with the conclusion that whatever else may be out there in the galaxy, there are no nearby civilizations which harness most or all of the output of their local sun. But is it an inevitability that all technological civilizations _must_ ascend to Dyson Swarm status?

Another type of extraterrestrial construct visible from cosmic distances can be found in Carl Sagan's science fiction novel **Contact**.  In it, a radio astronomer is informed that some of the extremely energetic phenomena we have detected, like Cygnus A, are the "galactic urban-renewal programs" of astonishingly-advanced civilizations. But this should probably be taken as an ingenious and provocative idea for a science fiction story, rather than as a serious proposal. Certainly any universe in which black holes exist can have extremely energetic phenomena. Occam's razor (also mentioned in the book) suggests that any phenomenon which is explainable in terms of natural cosmic processes cannot be used as evidence for extraterrestrials.

So radio astronomers continue to scan the radio spectrum, looking for signals which are indisputably artificial. Gerard O'Neill was at least open to the idea that other technological cultures may exist in this galaxy. But one gets the impression he was never confident that a radio search for extraterrestrial intelligence would ever yield positive results. In **The High Frontier** he confessed (somewhat reluctantly) that one product his high-orbital manufacturing facilities would be excellent for would be the construction of an orbital version of Cyclops  , the SETI proposal for a vast array of intelligence-seeking radio telescopes.

Again, this was the High Frontier perspective in action. The "planetary mind-set" was that even if you wanted to build Cyclops off the Earth, the best location would be a crater on the far side of the moon, where the mass of the moon itself would shield the array from the radio noise of Earth. But O'Neill's proposal was a single radio dish in High Earth Orbit, five kilometers across, with a simple, disk-shaped aluminum baffle for a noise shield. Using thousands of miles of lunar rock for shielding was a bit of overkill; a millimeter of aluminum could do the job just as well.

Assuming both arrays were built from lunar resources, the only remaining issue was would the cost of lifting those resources from the moon plus the cost of the disk-shaped baffle be greater than the additional cost of building the array in a gravity environment where there was only access to solar energy half the time. Given the application of mass-driver technology to lunar ore-launching, the advantages of zero-G construction, and the simplicity of the shield, O'Neill felt the answer was no.

It is tempting to look at lunar craters and envision outfitting them as giant radio dishes, like the one in Arecibo, Puerto Rico. But craters are the wrong shape. They are hemispheres. Radio dishes require parabolic shapes. To make a parabolic dish in a lunar crater would require extensive excavation in the middle, or very high lifts toward the edges (probably both). It will never be as simple as laying aluminum grills all over the ground.

But the major disadvantage of the Lunar Cyclops system versus the orbital one would be its fixed, immobile state. It would only be able to look in the direction the moon was pointing it in. The orbital Cyclops could point in any direction desired. If it was in a sufficiently-high orbit, no part of the sky would be blocked to it. O'Neill painted a humorous scene of a scientist in the uncomfortable position of trying to explain these facts to the very congressman who had approved the billions of dollars for his Lunar Cyclops proposal. This after it was discovered that the Encyclopedia Galactica was being beamed our way, but we were getting less than half of it.

1981 saw the publication of **2081: A Hopeful View of the Human Future** , in which Gerard O'Neill went on to hypothesize replicators: machines which, given a supply of asteroidal ore and solar energy, can build a duplicate of themselves.  He then argues that any technological civilization in the galaxy can have easily placed a replicating space probe in orbit around every star of the Milky Way with only a modest investment; each probe reporting back to home base at the speed of light. The question then follows: If there is as many as one other civilization in the galaxy, where is the probe for our solar system? Either it is undetectable, or we are the first technological culture in the galaxy; the one which will eventually fill it with self-replicating space probes.

About ten years later, Marshall Savage wrote a book entitled **The Millennial Project, How to Colonize the Galaxy in Eight Easy Steps**.  His basic thesis was the following. Do you remember that "Genesis Effect" in Star Trek II: The Wrath of Kahn? That spherical shock wave which spread outward, and, everywhere it touched, converted dead, inanimate matter into living things and a clement environment? Well, if you want to know what the real Genesis Effect looks like, go find a mirror. _We_ are destined to expand outward from Earth in a spherical wave traveling at just under the speed of light, and in every sterile, lifeless place the wave touches, raw matter will be converted into lakes and flowers and children.

His orbital habitat designs are different from those of O'Neill's, chiefly because they asked different questions. O'Neill asked, "How Earth-like an environment can we create in space?" Savage asked, "How can we create a life-sustaining environment in space?" But one issue upon which they were both agreed was that space is where it's at. Although Savage spends some time discussing domed habitats on the Moon and Mars, his "Solaria" civilization  is indisputably over 99% orbital habitats. This is a simple consequence of the fact that such settlements can reproduce themselves endlessly. Planetary surfaces will always be limiting to growth.

Savage foresaw his orbital habitats eventually numbering in the trillions. Since their life-support system involved the growing of algae, he wondered if their massed numbers wouldn't filter the sunlight green.  And given that we are witnessing no such "greening of the galaxy"; he concludes that we do not share this galaxy with other advanced beings.

Even if extraterrestrials used a different type of life-support system, the argument remains the same. A star surrounded by trillions of artificial structures of any kind would show _some_ distinct change in its spectral signature, if only the infrared shift earlier hypothesized by Dyson.

According to Marshall Savage, our SETI astronomers are cupping a hand to their ear, struggling to catch a whisper, when what they are looking for, if it indeed exists, would be a deafening roar of radio noise.  Imagine ten trillion cell phones going off at once, and you begin to get the idea. The counter argument to this is that extraterrestrials might use some communications technology as yet beyond our ability to detect. Perhaps when we turn on the world's first tachyon receiver, it will hum with ten trillion conversations. But it seems odd that ET's would totally ignore the electromagnetic spectrum. Surely there are a few applications left around which radio is still good for.

So we have two different views of the future which lead to vastly different-looking universes. On the one hand, if we live in a reality where intelligent life is typically found on planetary surfaces, we might expect one inhabited planet in a few widely-scattered solar systems. Some systems might have two inhabited planets: the planet of origin plus another, nearby world which has been terraformed, and is marginally inhabitable. Probably no single planet could support a population much greater than around 10 billion individuals. So figure maybe 10 or 15 billion per solar system total. If only one out of a hundred systems have a planet which is either inhabitable or amenable to terraforming, then that is not very many beings out there. Perhaps we could look at the night sky, and be unable to distinguish such a universe from a cosmic wilderness.

But on the other hand, if we live in a Gerard O'Neill / Freeman Dyson / Marshall Savage-type universe, the picture is very different indeed. O'Neill calculated that the resources of the asteroid belt alone would be sufficient to build, in the form of orbital space settlements, more than three thousand times the habitable surface area of the Earth.  And the asteroid belt only represents the most convenient source of raw materials. We would still have Mercury, our Moon, and the moons of the outer planets for industrial feedstock. In a universe where technological cultures go the orbital habitat route, we can expect solar systems with perhaps hundreds of thousands of times the Earth's living space. Trillions of intelligent beings residing in hundreds of billions of space settlements. Moreover, we can expect _every_ solar system within reach of their starships to be so populated, not just the ones with certain planets with certain conditions orbiting certain-type suns. With orbital habitat technology in hand, even suns vastly different from our sun's spectral type can be colonized. All it takes is the proper color filtration.

If there is any truth to the Space Settlement concept, then we should expect a universe inhabited by intelligent beings to be lit up like a Christmas tree (at least where the infrared spectrum is concerned) with their cosmic-scale artifacts and construction projects. As Marshal Savage said, we could no more mistake that type of universe for a wilderness than we could confuse New York City with the Antarctic ice cap.

One objection raised against this logic is that perhaps ET's wouldn't concern themselves with such gross matters as reproducing themselves, or harnessing energy. Maybe they would devote themselves to some loftier goals of a spiritual (or at least invisible) nature. These assertions remain unconvincing. All of life, from slime molds to the reader, is driven by the same evolutionary mandate: proliferate and spread. It is difficult to imagine how life could develop in the first place other than via natural selection mechanisms. Although Extraterrestrials would doubtless move beyond Darwinian pressures when they entered their technological stage (as indeed we have begun to), by that point both their bodies and their minds would have already been shaped by their natural selection origins. The basic motivational imperatives would already be set, and couldn't be changed except by intentional self-reengineering.

But even this concept does not rescue the argument. If only one species out of a thousand retained its reproductive urges, that one race would be lords of the galaxy in only a few hundred thousand years, rapidly overwhelming the other, less fecund races. Perhaps many races might reengineer themselves to have no procreative desire. But the only explanation for either the Fermi Paradox or the Great Silence is that _all_ races _invariably_ do this _without exception_. Why this should be so is difficult to see.

Those with the traditional "conquer the planets" viewpoint believe in an inhabited galaxy because they can. Those who view the future from the "High Frontier" perspective tend to believe that we do not share the galaxy with other technological cultures, reasoning that the alternative is a galaxy which is so thoroughly-inhabited that the signs would be highly distinctive, and could not be overlooked.

Mike Combs  
February 1998

## Footnotes

1 O'Neill, G. K., "The Colonization of Space", Physics Today, Sept 1974. (Back)

2 The High Frontier by Gerard K. O'Neill, 1976, Bantam Books/SSI Press, ISBN: 0-9622379-0-6 (Back)

3 Dyson, F. J., "Search for Artificial Stellar Sources of Infrared Radiation", Science, vol. 131, pp. 1667-1668, 1959 (Back)

4 Contact by Carl Sagan, 1986, Pocket Books, ISBN:0-671-43422-5, pp. 363-365 (Back)

5 The High Frontier, pp. 188-196 (Back)

6 2081: A Hopeful View of the Human Future by Gerard K. O'Neill, 1981, Simon & Schuster, ISBN: 0-671-24257-1, pp. 258-264 (Back)

7 The Millennial Project by Marshall T. Savage, 1992, Little, Brown & Company, ISBN: 0-316-77163-1 & 0-316-77163-5 (Back)

8 Ibid. Chapter 6 (Back)

9 Ibid. pp. 313 (Back)

10 Ibid. pp. 347-349 (Back)

11 The High Frontier, pp. 8-9 and 246 (Back)

12 2081: A Hopeful View of the Human Future, pp. 259 (Back)
Based on a report by the Associated Press, this article details yet another cruel abuse of the human capacity for believing the fantastic. At the time, there was a war raging in the African nation of Zaire between government troops and rebels. Some of the rebels had induced young children to fight in their battles by claiming that they could provide them with a magic which would confer invulnerability.

#

# The Tragic Tale of the Mayi-Mayi

### Mike Combs

######  mikecombs@aol.com

###### Copyright © 1996

From the Associated Press comes a story detailing yet another cruel abuse of the human capacity for believing the fantastic. Elsewhere in this webpage I have commented that one of the problems with belief in the paranormal is that the unscrupulous use them to bilk the credulous, and that such beliefs can sometimes have deadly results. Here is a situation where the reprehensible use belief in magic to not only take advantage of the naive, but to sometimes send them to their deaths.

In the African nation of Zaire, there is a war raging between government troops and rebels. It is not the intent of this article to debate the justness of this war, or the correctness of either side. The only point I wish to make regards the warping of reality for political gain.

As has happened far too often in some wars, children have been enlisted into this battle.

Those with a sense of personal honor have an honorable concept of warfare. In this concept, the role of the warrior is to leave his wife and children at home to go do battle with the enemy. He is fighting to protect them from harm. But those who fight not in the cause of honor, but of political ambition, sometimes bring their sons to the battlefield with them.

This is what we find happening among the rebels in Zaire. Children, some as young as eight, are being pressed into battle. That by itself would be deplorable, but the rebels go beyond this, taking advantage of a child's penchant for belief in the fantastic to convince them they are invincible, and cannot be killed.

The rebels promote a pre-existing myth of mystical warriors known as the Mayi-Mayi. Children who are indoctrinated in this belief are taught that wearing a green vine garland with leaves or grass around their heads can confer invisibility. They are prohibited from touching a non-Mayi-Mayi, and are warned not to touch any object picked up off the ground until after sprinkling it with a special powder. Most of all, they are told their belief in the magic must be absolute in order for it to work. This is, of course, the one universal doctrine of everyone teaching an irrational belief system.

A Mayi-Mayi warrior is reputed to be invulnerable to injury in battle. "Look, these are where bullets hit me," says one youngster, pointing out abrasions on his chest. "Here is where a rocket hit my head. You see, the bullets turn to water when they hit me." Remarks like this should demonstrate for all time the utter worthlessness of personal testimony in the pursuit of truth.

"We are training them, but they are already fierce fighters," a rebel officer who identifies himself as Captain Chuck Norris assures us. "Just because they are small does not mean they do not have a reason to fight." But it is the reasons of those who send them off to fight which should be questioned.

The regular rebel soldiers wear new uniforms, and are well-armed. The Mayi-Mayi youth fight with weaponry ranging from machine gun rifles down to lead pipes or slingshots. They wear either tattered old Zairian Army uniforms, or whatever they came with. Most are adorned with rosary beads and other talisman. Some sport an old shower hose worn over the shoulders like a military braid, or a drain plug dangling from the shirt. When asked, they explain these are symbols of the magic water which is part of their initiation ceremony.

These youngsters enthusiastically sing and dance their way into battle, which reportedly rattles the nerves of the enemy troops. The troops whisper darkly of the Mayi-Mayi's proclivity for cannibalizing fallen enemies. Nor is this just more silly superstition on their part. Independent observers have documented cases of these child warriors eating the hearts of their victims, motivated by the belief that in so doing, they are denying their enemy's soul a place in heaven.

One government commander, frustrated with his troop's acceptance of the invulnerability of the Mayi-Mayi, ordered a captured prisoner shot with a rocket grenade in full view of his men. We skeptics typically applaud the testing of paranormal claims, but most would probably draw the line at blowing up a child.

When the rebels go on the offensive, who do you suppose leads the way? The rebel leaders naturally make the logical choice, placing the fighters who cannot be injured or killed in the front, with the regular troops bringing up the rear.

But at this point, one is likely to ask, "Surely some of the Mayi-Mayi get wounded or die in battle. How is this accounted for?" Indeed this does happen. Don't think for a moment that it in any way hinders belief in the magic. Those who are killed or injured, it is explained, did not follow the strict code of the Mayi-Mayi with sufficient diligence. Another possibility offered is "friendly fire", as the magic only protects one from the projectiles of the enemy.

This all reminds me of the Arabic warriors of history who were given drugs, and, while still high, "serviced" by prostitutes. When they came out of their drug-induced daze, it was explained to them that they had temporarily left this world, and had visited Paradise. Evidently Paradise has everything but the rock-and-roll. The men were assured that any fighter who died for the cause was guaranteed a place in Paradise. The result was fearless warriors, eager for martyrdom. So the use of faith in the supernatural for the recruitment and motivation of soldiers is nothing new.

Whenever one embraces an irrational belief system, it makes one easy prey. Prey for those pursuing the quick buck. Those seeking to motivate you toward a political end. And throughout history, in all places, time and time again, those in need of cannon-fodder for their wars of ambition.
I was prompted to write this article after noting that for many space advocates, Mars was the be-all and end-all of space advocacy. Other goals, such as a return to the moon, were being judged solely by their utility in getting us to the red planet. Should we return to the moon, or is that only a needless detour on the road to Mars?

This article also appeared in the Summer 1999 issue of **Space Front** , a publication of the **Space Frontier Foundation**.

#

# Been There, but Have We Really Done That?

### by Mike Combs

######  mikecombs@aol.com

###### Copyright © 1999

Here lately, I've found myself arguing a lot with Martians.

No, that's OK; I assure you it's not a case of my needing to get my lithium dosage adjusted. I'm referring not to the little green guys of mythology, but to perfectly-human Mars colonists. Or more accurately (since the colonization has not yet actually begun), the wannabes. (OK, in all fairness, I must admit to being a wannabe O'Neill settler myself. Yes, I freely confess up front that I'm one of "Gerry's kids".)

Some of my fellow space activists seem to have set their targets squarely, and almost solely, on the planet Mars. I'm not talking about activists who are favorably disposed toward the idea of humans on Mars. Heck, I like the idea too. I only mean the kind of enthusiast that, when you discuss a return to the moon with them, grows impatient, seeming to view moonbases and lunar development as an unnecessary detour on the road to the red planet. Is this view justified?

Some of the arguments used to support this viewpoint are:

**Been there, done that** \- We don't need to go to the moon because we've already gone to the moon. Time to press on to the next destination.

Between 1969 and 1972, the Apollo project landed a dozen men on the lunar surface in six different locations. All of the landing sites were within 26 degrees North and 9 degrees South of the equator due to orbital requirements, and none of them were on the far side due to communications issues. The total surface area of the moon is roughly the same as that of Africa. If extraterrestrials were to briefly land twelve explorers in six scattered locations on the continent, all well north of the equator, could it be said they had in any substantial way explored Africa? What could they have missed? Where lunar exploration is concerned, we have literally only begun to scratch the surface.

Also, a Mars transfer orbit is about 480 times the distance of a lunar transfer orbit, a fact which should shatter the perception that Mars is just the next stop on our space itinerary. It might be advisable to accumulate some additional manned deep space flight experience prior to embarking on a two-orders-of-magnitude-more-difficult journey.

**The moon is dull** \- There's no atmosphere on the moon, and there's no possibility life ever evolved there.

The Martian atmosphere is one percent as dense as ours, while the moon has zero atmosphere (practically speaking). So I suppose some wag could say the difference between the lunar atmosphere and that of Mars is a difference of one percent. But more seriously, the atmosphere of Mars will in no way mitigate the difficulties of providing needed pressurization for humans in comparison to the Moon. While the atmosphere of Mars might be useful for In-Situ Resource Utilization (ISRU), it also creates sandstorms, so one has to take the bad with the good. Deriving useable oxygen from lunar soil is admittedly more complicated and involved than generating it from Martian CO2, but it's certainly not impossible.

As for no possibility life ever evolved on the moon, I submit we do not yet know that life ever evolved on Mars. Some scientific evidence seems to support the idea; some seems to dispute it. The jury is still out, and in the meantime I think it would be a mistake for us to build the justification for the continued human exploration of space on the unsure foundation of Martian microbes. This is one structure we space advocates can't afford to have come crashing down on us in the event there turn out to be no microfossils on Mars to study.

One might have thought the late discovery of ice at the lunar poles would have been the death of the argument that we don't need to return to the moon because we've already studied it, and already know what's there. Who can rule out that other, even more unexpected lunar discoveries lie ahead, given continued exploration? I suspect our moon has many surprises yet to be revealed.

**We don't need to go to the moon in order to go to Mars** \- Going to the moon just to "try out" the technologies needed for Mars exploration will only serve to delay achievement of the final goal.

I won't advocate returning to the moon simply as a trial run for landing on Mars (although some have made a good argument regarding the relative return-trip-times in the event of an emergency). And it's absolutely true we don't need to go to the moon in order to go to Mars. We also didn't have to build a reusable space transportation system, nor an Earth-orbiting space station, in order to land men on the moon, even though space thinkers had advocated these from the very beginning of lunar exploration proposals. And thirty years later, what do we have to show for skipping over these intermediate steps with regard to subsequent lunar development?

"Mars First" proponents sometimes bristle at the comparison to Apollo, but I think it's justified. With Apollo, we decided to forego in-space infrastructure in order to reach the goal more quickly. I'm aware Mars advocates have made enormous strides in terms of reducing the costs of a Mars mission relative to Apollo, and I think ISRU to generate fuel on Mars is a brilliant proposal. But I feel it would be a mistake to proceed to the Red Planet on these alone. We need additional in-space infrastructure.

Consider this: A pound of ore can be lifted from the moon to a high Earth orbit for only 1/20th the energy as from Earth to that same orbit. Thus, any ship built from lunar ores in that orbit will start out with a tremendous advantage over any spacecraft built on Earth, crammed down into the cargo bay of some Earth-to-orbit system, and then rocketed off piecemeal.

A ship for crews journeying to Mars may require both closed-cycle life support systems and artificial (spin) gravity. Both necessitate large spacecraft designs; the former due to buffering considerations, the latter due to Coriolis-effect concerns. If we begin with assets of lunar mining, and high-orbital refining and fabrication available, such huge designs become economically practical. So even if a return to the moon is not a prerequisite, it is certainly an enabler, both for Mars voyages or any other space goal one can name.

**Only Mars has all of the elements needed for a space civilization** \- As the moon is lacking in hydrogen, carbon, and nitrogen, Mars is the place to go to build the future.

One space advocate I was recently debating with stated that the resources of Mars "make the Moon pale in comparison". With the recent discovery of lunar ice, carbon and nitrogen may be the only remaining Martian resources scarce on the moon. (And it's worth pointing out that all of these resources are available in most Earth-approaching asteroids, at the bottom of very shallow gravity wells.)

But there's one overwhelming advantage of the moon's resources over those of Mars: lunar resources are sufficiently close by that their utilization could have returns to the economy of Earth. I think this is vital for getting the space enterprise started in the first place. Martian resources are good for one purpose and one purpose only: to construct habitats to live on Mars. Lunar resources can be used to build habitats to live in High Earth Orbit, as well as Solar Power Satellites (SPS), enormous GEO communication platforms, and even ships for solar system exploration.

### \---

But to be fair to both sides, does the "Back to the Moon" crowd sometimes overstate their case? Sure.

I've sometimes heard the moon advertised for astronomy. While the lack of atmosphere is certainly an advantage over Earth, what is the advantage over High Earth Orbit? We can use the bulk of the moon to shield a radio telescope from the radio noise of Earth, or we can use less than a millimeter thickness of aluminum; either would do the job. "Farside Observatory" has been discussed so much it has almost become like a real place. But "High Earth Orbit Observatory" can look in any direction you like, not just where the moon is presently pointing it. As can orbiting optical telescopes consisting of vast arrays of floating mirrors totaling several city blocks in area. However, the best source of raw materials for building both of these high-orbit observatories will likely be the moon.

Then there are the lunar energy production proposals: Helium-3 and solar. Those fusion reactors do not yet exist even as paper designs, so I would leave that out of immediate consideration. This leaves solar, which, in my opinion, is best done not in a place which is dark 50% of the time, but instead in free orbit. But given the outstanding advantages of using lunar resources for SPS construction (or any other high-orbit enterprise), it still remains that the moon figures prominently in a space-based solution to our global energy needs. And we need that solution up front, if for no other reason than to forever silence the "But what do we get out of space?" crowd.

A stepwise, walk-before-you-run approach including a return to the moon, the establishment of lunar mines, and the use of lunar resources in High Earth Orbit manufacturing facilities will in the long run place us on Mars, or at any other destination in the solar system we may find desirable. And it may even pay for itself along the way, which means it might stand some chance of getting off the ground.

Going to Mars is a noble goal, and is worthwhile from both a scientific discovery and human adventure standpoint. I'm certain we'll walk those red sands someday, and very much hope it happens in my lifetime. But I think our reasons for sometimes being tempted to set our moon aside so we can get on with Going To Mars Real Soon have more to do with romance than with the laws of physics, and with Bradbury than economics.

We space advocates sometimes like to draw an analogy between the settlement of space, and the settlement of the New World. In this comparison, Low Earth Orbit becomes Plymouth Rock, the moon and cislunar space is the eastern seaboard, Mars is the mid-west, and the belt asteroids are those California hills which we all know are made of gold (though now, volatiles are more to our liking). To my mind, going to Mars before we have economically-developed and inhabited the moon and near-Earth spaces is like the Pilgrims landing on Plymouth Rock, quickly building Conestoga wagons, and then immediately pressing on to Oklahoma. First, let's return to Boston (we hardly even got to know the place in that one, brief visit so long ago). First, let's build Philadelphia. The Westward Movement, and even the Gold Rush, will each come in their turn.
Obviously the title of the following article was inspired by the title Robert Zubrin picked for his most famous book: **The Case for Mars**. And to a certain extent this article is certainly an answer to some of the assertions in that book. Zubrin's most recently published book is titled **The Case for Space**. Please know I titled this article well before Zubrin picked that for a book of his (not trying to be a copy-cat, honest).

Would we be better off building settlements on the surface of Mars, or in free space? This article seeks to provide a side-by-side comparison.

This article also appeared in the Fall 1999 issue of **Space Front** , a publication of the **Space Frontier Foundation**.

#

# The Case for Space

### by Mike Combs

###### mikecombs@aol.com

###### Copyright © 1999

Sunlight Available 24x7  
Convenient Access to Zero Gravity  
All Gravitational Options Available  
Living at the Top of a Well  
No Weather, Save What We Make for Ourselves  
Warning! Warning! Meteor Storm!  
Convenient Communication with the Homeworld  
Convenient Travel to the Homeworld  
Making A Living  
A Staging Post for the Belt?  
Room To Grow  
Location Options  
Spreading Interstellar  
Getting What You Need  
Robert Zubrin's Views  
Conclusions

Postscript

From the very beginnings of both science fiction and serious scientific speculation, most concepts for future colonization beyond the Earth have targeted the planet Mars. The reason why is easy to see. Of all the planets in our solar system, it's the one most like Earth.

But starting in 1969, Princeton University's Professor Gerard O'Neill began looking in a different direction: toward artificial habitats constructed in orbit from materials already in space. He had started by asking the question, "Is the surface of the Earth really the right place for an expanding technological civilization?" Some study seemed to indicate the answer was "No". Calculations revealed that orbital habitats could be surprisingly large and Earth-like, and would have many advantages over any planetary home.

O'Neill's findings made us realize there was an unspoken and unquestioned assumption underlying the logic that pointed toward Mars: In order to create colonies beyond Earth, we must first find a planet on which to build them.

In the years since the initial enthusiasm following the publication of O'Neill's "The High Frontier", interest in the concept of space colonies seems to have abated, while interest in Mars settlement and ultimate terraformation seems to be at a peak. Viewed from the High Frontier perspective, the construction of orbital habitats instead of Mars settlements would still seem to have better returns on shorter time scales, much greater long-term benefits, and numerous other advantages.

Before we begin, it should be noted that many of the benefits cited for Mars colonization (e.g. not keeping all of our eggs in one planetary basket, stimulation to technical advancement, multiplication of human opportunities and potentials for freedom, etc.) are in fact equally good arguments for either settlements on Mars or in orbit, and thus will be outside the scope of this article.

Also, when comparing the relative merits of orbital space versus the surface of Mars for settlement, such comparisons should only be made between proposals with similar returns. Some have compared Dr. Robert Zubrin's Mars Direct strategy with Gerard O'Neill's High Frontier proposals. Mars Direct should only be compared with a program placing an equivalent number of people in High Earth Orbit, along with an equivalent amount of infrastructure geared toward supporting future settlement plans. Other valid comparisons would be: comparing the construction of the first Island One or Stanford Torus habitat with the construction of the first domed community on Mars large enough to independently support a population of 10,000, and comparing the terraformation of Mars with an orbital settlement program resulting in the creation of habitats sufficient to equal the land area of Mars.

**Sunlight Available 24x7**

The reason we've not been able to convert our Earthly economy over to solar energy is that it's intermittent here on the surface. The sun is blocked every night, and is filtered by clouds. In a sufficiently high orbit, an O'Neill colony will be in sunlight around 99% of the time. This means solar energy can be relied upon not only for life-support and agriculture, but also for electrical utilities and process heating for industrial operations such as the smelting of ore. On Mars, as on any celestial body, solar energy will be unavailable half the time. We don't tend to see this as a disadvantage because it's the present situation here on Earth, and we're used to it. But locating in orbit opens up the possibility of a vast civilization powered by cheap, clean, plentiful, continuous solar power. And given the direct relationship between energy usage and living standard, this space civilization can be expected to exceed both Mars and Earth in this respect.

Nuclear fission reactors are a possibility for Mars, but have become politically unpalatable. Nuclear fusion is presently not possible, and given its history, probably cannot be counted upon in the near term.

Constant access to sunlight means the climate of an O'Neill settlement can be whatever we choose.

It's not presently known which of our food crops (if any) can tolerate 24-hour-a-day sunlight. But if some or all should prove able to take advantage of this, then unceasing sunlight will be an option for the food growing areas of space habitats.

**Convenient Access to Zero Gravity**

Aside from the obvious entertainment possibilities, zero gravity enables the construction of vast, gossamer-thin space mirrors several miles across. Such mirrors can enable Earth-like conditions inside of orbital habitats, and concentrating mirrors can provide prodigious amounts of heat for ore processing. Such flimsy mirrors would not be practical on the surface of Mars due to the presence of gravity and winds.

By the same token, heat radiators for habitats can have both enormous area and very thin construction. Getting rid of waste heat is admittedly more difficult in space than in a planetary environment, but the superior kind of heat radiators which it will be possible to construct in zero G should provide a solution to this problem.

**All Gravitational Options Available**

Orbital habitats will simulate gravity by rotation. This means complete control over the gravitational environment. A full one-G can easily be provided if it should happen that nothing less than this will maintain normal muscular physique. If 1/3 G does turn out to be acceptable, we can have that too.

The unfortunate situation with planets is that you have to take the gravity you get, and it's frequently the wrong amount. It's possible children born on Mars may not be able to visit Earth. At best, they certainly couldn't visit Earth without considerable discomfort. Children born in an O'Neill habitat under a full one-G of centrifugal force shouldn't experience any problems in this regard.

Rotating a habitat on the surface of Mars to bring the gravity up to one G is probably not an option due to excessive loading on the bearings, and air drag. But in zero G and vacuum, making a habitat spin and keeping it spinning are much easier to accomplish.

Thus, in terms of both the levels of sunlight and gravity, orbital settlements may provide a much more Earth-like environment than even a completely-terraformed Mars.

**Living at the Top of a Well**

We here on the Earth are the "gravitationally disadvantaged", living as we are at the bottom of a steep gravity well. It's the reason space flight is so expensive and difficult for us. The gravity well of Mars is less deep than that of Earth, but it's still much deeper than that of the Moon, and enormous compared to that of an asteroid. This is why mining asteroids to bring materials back to Earth is just barely a possibility for the future, whereas Mars mining would probably not be able to compete due to the tariff which gravity imposes.

Settlers living near the top of Earth's gravity well will be ideally positioned for departures to Mars, or any other destination elsewhere in space.

**No Weather, Save What We Make for Ourselves**

Planets with atmospheres have weather, and we must consider it when designing and building structures. On Mars, there are globe encircling dust storms. Photographs from the Mars Global Surveyor have recently been released showing the shadows of 5-mile-high dust devils.

In orbit, coasting silently in vacuum, there's no weather. On the other hand, inside sufficiently large habitats, it should be possible to create our own natural weather, complete with cloudscapes and rainstorms. But since we'll be making the weather, we'll be in control of it. Thus there's every reason to expect the climate in any man-made habitat to be vastly superior to all but the most desirable climates found on Earth.

Some type of weather control might be possible inside of domed enclosures on Mars. But a thoroughly terraformed Mars will have weather systems beyond human control. Again, we tend not to recognize this as a liability, because it's the situation we're already well used to here on Earth.

**Warning! Warning! Meteor Storm!**

One widely perceived advantage of Martian settlements over orbital ones is that they'll have the atmosphere of Mars to protect them from meteors. But it turns out the danger of meteor strikes in space is much more modest than "Lost in Space" has led us to believe. O'Neill estimated his Island Three model (biggest cross-sectional area means greatest risk) might expect to get hit by a one ton meteor once every million years. One should expect a meteor the weight of a tennis ball to come along about every three years. Even if it did penetrate the hull, such a puncture would mean a routine, minor repair, not an emergency.

Some express a concern about man-made orbital debris, which is in fact becoming a serious problem for space stations. But most of this debris is in Low Earth Orbit, with some around Geosynchronous Earth Orbit. The nearest O'Neill habitats would orbit far higher; at least halfway to lunar orbit.

**Convenient Communication with the Homeworld**

The signal delay time due to the speed of light for High Earth Orbit is less than a second. Apollo astronauts were able to communicate (albeit with slight awkwardness) as far away as the Moon. The speed of light delay between Earth and Mars ranges from a bit over 4 minutes to 21 minutes. This obviously makes real-time conversations impossible. Martians would have to settle for "video letters". But much more significantly, this time delay makes the use of telepresence from Earth impossible on Mars. On the other hand, mining operations on the moon, and refining and fabrication operations in High Earth Orbit might get a boost at the onset by extensive teleoperation, reducing the initial manpower requirements. Being able to prime the industrial pump remotely (should advanced telepresence technologies become available) would certainly have significant advantages.

**Convenient Travel to the Homeworld**

Most NASA estimates for the trip time to Mars place it at eight to ten months. Making various estimates regarding advanced space drives, this can be brought down by several months. For example, Robert Zubrin proposes a nuclear engine-augmented heavy lift launch vehicle which could transport colonists to Mars in seven months. The political acceptability of launching nuclear engines is presently uncertain (whether or not such fears are scientifically justifiable is largely irrelevant).

Space habitats in an orbit roughly halfway to the moon will have travel times from Earth of less than a week even with present chemical rockets. A Closed Ecology Life Support System (CELSS) may be required for journeys to Mars, but should be unnecessary for travel to and from habitats orbiting the Earth.

**Making a Living**

Although a Martian economy may someday become possible, it seems likely to remain a local economy. There seem to be no marketable products that Martians could sell to Earth which would be worth lifting out of the gravity well of Mars. Martians might sell real estate to Earthlings, provided there was some compelling reason to want to live there, and living conditions on Mars were reasonably pleasant.

The residents of orbital colonies, in addition to building additional colonies for sale to immigrants from Earth, would certainly also be constructing Solar Power Satellites (SPS) for sale to countries in need of additional electrical capacity, and gigantic communication platforms for geosynchronous orbit. Admittedly, one doesn't need large, Earth-like habitats in order to use space resources to create these products, but having a permanent workforce nearby certainly helps. Provided that Earth was still footing the bill for continued space exploration at this point, we could even add manned exploratory ships for travel elsewhere in the Solar System to the list of products which would help balance the sheets.

All of the above would represent returns to the economy of Earth. However dedicated Mars enthusiasts may be to creating a self-sustaining Martian economy, it's difficult to see how the process can get started in the first place without expectations of a return on Earth-originated investments. SPS and advanced communication platforms are products marketable to Earth. By the same token, unlike the natural resources of Mars, the resources of the Moon and Near Earth Objects (NEO's) are sufficiently close by that their usage could have returns to the terrestrial economy.

An earlier argument was made that Mars was the place to go to because, unlike the Moon, it has plentiful supplies of hydrogen, carbon, and nitrogen. The recent discovery of ice at the lunar poles by the Lunar Prospector probe has blunted this argument somewhat. It's also worth mentioning that all the elements we need are available in most Near Earth Asteroids.

**A Staging Post for the Belt?**

It's sometimes argued that communities on Mars are necessary to support further expeditions out into the asteroid belt (which is expected to be a treasure trove of needed resources). It may be that this perception comes from the Earth-bound truism that being closer to a place makes it easier to get to. But in space, distance does not count nearly so much as delta V. Inhabitants on Mars would be closer to the Belt than we are, but they'll be at the bottom of a gravity well. In terms of delta V, residents of a habitat in a high enough Earth orbit will already be half-way to the belt, and can use low-thrust, high-efficiency drives the entire way.

Distance can be a significant factor in space travel with regard to travel times, especially in relation to life-support system requirements. In fact, this can legitimately be used to argue that going to Mars is still a more "difficult" journey than returning to the Moon, even if aerobraking and in-situ fuel production combine to make it "easier" to get to Mars from a strictly fuel-oriented standpoint. But one imagines by the time closed-ecology habitats are circling the Earth, a CELSS for a trip to the asteroid belt would be available.

It seems likely that only NEO's will be utilized in the near term, with Main Belt asteroids being used later, as humanity spreads outward from Earth. Even after the NEO's are exhausted, it'll always be possible to build new space habitats in the Belt itself, close to the source of raw materials.

From several standpoints, settlers in orbital space will quite literally be in a better position to exploit asteroids than anyone on a planetary surface.

**Room to Grow**

A completely terraformed Mars would give us approximately the land area of the Earth. Earth is much bigger, but is mostly covered with oceans. If oceans are desired on Mars (or if they turn out to be necessary to sustain an Earth-like global climate), then deduct accordingly.

We earlier stated that only an orbital settlement construction program which resulted in new land area equal to that offered by Mars should be compared to a Mars terraforming project. Is it really possible to build this many space communities? Can they be built on a time scale competitive with terraforming?

Let's do some simple calculations. The 1975 NASA-Ames study resulted in a space habitat design known as the Stanford Torus. It was designed to provide 670,000 square meters of living space. The surface area of Mars is around 145 million square kilometers. Let's assume no Martian oceans, and ignore the fact that even on a totally Earth-like Mars the Polar Regions would certainly remain inhospitable. In this comparison, Mars roughly equals 216 million Stanford Torus models.

NASA's study indicated that the first independent orbital habitat could be completed 22 years after initiation of the program, and that a habitat could build a duplicate habitat in 2 years. Let's conservatively assume it'll take 50 years to build the first one, and assign 5 years to the doubling time. We'll also ignore the possibility that the more space communities we build, the better (and faster) at it we'll get, as well as the efficiencies which might be later gained by building smaller numbers of larger habitats with greater land area.

By the time we had achieved 28 doublings, we would have begun to exceed the total land area of Mars. By the pessimistic timetable above, this would take 190 years. (Please note it's not being predicted that this will indeed be the actual growth rate seen, merely that this is the maximum rate allowed by technological constraints.) It's the rare terraforming proposal that's optimistic enough to promise a Mars made over in Earth's image in less than two centuries. Another important point is that near the beginning of the O'Neill settlement construction program, the workforce begins enjoying living conditions that may be even more Earth-like than those possible on Mars only at the very end of the terraforming effort.

Lest it be argued there's not enough raw material available to build this many orbital settlements, the resources of the asteroid Ceres alone would allow us to do this five hundred times over. Space habitats represent an incredible economy of mass in comparison to planets.

O'Neill was interested in shattering the limits to growth which were widely (if somewhat incorrectly) perceived in the 1960's. He once calculated that even if we limited ourselves to the resources of the asteroid belt (merely the most convenient source of materials, and not the only one), we could still build, in the form of orbital habitats, over 3,000 times the livable surface area of the Earth.

Thus, Mars holds out the promise of becoming home to a planetary civilization which might rival that of Earth. Orbital colonies can form a space-based civilization that far surpasses Earth's in both size and diversity.

**Location Options**

Martian settlements would be a home on Mars. Orbital settlements could be homes anywhere in the solar system (and perhaps even beyond) that we care to be, as long as we're not frequently eclipsed by a planet. One can locate further from the sun simply by making the habitat mirrors bigger, and slightly concave, so as to concentrate the sunlight up to Earthly levels. Even the apparent diameter of the sun in the sky would be the same as we're presently used to. Habitat orbits beyond Pluto are not out of the question. Unfortunately, this same solution cannot be used to raise the sunlight levels for colonies on the surface of Mars, due to the impracticality of such flimsy mirrors in an environment of gravity and weather.

Some space-based societies will doubtless elect to remain close to Earth, enjoying both real-time communication with, and speedy travel to, the homeworld. Other groups, wishing to remain forever apart from Earth-centered civilization, could choose to become far more remote than even Martians ever could.

Significantly, orbital territories would be mobile. This is yet another clear advantage that would scarcely even occur to us Earth-bound folk, since it's an option we've never enjoyed here. If an orbital community found itself next door to another that it simply couldn't stand, there would be a solution short of "ethnic cleansing". They could simply attach engines, and move.

**Spreading Interstellar**

At this point we cast our gaze even further afield, toward the distant stars. It's true the perfection of our terraforming skills on Mars might ultimately make the settlement of selected planets in certain other solar systems possible. But O'Neill habitats make _every_ solar system a candidate for settlement, regardless of the presence or absence of suitable planets, or indeed any planets at all. Many solar systems may lack terrestrial planets due to gravitational disruptions from superjovian planets or multiple suns. But from our present understanding of the dynamics of solar system formation, systems without asteroids or comets seem unlikely.

**Getting What You Need**

Thus far the discussion may seem a little one-sided. Aren't there any criteria by which building settlements on Mars may have advantages over building them in free space? There's one I'm aware of. The High Frontier scenario is dependent on the retrieval of resources to High Earth Orbit, either from the lunar surface or from NEO's. The cost of transporting these raw materials must be factored into the cost of establishing space habitats. On Mars, the ores needed are literally underfoot. Both carbon and oxygen can be generated from the atmosphere using technology already demonstrated in the laboratory. The Martian atmosphere, while thin, is accessible anywhere on the planet. This is a significant advantage.

There are two questions then that must be answered. Number one is: Are the costs of transporting the needed resources to Earth orbit so large that they exceed the additional expenses of establishing colonies at the much more distant location of Mars? The answer may not be presently clear. Mass-driver technology holds out the promise of significant cost savings in the area of resource retrieval. A mass-driver erected on the lunar surface can act as a catapult for launching ores into space for pennies a pound. Less well known, a mass-driver can also function as a highly efficient reaction engine for an asteroid ore transporter. Such an engine would require nothing other than solar energy for power, and dirt for reaction mass. However, while demonstration models of mass-drivers have validated that the desired payload accelerations are possible, the required speeds have not yet been demonstrated.

The other question is: Even if it should happen that ore transportation costs _were_ to make orbital settlements somewhat more expensive than Mars settlements, would the difference completely overwhelm the many advantages of orbital space we've discussed?

**Robert Zubrin's Views**

Since the passing of Gerard O'Neill in 1992, Dr. Robert Zubrin, founder of Pioneer Astronautics and author of "The Case for Mars" has emerged as the foremost public advocate of colonization beyond the Earth (the only other possible contender might be Marshall Savage). Zubrin has designed strategies for voyaging to Mars that are much less expensive than any previous proposals, and believes such journeys will lay the foundation for a vast future Martian civilization. He's been quoted as referring to O'Neill's concepts for constructing orbital habitats and Solar Power Satellites from space resources as "absurd".

In his paper "The Economic Viability of Mars Colonization", Zubrin makes the following remark:

But the biggest problem with the Moon, as with all other airless planetary bodies and proposed artificial free-space colonies (such as those proposed by Gerard O'Neill) is that sunlight is not available in a form useful for growing crops. This is an extremely important point and it is not well understood.

This point is not only "not well understood", but is quite surprising to one viewing things from the High Frontier perspective, which holds that solar energy is more available in High Earth Orbit than on any planetary body. But Zubrin proceeds to explain his logic. He reminds us that crops must be protected from space radiation, and calculates this would require glass walls 10 cm thick, which is assumed to be "prohibitively expensive". Then, apparently aware that this is in fact not the solution proposed by O'Neill, he goes on to say:

Use of reflectors and other light-channeling devices would not solve this problem, as the reflector areas would have to be enormous, essentially equal in area to the crop domains, creating preposterous engineering problems if any significant acreage is to be illuminated.

What these preposterous engineering problems specifically are, he does not indicate. It's true we're not normally accustomed to discussing the construction of mirrors miles across. But we normally view things from the perspective of the Earth's surface, where such mirrors would have to support their own weight, and withstand winds and other weather conditions. Space mirrors will face no such requirements.

In this same paper, Zubrin confesses that, following several decades of atmospheric density buildup, the normal processes of photosynthesis might take a millennia to add sufficient oxygen to the Martian atmosphere to make it breathable. Thus, he anticipates that more high-tech methods will be employed to speed up this process. One method he discusses is nanotechnology, which he estimates might cut the time down to a mere thirty years.

Zubrin chooses to consider mirrors the size of cities preposterous. A proponent of High Frontier concepts might similarly choose to view self-replicating machines the size of molecules as preposterous. So is that it? Is this debate ultimately reduced to dueling incredulities? Perhaps. But this can be said: The technology to create miles-scale mirrors in zero gravity and vacuum would certainly seem to be more in hand than molecular nanotechnology.

Some other methods Zubrin cites to possibly speed up terraforming efforts are terawatt-sized fusion reactors, space-based lasers, and space-based reflectors; the latter of which is the very technology which he will not allow may make independent orbital communities possible.

In his paper on the economic viability of Mars, Zubrin foresees a triangle trade amongst Earth, Mars, and the Asteroid Belt. But this interplanetary economy is predicated on the assumption that asteroid miners will be unable to grow their own foodstuff. This proceeds from Zubrin's dismissal of the concept of space mirrors as big as cornfields. If the High Frontier concept should prove correct, asteroid miners can live permanently in the belt in Earth-like habitats perfectly capable of growing their own crops. In such a situation, Mars would seem to have little to sell them.

**Conclusions**

Gerard O'Neill's findings prompted Isaac Asimov to coin a new phrase: "planetary chauvinism". This refers to our natural tendency to assume activities elsewhere in space are best done on the surface of a planet. But as seen here, almost any way you look at it, planets are inconvenient things.

When making serious proposals for colonization beyond the Earth, we're obliged to set aside the romance of Burroughs and Bradbury, and ask what strategies return the greatest benefits most quickly for the least investment.

To my mind, space is the place.

### * * *

**Postscript:**

After publication of the above article, I started a thread on the Usenet newsgroup sci.space.policy named  Which is better, Mars settlements or space settlements? in which I invited counter-points to the above. Discussion continued in another thread entitled  Why Mars Now?

Firstly, one poster made the case that on a terraformed Mars, the ecology would be "wilder". It's doubtless true that the ecology in an orbital habitat will have to be much more closely managed than any planetary ecology. And it may very well be that orbital settlements will for a very long time remain too "park-like" for some folk's tastes.

Two others saw advantages for Mars where incremental expansion of living space was concerned. One raised the possibility of a pressurized brickwork habitat for Mars made out of indigenous materials. Making bricks is certainly a simpler materials process than making steel plate, but I'm uncertain about the relative levels of labor involved. If we care to make it a comparison between orbital settlements and terraforming Mars, I think orbital settlements are the obvious winners in the incremental expansion category.

One poster, after urging that all debate on this subject cease, said he would only state one advantage of Mars: Mars has more resources. While Mars certainly _masses_ more than the belt or even the moon, this argument doesn't consider the issues of ease of access, or costs of exporting resources.

One of the more frequent posters to the threads stated that Mars is more popular, and expressed the opinion this single fact overrides all other considerations.

Perhaps one of the best points made by someone on the newsgroups was that I was being somewhat unfair in my depiction of Robert Zubrin's views. It was pointed out that the section of "The Case for Mars" from which I pulled the quote concerning the impracticality of large space mirrors was from the near-term-future section of the book. The reference to using orbital mirrors to aid in Mars terraforming efforts was from a later section dealing with a much more distant future (one in which the engineering difficulties of enormous space mirrors had presumably been worked out).

It was almost certainly wrong of me to leave the reader with the impression that Zubrin's points are inconsistent. In fact, in his later book, "Entering Space", Zubrin, while arguing forcefully that space settlements will never be built in support of SPS, later says that a Type III (interstellar) civilization will build orbital habitats in asteroids and Oort cloud objects "with many of the features envisioned by O'Neill".

But I think the point remains that Zubrin mentions High Frontier proposals only to compare them to Mars Direct (a much more modest, and hence realizable, near-term goal). When discussing much more future eras, High Frontier gets little or no mention, and no comparison is ever made with proposed Mars terraforming efforts. Humanity is assumed to still be working the Martian surface in an attempt to make it more Earthlike. This seems to assume that no better alternative will be available even then.

I don't think it's incorrect to say that more than one reader of Zubrin has come away with an impression that orbital habitats are forever impossible, given his stressing of the engineering difficulties over the short term, and his nearly exclusive discussion of planetary engineering for later eras. The quote " _...human beings will never settle Earth orbit, because there is nothing there to settle_ " seems open-ended, and without qualification with regard to time lines.

I would agree that High Frontier should not be proposed as an alternative to Mars Direct, since (as stated near the beginning of this article) they are not comparable projects. I still see the way clear to propose space settlements as an alternative to the large scale settlement and/or terraformation of Mars, as by the time we've gained the technical experience needed to re-engineer other worlds, there could be no doubt we could also engineer large orbital structures as well.
This article discusses the use of lunar resources in nearby space, and the feasibility of lunar mass drivers.

The article appeared in the Summer 2000 issue of **Space Front** , a publication of the **Space Frontier Foundation** , and I also had the honor of presenting it at the 2004 **International Space Development Conference**.

#

# Building Dreams from Moondust

### by Mike Combs

######  mikecombs@aol.com

###### Copyright © 2000

Certainly many early space thinkers have contemplated use of the moon's resources in proposed lunar colonization programs. But probably the first to consider use of lunar materials for the construction of a wide variety of useful structures throughout cislunar space was the Princeton University physicist Gerard K. O'Neill.

After surprising himself with calculations indicating how large an Earthlike space habitat could be built, the next question was: From what do we build these high-orbiting settlements? Lifting construction material from the Earth's surface could immediately be ruled out. Even assuming the lift cost reductions then being promised by NASA for their proposed new Space Shuttle (can you remember those days?), sending the parts up from Earth for even one of the more modest of O'Neill's designs would overwhelm the most extravagant budget imaginable.

But then O'Neill made a simple calculation. The amount of energy needed to lift a kilogram of material from the surface of the moon into a High Earth Orbit (HEO) is about 1/20th what is needed to lift it from Earth to that same orbit. This fact points to our moon as the source of the raw materials needed to settle orbital space.

What is there to mine on the moon? From Apollo, we know ordinary lunar soil consists of:

40% Oxygen  
20% Silicon  
12% Aluminum  
4-10% Iron  
6% Titanium  
3-6% Magnesium

Oxygen (obviously useful for breathing) is also 86% the weight of both water and rocket fuel. The silicon can go into glass and solar cells. The metals are useful for structural materials. Aluminum and titanium are valued by the aerospace industry for their combination of strength and light weight. Titanium, additionally, is a good high-temperature metal.

O'Neill, through his Space Studies Institute (SSI), also sponsored research toward creating fiberglass, ceramics, and cement from lunar materials.

It seemed that over 99% of the raw material needed to build a space habitat could be derived from lunar resources, with no need to lift it out of the Earth's much steeper gravity well. Additional research sponsored by SSI soon demonstrated that similar percentages held for Solar Power Satellites (SPS) optimized for use of lunar materials. The main point weighing against SPS had always been the enormous launch costs. Here now were two products which could greatly benefit from use of lunar resources: An environmentally benign source of constantly renewing electrical power potentially worth hundreds of billions of dollars in the global marketplace, and habitats providing a high standard of living for the workers constructing these energy collectors. Additional products could include enormous geostationary communication platforms, and large spacecraft for solar system exploration.

Later, Near-Earth-Objects (NEO's) were also proposed as sources of raw materials for space construction. Some of these Earth approaching asteroids have round trip delta-V's which compare very favorably with that of the moon. Some additional advantages of NEO's are availability of a wider variety of materials (including volatiles scarce on the moon), and even shallower gravity wells.

But the moon will always retain advantages of its own. Most relate to its proximity to Earth. These include: more frequent launch windows, much shorter flight times, and a radio signal delay time of only a bit over a second (presenting the possibility of teleoperations from Earth, thus reducing initial manpower requirements).

I once entered into a debate with a fellow space advocate after he stated that the resources of Mars "make the Moon pale in comparison". This was in reference to the fact that water, carbon, and nitrogen are generally more available on Mars than on the moon. The discovery by the Lunar Prospector Probe of water ice at the poles of the moon has weakened this argument, at least to a certain extent. And from an energy of retrieval standpoint, asteroids will always be better sources of hydrogen, carbon, and nitrogen than Mars due to the relative steepness of the Martian gravity well.

One factor which should engage our enthusiasm for the moon's resources more highly than for those of Mars is that lunar resources are sufficiently nearby that their utilization could have returns to the terrestrial economy. Surely this is vital for getting the space enterprise off the ground, given that every investor currently in existence lives on the planet Earth. The usefulness of Martian resources for the purpose of constructing habitats for living on Mars is indisputable. However, lunar resources can be used to build habitats for living in High Earth Orbit, as well as SPS, enormous communication platforms in Geosynchronous Earth Orbit (GEO), and even roomy ships for journeying to Mars. These are all products marketable to Earth, as opposed to hypothetical future Martian investors. Mars will never be in as good a position for export as the moon due to the combination of its greater distance and steeper gravity well. Export is vital for balance of trade, and hence economic viability.

When Prospector detected water ice at the lunar poles, the usefulness of this water for lunar surface operations was obvious to everyone. What few realized, however, was that even for a water (or rocket fuel) market in Low Earth Orbit, the energy needed for supply from the lunar surface is still less than for lifting it up from Earth. The distance involved is much greater, but in terms of delta-V, the moon is a better source.

In addition to having a shallow gravity well, the moon is also airless. This opens the possibility of electromagnetically launching lunar material horizontally off the surface and into space. O'Neill began building models of a device he named the mass driver. It was essentially a stretched-out linear motor or electromagnetic catapult with recirculating "buckets". The third model built had the same diameter as what had been proposed for the moon. Accelerations of 1,800 gravities were achieved with off-the-shelf-parts.

But Mark Prado, webmaster of the PERMANENT website, thinks SSI's reliance on the mass driver for launching lunar ores into space may be a mistake. PERMANENT is a proposal for the use of lunar and asteroidal resources for space construction projects. As a physicist who has worked on electromagnetic launchers, Prado says he personally has a great deal of confidence in the mass driver concept. However, he fears business leaders may be leery of it as an unverified technology.

Among some space advocates, there is even greater pessimism regarding the lunar mass driver proposal. I once found myself in a debate on a couple of the space-oriented Usenet newsgroups with some folks who insisted a mass driver could never achieve lunar escape velocity (2.4 km/sec). On the one hand, I had Marshall Savage describing future space-based mass drivers hundreds of billions of kilometers long, capable of accelerating multi-ton starships to near lightspeed. On the other, I had these fellows expressing doubts over a proposed lunar mass driver 160 meters long and about the diameter of a dinner plate, capable of launching softball sized spheres of sintered soil to lunar escape speed. Personally, my incredulity border lay somewhere in between.

One of the debaters sent me a detailed technical explanation of his doubts. The issue he raised involved the switching speed of the coils, which was a function of their inductance/capacitance. Such considerations, it was said, would forever limit mass drivers to velocities below what was needed.

At first his explanation depressed me, because it made sense to me. Then it occurred the implication seemed to be that Gerard O'Neill, a physicist with Princeton's Institute for Advanced Study (the same place Einstein worked) and inventor of the colliding beam storage ring, had negligently overlooked a principle of electricity which I learned in my first or second year of college. Not to mention the many electrical engineers and graduate students who worked on mass driver models alongside him.

I turned to SSI, and was referred to Dr. Les Snively, who worked with O'Neill on Mass Driver Model Three. He stated that the coil switching limitation cited as a concern was in fact an implicit part of their computer models. He also mentioned a strategy O'Neill had devised to overcome it: using greater numbers of single-turn coils at the later, highest speed portions of the accelerator.

It turned out that one reason for the state of pessimism regarding mass drivers was the unfulfilled promises of a coil gun developed by Bill Cowan at Sandia Labs. The goal had been an Earth-to-space launcher, but the velocities predicted by computer models turned out to be elusive. It was generally agreed that this failure "poisoned the well" for additional funding of high speed launchers based on similar (and sometimes dissimilar) technologies.

One can point to significant technical differences between the O'Neill mass driver design, and the Cowan coil gun design. Whether they add up to the difference between a workable and an unworkable approach may not be clear. I'm not aware that Cowan's design ever used the single-turn coil solution suggested by O'Neill. Certainly the operating conditions and design goals were different (for example, launching through vacuum vs. launching through the Earth's atmosphere).

I finally decided that people were essentially saying, "We know the lunar mass driver won't work, because it reminds me of this other technology which was a disappointment". If it's truly a case of pronouncing that the apple's gone bad because the orange is rotten, then perhaps we should not write off the lunar mass driver just yet. For myself, I no longer consider mass drivers a "demonstrated" technology, despite the demonstration of the accelerations required. But neither do I rule them out.

Even if moon-based mass drivers remain forever impossible, other means for economically lifting lunar resources into space may be feasible. A "skyhook" or space elevator for the moon is certainly a less difficult technical challenge than one for the Earth, and may even be possible with existing materials. Whereas construction of an Earth skyhook would begin in GEO, the lunar skyhook would start at the L-1 point between the Earth and the moon. If one end is extended to the lunar surface, the Earthward end would reach sufficiently far into the terrestrial gravity well that payloads released from there would end up in an elliptical Earth orbit. Like the mass driver, such a structure would enable transportation of resources off the lunar surface using electricity rather than rocketry. And the electrical costs would be trivial.

Thus it is possible that in our future, space may be filled with clean, inexhaustible power generators, vast communication platforms enabling ubiquitous wrist communicators, giant ships for exploration of the planets, and even orbiting extensions of life's ecological range; all manufactured from the common, powdery gray dust of our nearest neighbor in space.
I have a particular interest in what SF author Isaac Asimov called "planetary chauvinism". To what extent does this tendency bias our thinking when considering space projects? This article seeks to illustrate this bias with specific examples.

#

# Somewhere Else Entirely

### by Mike Combs

###### mikecombs@aol.com

###### Copyright © 2004

In the 1970's, Princeton physicist Gerard O'Neill began a line of research which came to an unexpected conclusion. Alarmed by the then-prevalent talk about "limits to growth", he started looking at the prospects for the expansion of human society beyond the Earth. Contrary to the expectations left to us by science fiction, O'Neill concluded that the most significant part of our future beyond the homeworld did not lay on the surfaces of other planets. He asserted that conditions on planetary surfaces were less-than-ideal for continued expansion of our technological civilization, and felt that artificial habitats in free orbit would have  numerous advantages over the more conventional, planet-bound concepts for extraterrestrial colonization.

But in the years since the stir in the space community caused by O'Neill's counter-intuitive conclusions, we've seen the planetary paradigm largely regain its former monopoly on our thinking regarding the future of the human race beyond Earth. At present, the planet Mars holds sway over most space advocate's dreams of a second home for humanity. Is it true (as many seem to take for granted) that in the years since publication of O'Neill's "The High Frontier", newer information has rendered this particular vision less practical, or the Mars colonization dream more practical? Or are there no reasons for this shift in view other than planetary chauvinism?

"Planetary chauvinism" was a phrase coined by Isaac Asimov. He used it to refer to our natural tendency to assume that most activities are better done on planetary (or lunar) surfaces than in orbital space.

I'm active on several space-oriented newsgroups, forums, and maillists. I'm not terribly qualified to throw out opinions on single-stage vs. two-stage-to-orbit, air breathing engines vs. rockets, or NASA vs. private industry. Those discussions I follow, but I don't have much to contribute. But I do have one specialized interest, and it's planetary chauvinism. I tend to speak up when I think I'm detecting a whiff of it in a particular proposal. It's made for some interesting, frustrating, and occasionally funny exchanges.

On two different occasions, I've heard someone advocate a particular kind of manufacturing facility on the moon, creating end-products for use elsewhere. Being well-versed in the NASA studies on space manufacturing from lunar resources, I was aware that their recommendation was to concentrate industrial activity in High Earth Orbit (HEO) where there was continuous access to solar power. Those studies recommended lunar surface manufacturing for only one class of products: those whose end use was on the lunar surface.

So I would ask, "Why not place the manufacturing facility in HEO?" to be told that this "just wasn't practical".

"Why not?"

"Because you need a stable platform for major industrial operations."

"What does this mean, 'stable platform'?"

"Well... suppose you had this big stamping press, continuously hammering away in the same direction day in and out. After a while it would disturb the orbit of the space facility."

These kinds of assertions from people make me wonder how much of their childhood was spent pulling themselves around in a wagon. I asked one of them why we hadn't retired those old-fashioned rocket engines to the junk heap in favor of electric-powered pile drivers hammering away at the interior noses of inter-orbital space craft. While I never got an answer to that particular question, the arguer asserted he had seen a TV documentary which said it was possible for astronauts to disturb the orbit of the Space Shuttle by bumping into its interior cabin walls.

The shuttle has sometimes engaged in experiments where even the minutest disturbances in the _orientation_ of the orbiter can be detrimental to results (such as Earth-scanning radars or astronomical observations). I suspected a confusion between "orientation" and "orbit", either on the part of the debater or the documentary itself. But to my horror, another debater (by all accounts a physics PhD) agreed that astronauts inside a space craft could indeed change its orbit by bouncing off its walls.

That same PhD had earlier (and somewhat enigmatically) declared, "The moon is the port of entry into Earth". When we asked what exactly he meant by that, he said he'd have to think about it a while and get back to us (there could hardly be a clearer signal of the ad-hoc reasoning process at work).

When his explanation came, it was this: In the future there will be asteroid mining. Both raw materials and semi-finished goods will be sent back to Earth. (High Frontier thinkers tend to be skeptical of the economics of bringing space resources down to Earth, but let's let him have this point.) Before final delivery, these cargoes will need to be stored. This will happen in vast warehouses on the moon.

I wasn't even the first on the forum to ask him, "Why spend all the money needed to descend and then ascend the lunar gravity well when instead we could just skip the moon and house all this material in HEO?"

We couldn't do this, he explained, because unloading this much material into an orbital facility would disturb its orbit.

I explained that orbital rendezvous was synonymous with matching orbits, that final closing maneuvers could be as gentle as we had patience for, and asserted that the only way payloads entering or leaving this facility would significantly disturb its orbit was if we used some kind of electromagnetic system to decelerate rapidly incoming cargo or rapidly accelerate outgoing. I then suggested we simply not use our storage warehouse as either a catcher's mitt or cannon. But this wasn't what he was talking about. He was talking about the fact that placing this much cargo inside the orbital facility would change its center of gravity, and thus its orbit. And he had any number of bewildering equations to show us he was right.

Now this wasn't so much a wrong answer as it was a case of straining at a gnat while swallowing a camel. The center of gravity issue he raised might amount to a few meters in an orbit ranging over many thousands of kilometers. The amount of propellant needed to brake several thousand tons of raw materials or semi-finished goods into lunar orbit, de-orbit, hover, soft-land, and then later reverse the entire process he did not consider an especially-great problem. The amount for a brief, minor station-keeping burn on an orbital facility: a show-stopper. Only the moon could provide a sufficiently stable platform to take on several thousand tons of cargo.

I finally decided that all of his equations, arguments, and dire concerns was simply the more acceptable alternative to saying, "An orbital storage facility... Gee, I hadn't thought of that."

On sci.space.policy, one person said that Mercury would be a good place to build solar power stations for beaming energy to all parts of the Solar System. I asked him why build the solar power plants in a place which was dark half the time, and suggested that even if we assume Mercury was the best source for the raw materials needed (there may be better asteroids, even this close to the sun), mass-drivers could be used lift them. After trying to suggest that maybe the surface of Mercury would make a good heat sink, he later said that no, he didn't have any kind of bias, but that I had "stupid blinkers on". To judge from appearances, I'd utterly failed to get him to see that a power station which operated continuously was worth twice as much as one only operating half the time.

We might say that up until now we've only been discussing amateurs, and that surely space professionals wouldn't let any kind of bias trip them up. But then we have Dr. David Criswell who has also proposed solar power stations in a place dark half the time (for 14 days at a time), in this case on the lunar surface. This was puzzling, because not only was Criswell aware of Gerard O'Neill's proposal for orbital manufacture of Solar Power Satellites (SPS) from lunar resources, he had even helped work on it. Why then was he now proposing solar power plants on the lunar surface? There could only be one reason for supposing the lunar surface proposal competitive with the orbital one: The expenses of lifting lunar resources into space were so overwhelming that avoiding it made even solar power stations less than half as effective more economical.

Criswell took note of some critical comments I'd made in my Space Settlement FAQ, and kindly sent me many papers he'd written on his Lunar Power Station (LPS) proposal. And I did make some modifications to  what I had written. I'd first like to say that if Dr. Criswell has calculated LPS could turn a profit, I've every reason to expect he's right. But I turned through the papers looking for the comparison with the O'Neill proposal which might have steered him in this new direction. All the papers had comparisons with ground-based solar and with Earth-launched SPS. None had detailed numerical comparisons with lunar-derived orbital SPS. The earliest one or two papers mentioned this option briefly only to dismiss it as impractical with little or no detailed discussion. Past that point, the High Frontier scenario was never again mentioned. (But I may now need to retract at least this point.)

It's true the O'Neill plan very much turns on the practicality and economics of mass-driver launch from the lunar surface. But if Criswell had discovered any fatal flaw in the mass-driver concept, he kept it to himself.

There are professional proposals for radio telescopes on the lunar farside. An aluminum noise shield less than a millimeter thick can do the same job as is proposed for the entire moon, leaving an orbital dish freely pointable in any direction, as well as easier to access from Earth. I've heard it argued that the stability of the lunar surface is indispensable where interferometric observations are concerned. But note that NASA is moving forward on an orbital mission which will indeed do optical interferometry in space. It could be that if one's primary concern is for staying within a fixed budget, as opposed to justifying lunar development desired for its own sake, more economical alternatives present themselves.

Planetary chauvinism may also influence most thinking regarding permanent human settlements beyond the Earth. It seems to be a near-universally-held opinion that setting up such communities on Mars will obviously be less expensive than in HEO. It's not considered close enough to even be worthy of question. Why? Because Martian communities will import only a bare minimum from elsewhere, whereas a habitat in free orbit will obviously import _everything_. This fact is considered to trump any additional expenses involved with operating at a much greater distance from the Earth.

The problem is that there simply aren't any studies of 10,000-person permanent habitats for Mars, at least not in anywhere near the level of numerical detail of the NASA space settlement studies. So in truth, direct comparisons are impossible to make. We would need an "Island One for Mars" study before both locations could be compared on the basis of similar aims and returns. The existing attitudes on the relative difficulties or expenses involved are based on what seems obvious to everyone, rather than on peer-reviewed studies.

Unable to assail the logic behind any of the half-dozen or so  points O'Neill made regarding the advantages of an orbital location over a planetary surface, most Mars advocates simply argue that these points are moot since orbital habitats are impractically difficult to set up in the first place. Is there anything to the widely-accepted truism that Mars is "easier" than orbital space? To answer this question, we must ask what Mars provides naturally which must be provided artificially in orbit.

One thing is gravity (though it must be pointed out that Mars provides the wrong level of gravity for maintaining what we presently consider normal muscle tone). Orbital habitats can provide any desired level of "gravity" by rotation. Is there any reason to expect this to be any significant initial or ongoing expense?

O'Neill calculated that the electric motor needed to spin up even his enormous Island Three habitat need only be about the size of a car engine. The vast cylinders could be spun up on a timescale of months using only the electricity generated by the sunlight falling on the end caps. One only has to overcome inertia. Ongoing power requirements are apt to be far smaller, given reasonably-well-designed bearings. Certainly there are reasons to expect most any space habitat to have a non-rotating section, but in a pinch this section could be dispensed with, and the entire habitat could rotate without friction as a monolithic unit. Incoming spacecraft could dock in the same manner we saw in the movie "2001".

The only other thing Mars gives us for free is a natural day/night cycle. In a space habitat, this would be accomplished by shifting large mirrors made of aluminized Mylar. Given the flimsiness and simplicity of the mirrors, there's no reason to expect any major expense here, either.

The more significant expenses involved with setting up human communities beyond the Earth will be: creating new industrial infrastructure totally from scratch, engineering large, pressurized volumes, and setting up and maintaining closed, balanced ecologies. Obviously these requirements will be much the same whether discussing Mars or orbital space.

It's difficult to avoid thinking that surely there's some savings in not having to build the very ground beneath one's feet. It surprises many to find that in an O'Neill habitat, the loading on the structure from the centrifugal force acting on the interior soil and furnishing is significantly less than the loading from the internal air pressure. Once you've engineered the required pressure vessel hull (which we must do in either case), you don't have that much further to go to engineer something safe to landscape and build houses on.

But discussions of which is easier may not be as relevant as which is most likely to come about in the first place. O'Neill felt that his orbital habitats would forever remain dreams unless he could propose some economic opportunity which they alone could exploit; one which would pay for the initial investment with profit and would balance the trade with Earth going forward. This would have to involve some service marketable to Earth (the only customer currently in existence), which nonetheless could be better performed in orbit than on the Earth's surface. He proposed the construction of SPS, built from space materials in HEO and then delivered to GEO, as this service.

It should be mentioned that past a point, O'Neill freely conceded that construction of SPS from space resources would precede large, Earthlike space habitats, and not the other way around. And in a similar vein, the use of the phrase "High Frontier" throughout this article should be interpreted as "significant manufacturing capability in HEO fed by space resources" rather than as "Island Three". Still, it remains that once we've set up the infrastructure needed to manufacture SPS from space materials, pretty much everything we need is in place to later build pleasant orbital habitats. Surely by the time SPS construction has ramped up to the point that orbital workers number in the thousands, something on the scale of Island One will have been built, if only to reduce worker turnover.

Mars advocates have said orbital habitats will never happen because SPS is a flawed business plan, but then propose habitats on Mars seemingly in the absence of any business plan at all. They also tend to minimize the importance of exports for the balancing of trade, perhaps only because Mars would seem to have little to sell Earth. Or alternately, may posit intellectual property as the export for the red planet. But it seems that if Mars settlements can balance their trade with sale of intellectual property to Earth, then space settlements should as well, even if SPS is a bust.

Bearing in mind that in the long run some humans may need no reason for living on Mars other than a love of the planet, High Frontier advocates see much that their scenario can offer to the enterprise of settling Mars. But Mars advocates tend to be dismissive of suggestions there are any contributions which the space islands could possibly make to their goals. This puzzled me, until I realized that there were two places the mind of the Mars enthusiast enjoys going to.

The first is to a near-term future, one in which the US government has gotten back into an Apollo frame of mind, and is willing to send scientific expeditions of four persons apiece to the planet Mars. Orbital habitats are certainly not needed for missions of this scope. Indeed, Robert Zubrin has successfully demonstrated that not even so much as the presently-existing LEO space station is needed for sensible execution of this plan.

The other place is the much more distant future of an independent Martian civilization. High Frontier has nothing to offer here either, since the Martian civilization is defined as independent.

Obviously much must happen between the one vision and the other. But the mind of the Mars advocate tends to skip lightly over this place. Narratives typically leap from small bases built up from the latter Mars Direct missions to Bradbury City with scarcely a paragraph or two on the vast intervening eras.

But these are the eras in which major manufacturing capability in HEO supplied with space materials has the most to offer Mars colonization efforts. Consider the first 10,000 tons of mining equipment, the first 10,000 tons of ore refineries, the first 10,000 tons of manufacturing facilities of every kind, and the spacecraft for transporting the first 10,000 colonists (along with all the above). Consider that before this can be sent to the red planet, it all must first be built by people who were born on this planet. But even if built by Earth people, these seeds of the new Martian civilization need not necessarily be assembled on the surface of the Earth. If all this can be produced in HEO from materials already in space, then this is a tremendous leg up on any attempts to colonize Mars. But since this era is not a place the mind of the Mars advocate tends to go to, they tend not to see or acknowledge this.

Gerard O'Neill's unexpected results prompted him to make the following remarks in "The High Frontier":

We should ask, critically and with appeal to the numbers, whether the best site for a growing advancing industrial society is Earth, the Moon, Mars, some other planet, or somewhere else entirely. Surprisingly, the answer will be inescapable - the best site is "somewhere else entirely."

But O'Neill's surprising answer seems largely forgotten in the 21st Century space advocacy community. Is there a reason other than that it _is_ surprising; than that it's ill-fitting to imaginations conditioned more by science fiction than by any real-life attempts to live permanently beyond the Earth?

Sometimes when space thinkers propose the building of a manufacturing plant, a solar power station, a radio telescope, or a permanent human settlement, I suspect they frequently proceed from an Earth-bound assumption. As we all know, the first step in building anything is finding a plot of ground upon which to build it. In my debates with many, I've seen little to convince me that they began with no preconceptions, gave due consideration to orbital locations as well as planetary ones, and only ruled out orbit after seeing major advantages to a planetary site. When called on this, the reasoning offered up is after-the-fact, as they struggle to justify a previously unexamined starting assumption they now feel committed to.

The problem with unspoken assumptions is that they remain unquestioned assumptions. We must train ourselves to think outside the planetary box when considering the best locations for all of our future activities beyond our current terrestrial home.

### * * *

## Lunar Solar Power Stations vs. the O'Neill Proposal

In May of 2006, Dr. David Criswell became aware of this article and contacted me to resume our debate about the relative merits of Lunar Solar Power (LSP) stations vs. lunar-resources-derived GEO SPS.

Dr. Criswell said that all of his comparisons were toward the GD-Convair study, which included SPS where 90% of the construction materials were lunar-derived (SSI later calculated this number could be boosted to 99% for SPS designs optimized for use of lunar materials). I'm sure my previous comment in this article would have been based on me going through the Criswell papers looking specifically for references to O'Neill or to manufacturing in HEO. Dr. Criswell went on to say he had calculated LSP could provide power at a cost 1/50 that of power delivered from SPS built as O'Neill had recommended.

Interestingly, Criswell said the GD-Convair study judged the lunar-material-derived SPS option less risky than the Earth-launched one for several issues, among them the environmental damage which would doubtless be done to the upper atmosphere of Earth by all of those thousands of mega-rockets thundering upward.

One very good point Dr. Criswell raised was that GEO SPS might suffer from an orbital debris problem absent from the lunar surface. My take on this is that hopefully a significant manned operational capability in GEO might mean a better ability to manage and combat the debris problem. But Criswell relates the severity of this hazard with the surface area of the satellites in GEO. To say that SPS would lead to a significant increase in this area is putting it mildly, to say the least.

He says that my emphasis on the day/night cycle of the moon and my assumption of a 2-to-1 advantage for GEO is wrong, making the point that GEO SPS, being a baseload (flat) source of power, must be similarly oversized around 2x in order to meet peak power demands. But I'm not convinced this is the best argument, since an oversized GEO SPS can obviously be selling excess power to secondary markets during off-peak hours.

Despite the fact Dr. Criswell brought up much new and helpful information and helped me appreciate certain aspects of LSP a bit better, I still can't entirely rid myself of the conviction a planetary bias may be involved here. When he says, "The Moon exists. You do not have to build it, and you can use its materials," I think we're veering from the point. The O'Neill proposal agrees the moon is the right source for the materials, and I don't think our choice is between building an orbital ore refinery or not, it's between building a refinery in orbit or on the lunar surface. Ditto manufacturing facilities.

It can't be denied lunar materials take a much longer path in the O'Neill scenario vs. LSP, and Criswell rightly points out that the more steps, the greater the expense. But lunar lift costs are a one-time expense. The 50% duty cycle resulting from the moon's day/night cycle is an operational disadvantage which lasts the lifetime of the power plant.

On the other hand, there are some at SSI who tell me there are too many unknowns to conclude that Criswell isn't right, and that power beaming from the moon should not present major problems.

I'll say that if Dr. David Criswell has come up with an alternative to SPS which can undersell it by a factor of 50, then he's done more to advance us toward space settlement in recent decades than anyone. There could be no doubt his LSP scenario would lead to the High Frontier. For example, any universe in which many thousands of square kilometers of the moon's surface is being coated in photovoltaic arrays, the manufacture of a lunar mass driver (the most massive part of which would be its PV array) would certainly be done on the lunar surface from local materials instead of it being sent up as a kit from Earth. Thus, in a future Criswell presents us, an important component of the O'Neill vision becomes trivially easy to manufacture.

Mike Combs  
May, 2006

##### mikecombs@aol.com
This is perhaps the only article I've written which was solicited. Someone was planning to publish a set of articles, and asked me to write one which used the Tunguska impact as a departure point. The publication plans fell through, so I just put it up on my website.

The concept of deflecting an asteroid on a collision course with Earth gets lots of attention. But even absent such a collision, there may be good economic reasons to learn how to move asteroids around.

#

# Averting Armageddon, with ROI

### by Mike Combs

###### mikecombs@aol.com

###### Copyright © 2008

2008 saw the centennial of the Tunguska event, which prompted us once again to consider: When will the next major asteroid strike occur? And is there anything we could do about it?

Tunguska of that era was a sparsely-inhabited region. For that reason, human fatalities and property damages were minimal. In the intervening century, the growth in human population has resulted in far fewer regions of the Earth similarly standing near-empty. The next such impact will surely result in greater loss of life and property. If such a strike takes place in an ocean (which chance would favor), the losses might paradoxically be even greater as global-scale tsunamis engulf shorelines.

Then we look nervously at the paleontological records of Extinction Level Events (ELEs) where some disaster overtakes the entire planet resulting in more species than not becoming extinct. And in at least some cases, an asteroid or comet is implicated.

So what can be done about it? If there is an asteroid out there with our name on it, then there are two considerations:

  1. Can we detect it a sufficient number of years in advance to take action? The situation here is poor, but improving. NASA surveys have gotten down to kilometer resolution, with plans to go lower. Canada will soon launch the Near Earth Object Surveillance Satellite (NEOSSat).

  2. Is there anything we can do to alter the orbit of a threatening object and thus avert a disaster of ghastly scale?

Shouldn't we be working to develop the techniques and technologies needed to move small solar system bodies around? This is a position being vigorously advocated by a number of groups, chief among them Rusty Schweickart's B612 Foundation.

For quite some years, the received wisdom on this issue was that we would use nuclear explosives to change the course of a small body on a path intersecting the Earth. Nuclear devices are certainly the biggest stick in humanity's technological arsenal.

But according to a 1998 **Nature** paper, while stand-off nuclear detonations might have some utility, nuclear devices might not be as useful as one might think. Many asteroids seem to be multi-lobed. A nuclear detonation might see a significant fraction of its energy going into the shifting of one lobe relative to the other, with correspondingly less energy going into a course deflection of the overall body.

Even if we had the good luck to be threatened by a non-lobed body, many asteroids may be less like a single rock and more like a loose conglomeration of bodies embedded in dust. Subjected to a nuclear explosion, such a "flying gravel pile" might separate. So we would find we had only succeeded in converting one single disaster into many separate ones. Sometimes Hollywood dramas speak of pulverizing an asteroid such that all of its pieces would "burn harmlessly in the atmosphere". But an entire sky alit with the blazes of entering debris would touch off surface fires of incomprehensible scale.

So are there any better methods for changing the course of an asteroid; something which can apply low but steady thrust for weeks or months rather than a sudden shock?

In the 1970's Princeton physicist Gerard O'Neill was working out a method for establishing settlements beyond the Earth which were not dependent on the conditions we find on the surfaces of other planets or moons. In both scientific papers and "The High Frontier" he advocated the construction of enormous, orbiting structures which rotated for artificial gravity and would contain within them Earthlike environments in closed ecologies. The unceasing power of the sun would be used to drive those ecologies and for power generation (indeed, such settlements might help pay for themselves by constructing solar power stations in orbit). This approach would seem to have many advantages over trying to make a go of it on other planets.

But one can immediately discard the notion of manufacturing the parts for these space settlements here on Earth and then launching them into orbit on a rocket. With habitat masses ranging from 4 to 10 million tons, this was clearly unfeasible for any plausible rocket system, regardless how improved over those currently in use.

This meant such space settlements (and solar power stations, if desired on a scale large enough to make a global difference) had to be constructed from materials already in space. O'Neill first turned to the moon, designing and even building working models of a device called a mass driver to function as a catapult capable of launching lunar ores to the L-2 point. This was a position in space from which the material could be collected for delivery to an orbital ore refinery.

The mass driver was a long, solar-powered structure with a series of electromagnetic coils running down its length. Recirculating buckets equipped with magnetic coils of their own could be rapidly accelerated down the length of the mass driver and then sharply decelerated, ejecting their contents out the end of the structure.

It was quickly realized that such a device built in space rather than on the lunar surface could function as a reaction engine. And moreover, a reaction engine which could use literally _anything_ as reaction mass. This neatly solved the problem of getting the kit for the lunar mass driver along with the needed mining and other support equipment from Earth orbit to lunar orbit. A shuttling mass driver reaction tug could haul the loads from one orbit to the other.

Shortly after, Brian O'Leary wrote papers advocating the use of mass driver reaction tugs to retrieve asteroidal resources to high orbits around the Earth using a portion of the material for reaction mass. It turns out asteroidal resources might have advantages over lunar ones. For one thing, a wider variety of materials are available, including volatiles rare or nonexistent on the moon. For another, a number of the Near Earth Asteroids then known (and even more are known now) have round trip delta-V's which compare favorably with that for the moon.

O'Leary had investigated possible trajectories back from certain NEAs which capitalized on gravity assists from Venus and the moon, and concluded that the requirements fell inside the technical capabilities of the mass driver reaction tug.

This is good news. If the goal is bringing many tons of asteroidal material back into near-Earth space, it's tempting to propose aerobraking through the Earth's atmosphere to slow down. But such maneuvers might never be permitted by Earth dwellers fearing the consequences of a load of ore going off course. But calculations seemed to indicate that capture of ET materials into cislunar space need not depend on anything as dramatic as a screaming dive through our atmosphere.

If mass driver reaction tugs can economically deliver asteroidal material to high Earth orbits, then there's no reason to suppose that orbital habitats need be any more difficult to build than similar settlements on the moon or Mars. The needed raw material would be close at hand.

But for this concept are we limited to studies conducted back in the era when disco was king and bell-bottom pants the fashion? Perhaps not. In 2004, SpaceWorks Engineering, Inc. did a study involving a large number of robotic space craft which could be dispatched to an asteroid, latch on, and use telescoping mass drivers to fire off bits of the asteroid sequentially, thus altering its trajectory.

Undaunted by words with negative connotations, they cheerfully gave their system the acronym MADMEN: Modular Asteroid Deflection Mission Ejector Node. But far from madness, developing the technology to change the courses of small bodies in our solar system might be the sanest thing we could do.

Any system which can use the raw material of the asteroid as reaction mass has a considerable advantage over any system which has to haul the needed fuel to the asteroid. Additionally, if we're interested in retrieval of useful resources, a system which can use any raw material as reaction mass is even more advantageous. The problem with some proposals such as solar or nuclear steam rockets is that you're throwing away the most valuable part of the asteroid. It matters little to the mass driver what material is coming out the exhaust. If we're engaging in ore refining on the trip back to cislunar space, we might well use liquid oxygen as reaction mass, which means we're throwing away the least valuable part. (Any space mining operation can expect to have a surplus of oxygen available.)

High Frontier enthusiast Steve Whitting has drawn a comparison between mass driver reaction tugs and the steam-powered paddleboats which cruised the Mississippi back in frontier days. When their fuel of coal neared depletion, the crew could always pull up to a bank, gather deadwood, and use that to continue firing their boilers. Like steamboats, mass driver spacecraft offer the advantage of being able to "refuel" (technically, gather reaction mass) from available material, including the regolith of an asteroid.

One of the newest proposals for changing the course of asteroids involves a "gravity tractor" which gets us around the technical challenges of halting the rotation of an asteroid before we can begin operations. But there seems no reason to doubt that a mass driver reaction tug could be used in such a configuration. One of the conceptual designs for an ore retriever featured three parallel mass driver engines in a triangular array with struts connecting them to each other and to an enormous sack of asteroidal soil in the middle. If the three mass drivers were angled slightly apart such that their exhaust missed an asteroid being pulled by the vehicle's gravity, then we have a mass driver powered gravity tractor.

We've talked about using asteroidal resources to create solar power stations and human settlements in high orbit. Might there be any materials in asteroids worth bringing back to the surface of Earth? Some have tried to make a case for platinum group metals. Detractors have pointed out that dumping megatons of precious metals on the market will serve to make them less precious. But consider this. A world in which we are manufacturing several Solar Power Satellites a year might be a world where electric cars come into their own. Their fuel cells will require platinum as a catalyst. An asteroidal platinum retrieval operation might largely piggy-back off of an existing asteroidal-ore-for-SPS operation. The expansion of the electric car industry enabled by a new, renewable source of abundant electricity might make the platinum market considerably more elastic than otherwise (demand might expand nearly as dramatically as the supply).

Any technology developed to haul asteroids (or even portions thereof) around the solar system for profitable use can certainly be applied to preventing the next big asteroid strike. The problem with convincing Joe Six-pack that many tens of billions of dollars of taxpayer's money should be spent developing the techniques to shift the courses of asteroids is that, if honest, we must tell him that the next big impact could happen next Tuesday, or a thousand years from now. It's hard to argue for this generation spending the money as opposed to a future one.

What we're essentially trying to sell is a planetary insurance policy. But what if it could be a purchase instead?

Entrepreneurs who have an interest in building large solar power stations or settlements in high Earth orbit might well spend their own money to develop the technologies needed to change the orbits of asteroids. And if we do spot that rock which has the Earth in its cross-hairs, wouldn't it be better to go out and face it with technologies and techniques which have already been in routine economic use for years than to try and develop them in a crash-course program? When the stakes are this high, that's not the time to realize you haven't quite shook all of the bugs out of the system yet.

A large program of using asteroidal resources for economic gain would make our planet safer in the long term. Such a program would seek out low delta-V targets, which means NEAs crossing the Earth's orbit would get used up first. But even a long time before then, a sizable asteroid striking the Earth would simply never happen in such a High Frontier universe. This would be a universe of space telescopes the size of large buildings, and changing the course of an asteroid or comet would be all in a day's work. There would be people living out there between us and an approaching boulder. They would be in a far better position to do something about it than we here at the bottom of our gravitational hole.

Some have said we should establish independent space settlements in case the Earth suffers an ELE impact. I say we should advance to the kind of society capable of building those settlements as such a society would never allow a significant Earth impact in the first place.

Those who are concerned about the dangers from asteroids should certainly advocate near-term strategies and technologies. But I think they should also stand as advocates of a High Frontier future, as this future would see Earth at its safest from such hideous threats.

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Other writings from Mike Combs

