Lifeboat Foundation

Predatory plants will probably not trot over to attack us as we amble to our cars any time soon, John Wyndham’s classic sci-fi novel Day of the Triffids notwithstanding. And yet, truth may well turn out to be stranger than fiction, if we only wait. In the case of plants coming out of genetic engineering labs that wait might perhaps be 10 years – or less. In the case of mother nature, radically new tricks might require waits of 10 million or 100 million years – or more.

Spore Storm. Anthrax bacteria can kill quickly, overwhelming an animal’s natural defenses by multiplying and secreting toxins. The toxins build up in the body and they, not the organisms themselves, are what ultimately cause death. Once dead, the animal host is no longer a suitable source of food, shelter, and oxygen for the anthrax. Now something interesting happens. Some of the anthrax bacteria succeed in growing, inside their bodies, a tough cover encapsulating their genes and certain other cell components. This is called an endospore, and is capable of withstanding environmental conditions for long periods of time – several decades has been documented. When conditions finally become favorable (e.g. it is eaten by a host animal), it comes back to life, attempts to grow and divide, infects the new host, and the cycle begins anew.

Many terms derived from “spore” exist, from aeciospores to zygospores, and endospores are just one kind. Some plants reproduce via spores, ferns for example. Spores do nothing until conditions for growth are promising. Then they spring into action. Plant spores sprout into baby plants called sporelings (spores become sporelings, like seeds become seedlings). The sporelings eventually become full grown plants if all goes well. However, many familiar plants produce seeds, not spores. Seeds are much bigger and carry much more nutrition, used to give a baby plant a good start, or perhaps sustain an animal that eats it. Spores, on the other hand, are microscopic.

Oaks produce acorns, which are large seeds, not microscopic spores. But even the mightiest oak, like a tiny blade of grass, is missing a big opportunity. That is the opportunity for each cell in each leaf to create an endospore, instead of uselessly falling to the ground to rot when the leaf gets old or winter approaches. In the future, by natural accident or human design, some plant may become the first to grab that opportunity, and things may never be the same again. Instead of dropping their leaves, these plants will release a dust storm as each leaf transforms into millions upon millions of endospores, blowing in the wind. These endospores will eventually land and try to start a new plant, in the spring in temperate climates or any time in warmer conditions. Such spore-producing plants could continue to also produce seeds as they always have, but rather than waste their spent leaves along with an additional opportunity to propagate, they will instead much more efficient convert those leaves into quantities of endospores. This will give them an advantage over traditional plants, out-competing them and eventually dominating the earth, just as flowering plants have come to dominate since they first evolved at least 140 million years ago. Let us hope these superplants make useful crops. That way their domination will be useful to us.

Next Time: A Return to Roots

It is a refreshing fact that the prospects for human survival are substantially higher if we live on two worlds, instead of just Earth. The moon, say, or Mars… every extraterrestrial body poses unique technical challenges to colonization. Yet nearly all are at least potentially habitable – in theory. Our survival prospects climb higher for three worlds, higher still for four. The more worlds we colonize, the more likely a colony on at least one of them will still exist at any given future moment. It’s like flipping quarters: the more you flip, the greater the chance at least one will come up heads.

Last time: More Exotic Colonization Options. This time: Pluto and Eris – the Outer Limits

The outer limits: Pluto and Eris. Pluto just does not get enough respect. Last hired and first fired of the planets, it was discovered on Tuesday, February 18, 1930, in Flagstaff, Arizona by self-made astronomer Clyde Tombaugh. It was forced into retirement by an act of the International Astronomical Union, which revoked its full planetary status on August 24, 2006, after only 76 years on the job. Pluto has been technically renamed “134340 Pluto” and relegated to dwarf planet status, to the continued consternation of Plutophiles everywhere.  To make things worse, it is not even the biggest dwarf planet, or for that matter the most distant. Those honors go to Eris, discovered in 2005 and not that well-respected either (many people have never even heard of it). As targets for colonization these bodies have problems, though nothing like those associated with the gas giant planets or even Venus. The main problems are getting there in reasonable time, and obtaining enough light energy to warm the colony (which is sealed to keep the air in), to grow food, and to generate electricity such as with solar cells.

A one-way trip to Pluto is feasible in about 9 years. The New Horizons spacecraft launch of January 19, 2006, destination Pluto, was designed with a planned travel time of 9 years and 176 days. Eris is less than four times as far away as Pluto. Sometimes it can actually be closer to the sun than Pluto, though this won’t happen next for about 800 years.

Prospective colonists will have severe energy challenges once they manage to actually get there. Pluto’s distance from the sun ranges from 29.7 times Earth’s average distance, up to 49.3 times Earth, depending on where it is in it’s rather uncircular orbit. For Eris, the range is from 37.8 to 97.6 times Earth. Unfortunately the brightness of the sun is related to the square of the distance, not the distance itself, so the sun on Pluto is actually between 880 and 2,431 times weaker than on Earth (i.e., 29.7×29.7 to 49.3×49.3).

With the sun so weak, sunburn would be the least of your worries. In essence, you’d need 2,431 computer-controlled mirrors all reflecting the sun to the same spot, to be sure to get up to at least Earth’s sunlight intensity at that spot. Then, if that spot was inside an transparent, airtight bubble, you could grow crops there, right at that spot. If you wanted to grow 1 acre of crops, on the order of what’s needed to support a person, you’d need up to 2,431 acres of computer-controlled mirrors. During favorable periods you’d need less, as “few” as 880 acres, but you do have to eat during the unfavorable times too. For Eris, the sunlight is as low as 9,518 times weaker than Earth (implying 9,518 mirrors for Earth-style light intensity). Though this sounds dim, it is actually about 35 times brighter than the full moon, so you could see well enough to get around without artificial light or mirrors. Still, mirror manufacturing definitely needs to get more cost-effective before colonization becomes feasible, unless some other energy source can be found besides the distant sun. Once the energy problem is solved – well, bon voyage!

What we can do now

Tracking the advance of space technology. It would be good to understand how quickly space-faring technology is advancing. Research on elaborating, testing, standardizing and using such technology tracking methodologies should be supported by academic research, incentivized by government research funding. That way we would know better what to get ready for in terms of a time frame for future space colonization. The leading approach could be expanded upon. It is termed “Technology Readiness Levels,” or TRLs, and is used in the US by the National Astronautics and Space Administration (NASA) and the Department of Defense (DoD) as well as other organizations worldwide. TRLs classify relevant technologies on a spectrum, such as from speculative on to mature. “Speculative” describes, for example, proposals for faster-than-light travel via cosmic wormholes. “Mature,” on the other hand, could be applied to space systems that reach operational status, like the US space shuttles of the early 21st century.

From sunbathing to moonbathing to starbathing. Closer to home, it is useful to keep in mind that moonlight is hundreds of thousands of times dimmer than sunlight. This means that, though sunbathing is hazardous even with sunscreen (as we will see later), moonbathing is perfectly harmless, and perhaps even fun. Feel free to go right ahead. But don’t expect to get a moontan as the light is simply too muted and pale, even compared to sunshine on Pluto or Eris. So that’s the situation with moonlight…but what about starlight?

The brightest star in the heavens is Sirius, with an apparent magnitude of -1.47. This is quite a bit dimmer even than the full moon, whose apparent magnitude is about -12.9. The lower the apparent magnitude, the brighter the object. The sun, for example, has an apparent magnitude of -26.7. We can explore this issue further, in case you run into someone inclined to concentrate starlight from Sirius to sunlight-equivalent intensity for the exotic purpose of tanning by starbathing. A difference in apparent magnitude of 5 is defined as a 100-fold change in brightness. The difference in apparent magnitude between the sun and Sirius is a little over 25. At a factor of 100 change in brightness for every 5 levels of magnitude, 25 levels means a hundred-fold brightness change compounded 5 times, for a total change in brightness of 100×100x100×100x100, or 10 billion. In other words, starlight from Sirius would need to be concentrated more than 10 billion times to reach the intensity of sunlight. At roughly 4 billion square inches in a square mile, that means about 3 square miles of starlight from Sirius focused onto a single square inch. Since starbathing requires more than a square inch of light, that pretty much means an entire metropolitan area or its equivalent devoted to focusing Sirian starlight onto your beach towel. Other stars are dimmer and would require even more area.

From starbathing back to sunbathing. However impractical, starbathing at sunlight-equivalent intensity is possible in principle! However, it would be unhealthy, and for the same reason that sunbathing is unhealthy. Sirius is much hotter than the sun so its light is more skewed toward the ultraviolet. Thus protecting the skin from UV (ultraviolet) exposure from super-concentrated starlight would be very important. Sunscreens are typically rated in terms of ability to filter out B (medium wave) type UV (abbreviated UVB), which causes sunburn. They tend to let through A (long wave) type UV. This UVA does not cause sunburn, but does damage the skin, causing the most dangerous kind of skin cancer, malignant melanoma. This is consistent with the lack of evidence that ordinary sunscreen use protects against this often-deadly cancer. Even ordinary window glass does not screen out UVA reliably. In short, star-tanning, like suntanning, should be avoided. On the other hand, appropriate sun exposure is needed to create vitamin D in the skin. And ordinary starlight is so attenuated that starbathing at night under unconcentrated starlight is perfectly fine if you feel like doing it, just like moonbathing. Enjoy!

Communing with your inner colonist. Take up vegetable gardening, just like space colonists likely will! Food production in extraterrestrial colonies might involve hydroponic tanks or chemical factories producing soylents of various colors for food. But production may also involve growing plants, just like on Earth. Off-Earth farming will resemble vegetable gardening more than commercial agriculture. Instead of acre after acre of a single crop, colonists will grow many different kinds of plants in modest quantities inside the colony’s bubble. That will give the colonies more diverse and thus robust ecosystems. It will also make for a more varied diet for the colonists, which is healthier as well as better-tasting. So, while growing your own vegetable garden, you can work knowing that you are doing what the space colonists of the future will likely do. Your gardening experiences here on Earth, both good and bad, will mirror to a significant degree those of future space colonists and deepen your understanding of space colony life.

It is a refreshing fact that the prospects for human survival are substantially higher if we live on two worlds, instead of just Earth. The moon, say, or Mars… every extraterrestrial body poses unique technical challenges to colonization. Yet nearly all are at least potentially habitable – in theory. Our survival prospects climb higher for three worlds, higher still for four. The more worlds we colonize, the more likely a colony on at least one of them will still exist at any given future moment. It’s like flipping quarters: the more you flip, the greater the chance at least one will come up heads.

Last time: Half a Planet is Better Than None: Ceres. This time: Even More Exotic Colonization Options

More exotic colonization options. If Ceres is not exotic enough, let’s consider a few even more distant options. Colonizing the gas giants, Jupiter, Saturn, Uranus and Neptune would make colonizing a giant balloon 30 miles above the surface of Venus seem like a piece of cake. These planets are cold, get little sunlight useful for growing food and providing power, have poisonous atmospheres, and don’t have a definite surface to build (or even float) on, because the atmosphere just gets denser and denser (but at least warmer and warmer) as you go down. “Never say never” perhaps, but those places have got to be near the end of most people’s colonization lists. On the other hand, gas giants are not without temptation: some scientists speculate that far enough down, large diamond bergs drift in liquid carbon, which might tempt some to try to fish them out. A typical iceberg on Earth might easily weigh a couple hundred thousand tons; a diamond berg that heavy would weigh 907 billion carats and change (over 180 million carats of “change,” if you want to be nit-picky about it). That’s a big diamond, and expensive too. It would make a mighty fine cocktail ring, don’t you think? Of course the cocktail party would have to be in a reeeeal big hall!

Setting aside the more daring, diamond-struck adventurers, a more likely bet for colonization would be certain moons of these planets. Our solar system has no Pandora, as popularized by the movie Avatar but first described in the Strugatsky brothers’ 1960’s Russian sci-fi series Noon Universe. But Saturn’s moon Titan has rivers, lakes and rain. True, they are mostly of liquid methane, but hey, at least the ground is mostly water ice. Jupiter’s Europa has lots of ice too, with liquid water underneath, but also lots of radiation at the surface. Indeed, considerable water ice is available on many of the moons of the gas giant planets. Jupiter, Saturn, Uranus, and Neptune collectively have no less than 14 moons with diameters of over 500 miles – and a lot of smaller moons as well. Of course some of these moons are more forbidding than others.

Talk about forbidding, it’s a cold day in hell on Io, a moon of Jupiter. Io is considered the most volcanically active body in the solar system. Rather than mere ordinary liquid rock, however, what issues forth from Io’s volcanoes has a high sulfur content. Sulfur is the modern name for what used to be called “brimstone,” so Io is hellish indeed. There are even thought to be fuming lakes of the stuff on Io. Yet most of the sulfur (er, brimstone) covered surface is frigidly cold.

At least the intense radiation bathing the surface interacts with Jupiter’s magnetic field to produce huge amounts of high-tension electricity…just waiting to be tapped by its future diabolical, energy-hungry, and doubtless space heater-carrying inhabitants. But who would want to inhabit such a place? Maybe no one. In fact, Io might be the perfect place for punishment – a genuine living hell! A hellish prison from which no one could escape, since prisoners would not be issued space ships. Io puts ordinary supermax prisons to shame. This one is more of a superdupermax. Meanwhile Jupiter hangs in the sky, an enormous, glowing, many-featured orb. It should make quite a beautiful sight (viewed through the required heavy-duty radiation shielding, of course!).

Next time: Pluto and Eris

It is a refreshing fact that the prospects for human survival are substantially higher if we live on two worlds, instead of just Earth. The moon, say, or Mars… every extraterrestrial body poses unique technical challenges to colonization. Yet nearly all are at least potentially habitable – in theory. Our survival prospects climb higher for three worlds, higher still for four. The more worlds we colonize, the more likely a colony on at least one of them will still exist at any given future moment. It’s like flipping quarters: the more you flip, the greater the chance at least one will come up heads.

Last time: the Martians. This time: Half a Planet is Better Than None

Half a planet is better than none. You might not have heard of Ceres (pronounced like “series”), but it exists - in the asteroid belt between Mars and Jupiter. Though large by asteroid standards – it is the largest – it is officially classified as a ‘dwarf planet.’ With a diameter of 590 miles it is indeed dwarfed by Earth’s 7,920 miles, or thirteen times as much.  Surface area is more relevant to colonization than diameter, however, and just as a foot has 12 inches but a square foot has 12×12 or 144 square inches, the surface area of earth is 13×13 or 169 times greater than that of Ceres.  Yet, if you stood on its surface it certainly wouldn’t feel small. Geometry tells us that to a person standing on the surface, Earth’s horizon is only a little more than double Ceres’.  That’s enough to give a similar sensation of distance, even though this dwarf planet is so much tinier than Earth.

On the other hand, other facts of day-by-day life on Ceres are downright out of this world compared to our experiences on mothership Earth. The Cerean day is a minute or so longer than its rotational period of 9 hours, 4 minutes and 27 seconds. (Similarly, Earth’s 24-hour day is 3 minutes 56 seconds longer than its rotational period of 23 hours, 56 minutes and 4 seconds. The Earth is orbiting around the sun at the same time as it spins around like a top. After spinning around exactly once, the Earth has also moved to a slightly different spot in its orbit, so the sun’s light comes from a slightly different direction, lighting up a slightly different half of the Earth. This has the effect of delaying sunrise on average by that 3 minutes 56 seconds.) Since a Cerean day is just a few minutes over 9 Earth hours, for convenience the Cereans may define their hour so there are exactly 9 of them in a Cerean day. The tiny difference between an Earth hour and a Cerean hour (half a minute) would be imperceptible.

Life with days of 9 hours would be an interesting experience. A circadian sleep-wake cycle within that time frame is probably ridiculous, but a 3-day (Cereans call it a “triday”) cycle of 27 hours might work nicely. You would rarely have trouble getting up, since the 27 hours compared to Earth’s 24 means that getting up late by Earth’s standards would still be early on Ceres, so you could get a few extra things done before leaving for work. And with everyone living in a bubble, the commute would be shorter too. The following typical schedule will help you prepare for your move (courtesy Ceres Bureau of Tourism and Immigration).

Table. Typical Cerean resident’s schedule.

6:00 a.m.: Morning sunrise. Jump out of bed if not already up (gravity is low, and you are well rested).

9:00 a.m.: Arrive at work.

9:59 a.m.: The hour only goes up to 9, unlike 12 on Earth, so in another minute it will be 1:00.

1:00 m.d.: Ante-midday (a.m.) period transitions to midday (m.) period.

1:30 m.d.: Midday sunset.

3:00 m.d.: Firstlunch.

3:30 m.d.: Back to work.

6:00 m.d.: Midday sunrise.

6:30 m.d.: Secondlunch.

7:00 m.d.: Back to work.

9:59 m.d.: Work will be over in another minute.

1:00 p.m.: Work over. Transition to post-midday (p.m.) period. Go home.

1:30 p.m.: Evening sunset.

5:00 p.m.: Bed time. You’ve been up 17 hours, and the Ceres Bureau of Health notes that it is easier to fall asleep while it is still dark. Your Earth-evolved 24-hour clock is perpetually trying to catch up to the Ceres 27-hour triday cycle, making you sleepy by now, yet alert by the time to rise. You are ready to begin 10 hours in bed. (Bureau of Health Memo 3862B suggests 9 hours of sleep out of 27 is commonly adequate, and provides suggestions for the remaining hour for those seeking guidance on the matter.)

6:00 p.m.: Nighttime sunrise. You are asleep.

9:30 p.m.: Approximate time to begin meditative wakeful state (was called “watching” on Earth before artificial lighting became common).

9:59 p.m.: One more minute before it is 1:00 a.m.

1:00 a.m.: Transition into a.m. period. New calendar date starts.

1:30 a.m.: Nighttime sunset. End roughly hourlong “watching” period and go back to sleep.

6:00 a.m.: Sunrise. Jump out of bed again if not already up.

Very low gravity. With gravity only about 1/36 Earth’s, things are different indeed. Try this now: jump just hard enough to get an inch off the ground. On Ceres, that would get you about 3 feet up. Can you jump a foot? On Ceres you’d fly up 36 feet (or hit the ceiling). Walking around, one would tend to bounce off the ground with each step, which might resemble a flying leap more than a step. Running would be effortless and fast. It would probably feel a lot like flying. For the grueling around-the-world trek that groups of young Cereans (called “trekkies”) take before being welcomed into adult society, they are trained to swing a long trekking pole at the ground, the tip hitting obliquely at about 20 miles per hour. This propels the youths forward at that speed (see notes), and up enough so their feet never touch the ground. Indoors, one would need to walk in a more controlled fashion, without pushing downward against the floor more during some parts than other parts of the average step, because that would tend to send you flying upwards, potentially making it hard to stop before careening into the nearest wall or even hitting your head on the ceiling. To walk the Cerean way, push backwards against the floor without any extra downward push, using your gluteal (buttock) muscles to “pull” your heel backward with each step. The trick is to not push off with the front of your foot. Try it! It feels odd at first here on Earth but, with a just a little practice, you’ll be ready for your Cerean adventure.

Extraterrestrial terrorism. Terrorists and gunslingers on Ceres could create a form of chaos not possible on Earth. Bullets could be fired into orbit. Where the orbit brings them nearly to the surface, they could actually hit an innocent bystander years after they were fired. There is no atmosphere to slow them down! Earth firearms work on Ceres. Muzzle velocities vary depending on type of gun. Some firearms cannot launch a bullet into Cerean orbit, while others fire a bullet so fast that instead of orbiting it escapes the gravity well of Ceres entirely and flies off into space. For intermediate power guns, the true velocity can be made more or less than the muzzle velocity by firing in the direction Ceres rotates, or against it, or some other direction. By the same principle, rockets here on Earth are often fired near the equator because the ground is moving eastward (which is why the sun rises in the east) around the South Pole-North Pole axis fastest there, and that gives the rockets a speed boost. Thus, fired carelessly or maliciously, many guns could put a bullet into an orbit that comes arbitrarily close to the surface.

Recently, a youth on trek nearly lost her life from an orbiting bullet! People talked about it non-stop for weeks (since normally, nothing happens on Ceres). She jumped up only ten feet (equivalent to jumping up about 3 inches on Earth), and an orbiting bullet punctured her space suit, grazing an elbow. Fortunately other youths in the party responded quickly, heroically patching her space suit before too much air was lost, then using a special tourniquet to temporarily apply pressure to the injury through the suit. While the trek is the bridge to adulthood on Ceres, no one wants such heroism to become necessary. Guns aren’t much use on Ceres anyway, except staple guns.

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

The system NASA uses can be summed up as follows:

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

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

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

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

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

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

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

Are there any ideas we’re missing here?

It is a refreshing fact that the prospects for human survival are substantially higher if we live on two worlds, instead of just Earth. The moon, say, or Mars… every extraterrestrial body poses unique technical challenges to colonization, and nearly all are at least potentially habitable – in theory. Our survival prospects climb higher for three worlds, higher still for four. The more worlds we colonize, the more likely a colony on at least one of them will still exist at any given future moment. It’s like flipping quarters: the more you flip, the greater the chance at least one will come up heads – the probability calculations are the same.

Last time: the Moon – and Earth. This time: the Martians.

The Martians.

” ‘Now I’m going to show you the Martians,’ said Dad.” “They reached the canal. It was long and straight and cool and wet and reflective in the night. ‘I’ve always wanted to see a Martian,’ said Michael. ‘Where are they, Dad?’ ” ” ‘There they are,’ said Dad, and [he] pointed straight down. The Martians were there – in the canal – reflected in the water.” - The Million-Year Picnic, in The Martian Chronicles, Ray Bradbury, 1950.

I can get a bit choked up on that passage, and will call the first Martian colony “Chroniclia” (which is so much more evocative than, say, “Mars Colony 1″). It’s first leader: Chroniculus I. (Again, more evocative than Chroniculus’s birth name, Bart Smith). Chroniclia will no doubt be established near the Martian equator. The poles are too cold. Even if you wouldn’t mind seeing dry ice “snow” through the transparent dome wall, it would be hard to keep the dome comfortably warm, even with a double- or triple-walled dome designed to retain warmth, especially at night. Better to put the dome at the equator, where the surface temperature can get as high as 65 or 70° F. A location near frozen underground water will be helpful. At night the surface goes below -100°, so the dome will need to be able to trap and retain solar heat overnight, perhaps using water pools or the ground for heat storage. The dome also needs to be airtight and strong enough to hold pressure, because the Martian atmosphere is so thin. On a positive note, the atmosphere is mostly carbon dioxide, which can be pumped into the dome as needed to support crop growth (plants need it) and manufacture of carbon-based materials like plastics. The only noxious component in the atmosphere is carbon monoxide, at 700 parts per million. More than about 50 ppm presents health risks, so pumping in much Martian air would necessitate measures to remove the carbon monoxide. Under the heroic leader Chroniculus II, a legend known to succeeding generations as Mother Of Mars (MOM for short), Chroniclia may have perfected dome construction of tough, transparent, locally manufactured plastics much cheaper than glass. Population increase will motivate using technology such as that to build new domes – and fast – as a plausible steady rate of population growth (such as 2%/year) will crowd the Martian surface with a teeming civilization in a matter of under a 1,000 Earth years.

A few other characteristics of Mars will lend local color to life there. The Martian day is 24 hours, 39 minutes and 35 seconds long. This is perfect – much better than Earth for the many of us who would appreciate waking up 40 minutes later every morning. On the other hand a Martian year is roughly double an Earth year, so holidays will be a lot less frequent unless more of them are instituted. Maybe the birthdays of some national heroes could be celebrated (Chroniculus I day, MOM’s day, etc.). Also the gravity is only 38% of Earth’s, so if you weigh 170 lb. here on Earth, on Mars you would weigh just under 65 lb. and could jump like a hyperactive kangaroo. That would be fun. But the potential downside to low gravity is its long term effects on health, which are not known. It would complicate things considerably if gravity has to be augmented by curved, spinning floors to maintain health. Maybe a regular regimen of rigorous calisthenics would be enough. Would you prefer that?

It is a refreshing fact that the prospects for human survival are substantially higher if we live on two worlds, instead of just Earth. The moon, say, or Mars… every extraterrestrial body poses unique technical challenges to colonization, and nearly all are at least potentially habitable – in theory. Survival prospects climb higher for three worlds, higher still for four. The more worlds we colonize, the more likely a colony on at least one of them will still exist at any given future moment. It’s like flipping quarters: the more you flip, the more likely at least one will come up heads – the probability calculations are the same.

Last time: Venus. This time: the Moon – and Earth.

—

The Moon

“From the Earth to the Moon” is a book by the science fiction pioneer, novelist Jules Verne (1828 – 1905). The explorers in that classic tale found huge “mooncalves,” breathable air and extensive underground cities, but no green cheese. Modern colonizers will instead have to contend with a much more Mercury-like environment. Thus many considerations facing the colony of Mercuria also face future residents of the moon, though of course there are differences as well. Let us call the first moontown “Luna,” and see how the problems facing its citizens (who may call themselves “Lunarians”) necessarily differ from those of the Mercurians.

Daytime on the Moon lasts an average 13.66 earth day, several hours shy of 2 weeks, and the same for nighttime. Since a fortnight is two weeks, Lunarians can just dispense with the term “night” and use “fortnight” instead. This is a quite different experience from here on Earth, and different from Mercury as well, where nighttime drags on for 88 Earth days. One approach to finding a place to hang your hat on the moon is mooncaves (not mooncalves). Astronomers believe there are enough caves, created by ancient flowing lava and called lava tubes, to give colonists choices. Although living in caves might not sound super-advanced and high tech, keep in mind these caves are on the moon (and also, as the saying goes, “be it ever so humble, there’s no place like home”). For an artificially warmed, above-ground colony with access to ice for water, the same strategy for an ideal location applies as for Mercury: a transparent, UV-shielding dome above ground, in a pit of eternal shadow inside of a polar crater, lit by sunlight (to grow crops with and raise the temperature) reflected from mirrors installed at an adjacent peak of eternal light. The best currently known location for Lunaria is the Mount Yewridge area near the South Pole. A spot on Mount Yewridge is almost permanently lit, and the mountain is within the polar area, which is situated in a large depression containing plenty of areas of eternal shadow.

Finally, the Moon is a lot closer and easier to get to and build on than Mercury. Thus the Moon colony of Lunaria can expect to be founded much sooner than Mercuria, perhaps by your kids or even yourself.

Earth

Why not colonize Earth? The obvious objection is that we’ve already colonized Earth. Yet, consider the vast uninhabited areas ripe for colonization. Huge deserts. Frigid Antarctic wilderness. Vast ocean surfaces! Sealed domes in the deserts are the easiest. Floating sealed domes are next in difficulty, and Antarctica is the toughest challenge. If self-sufficiency breaks down, colonists could return to civilization with relative ease, compared to failure of an off-planet colony which could mean almost certain death. A further advantage of developing self-sufficient colonies on Earth is the opportunity to get a good start on some of the same technologies that would be needed in off-planet colonies.

(Next time: Mars)

It is a refreshing fact that the prospects for survival of the human race are substantially higher if we live on two worlds, instead of just the current one, Earth. The moon, say, or Venus – every extraterrestrial body poses unique technical challenges to colonization, and nearly all are at least potentially habitable (in theory). Survival prospects climb higher for three worlds, higher still for four… The more worlds we colonize, the more likely a colony on at least one of them will still exist at any given moment in future history. It’s like flipping quarters: the more you flip, the more likely at least one of them will come up heads – the probability calculations are the same.

Last time: Mercury. This time: Venus.

Colonizing Venus: Huh?

There is a surprising undercurrent of interest in colonizing Venus, even though a less likely place for it could hardly be imagined. As of this writing, Google notes over 15x more hits on the query “colonizing Venus” than on “colonizing Mercury” (bleak though it is, Mercury is far more hospitable!). Even the query “colonizing Earth” fails to register even twice as many hits as “colonizing Venus,” though the number (billions) of those actually colonizing Earth greatly exceeds the number (zero) colonizing Venus.

Although Venus is about 2x as far from the sun as Mercury, therefore receiving only about 1/(2 x 2)=1/4 the sunlight intensity (the so-called “inverse square” law), Venus is actually hotter than Mercury, because it suffers from a major greenhouse effect. Like Earth but much more severely, it is due in significant degree to the carbon dioxide in its atmosphere. But Venus has a lot more carbon dioxide than Earth. The greenhouse effect makes its surface a fairly steady 860° F. That’s hot. Sending global warming skeptic spokespersons and their fowl to visit Venus would really cook their goose!

Fans of Venusian colonization – from whose ranks would presumably come the necessary volunteers – could find Earth-like temperatures and pressures about 30 miles above the surface. . . hence, the city-in-a-giant-balloon concept. A 1-mile diameter balloon containing an Earth-like atmosphere would generate about 3 million tons of lift in the denser, carbon dioxide-rich Venusian atmosphere at an altitude of 30 miles up, where temperatures and pressures are pleasant for us humans. That’s enough lift to carry a reasonably sized self-sustaining colony if, in its construction, the balloon could be made light enough. Best of luck! Just don’t fall out, because a 30 mile drop into dense, superheated gases is nothing to sneeze at.

Reference

“A 1-mile diameter balloon…would generate about 3 million tons of lift in the… Venusian atmosphere.” Derived from G. A. Landis, Colonization of Venus, Proceedings of the Space Technology and Applications International Forum (STAIF), Albuquerque, Feb. 2-6, 2003. ISBN 0-7354-0114-4. Http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20030022668_2003025525.pdf.

It is a refreshing fact that the prospects for survival of the human race are substantially higher if we live on two worlds, instead of just the current one, Earth. The moon, say, or Mercury – every extraterrestrial body poses unique technical challenges to colonization, and nearly all are at least potentially habitable (in theory). Survival prospects climb higher for three worlds, higher still for four… The more worlds we colonize, the more likely a colony on at least one of them will still exist at any given moment in future history. It’s like flipping quarters: the more quarters you flip, the more likely at least one of them will land heads – the probability calculations are the same.

Let’s start near the sun and work our way out.

Colonizing Mercury: the major roadblocks and their solutions. Mercury is the planet closest to the sun, and we begin by giving our putative future settlement a name – Mercuria. To found Mercuria, the basic problems of heat and vacuum need to be solved, because Mercury is close to the sun and has no atmosphere. These problems apply both to the trip there and to the colony itself. Space ships of course solve the vacuum problem nicely by providing an airtight enclosure to live in. Appropriate shielding, including a thin and light reflective coating can in principle solve the heat problem for the craft. Given such a ship it seems natural, after landing it on the planetary surface, to use it as the initial structure housing the colony itself. Later, larger domes can be constructed and underground caves dug.

Some places on the planet are better prospects than others for placing our new community of Mercuria. Water is good to have, for us humans. Luckily water ice is present on the Mercurian surface, so Mercuria should naturally be located there. You might wonder how a planetary surface that regularly reaches around 800 degrees fahrenheit could contain ice – well, there are craters near the poles that are in perpetual shadow, because sunlight hits the pole areas at very oblique angles, shading low points in the craters. Without an atmosphere to provide a hot wind from the mid-day 800° F places into the shaded craters, these craters stay extremely cold. A good place to build Mercuria would be where ice is present in the bottoms of these craters.

Water ice is good to have nearby, yet it wouldn’t do to have Mercurians shiver or even freeze from the cold, especially being so near the sun and on such a hot planet. Warm clothing can be useful but will only go so far. Fortunately sunlight is intense outside the shadows and so the abundant solar energy could be tapped as a source of heat and light, both to warm the community of Mercuria and to support growing crops and algae in tanks.

A good place to collect solar energy would be one that stays lit 24/7 (or the Mercurian equivalent, where daytime generally lasts a year and each year is 88 Earth days long). Fortunately, the poles are not only relatively cool, they also have a few special spots that receive sunlight all or almost all of the time. This is nice because nighttime on Mercury is as long as daytime – another 88 Earth days. One wouldn’t want to be without power generation for that long. Earth’s moon has certain ever-sunny spots on certain mountain tops. They are called peaks of eternal light. The perfect spot for Mercuria would thus be in an icy “pit of eternal shadow” at the bottom of a crater, near a “peak of eternal light” at the top of a neighboring mountain.

Once the new community of Mercuria gets underway, population will likely begin a steady increase. Offshoot communities will soon be needed at other hospitable locations. I say soon because at a population increase rate of 2% per (Earth) year, 100 Mercurians will become a million in just 467 years – and ten billion in another 467 years. Successively less ideal locations will need to be colonized, using successively more well-developed methods for taming progressively harsher conditions. Assuming unlimited cheap solar energy is sufficiently enabling, Mercury is actually a great place to be. Underground caves could be drilled to house colonies because caves keep a steady temperature (on Mercury one would do this preferentially at locations with a human-friendly average surface temperature (well below the blistering heat of the Mercurian day but much warmer than the sub-freezing cold at night). Caves at less ideal locations could be made habitable by cooling them with powerful air conditioners or even warming them with heaters, as colonization technologies improve over the generations. Habitable areas of Mercury will soon become overpopulated, posing a bridge that will need to be crossed, just like on Earth.

Next time: Part 2 – Venus