WHAT'S THE BEST DESIGN FOR A SPACE COLONY?

One day we’ll want a place humans can live beyond Earth. Mars and a number of the moons of the gas giants are prime contenders because they offer lots of space and many of the physical resources we’ll need right there—minerals and important gases locked up in ice or rock. Still, there’s a good chance that our first colonies beyond the atmosphere won’t be anchored to anything big and solid at all. They’ll probably be air-breathing environments floating free in the space between the planets. One of the five Lagrangian points, where the gravity of the Earth and the Moon are in balance, would be a good choice because once placed there, the colony would stay put. It would also be relatively close for purposes of supply, communication and, in the worst case, escape back to Earth.

Though we’ll probably place small-scale habitats in one of those spots to continue learning all we can about space living, I have a feeling that the first real colony of any size outside the Earth will be somewhere else. Like the center of a hollowed-out asteroid.

It just makes sense. We’ll be digging out the asteroid anyway, mining it for metals and anything else we can find. Depending on which rock we pick, it will probably have many of the valuable elements we’d find on a planet without the difficulties caused by planet-scale gravity. Plus man-made hollows inside a metallic rock will have plenty of natural radiation shielding. You can’t overestimate the importance of that outside Earth’s protective magnetic field. There would be drawbacks, though, including the great distance to the asteroids, the complete lack of gravity, and the difficulty of providing good lighting inside a rock.

In his inspirational book from the early 1990’s called The Millennial Project, Marshall T. Savage suggested that the best model for a space colony would be a clear giant bubble with smaller bubbles nested inside. Nice and simple. The outer bubble wall would actually be a double membrane with five meters’ thickness of water between the layers, which would allow sunlight through but block most harmful radiation. As with a hollow asteroid, though, there wouldn’t be any gravity, and we know that human muscles, bones, and organs quickly deteriorate without it. Savage believed this could be solved through a combination of electro-stimulation and exercise in special facilities spun at high speed to simulate gravity, but I have my doubts. A rigorous exercise routine helps the astronauts on the International Space Station, yet they still have to undergo months of rehabilitation when they return to Earth. Even if future space colonists never return to Earth, there are indications that microgravity over long periods of time will cause health problems.

Several concepts for space colonies are designed to spin to produce simulated gravity on their inner surfaces thanks to centripetal force (here’s a great page showing the most popular designs). The Stanford Torus is like a giant wheel, perhaps with one or more large mirrors placed nearby to reflect sunlight into the interior. In the movie Elysium the colony of this design had no roof, so shuttle craft could easily come and go. But there was no radiation protection at all, so it would only be feasible within the Earth’s magnetic field. With the Bernal Sphere concept, areas near the equator would have the highest gravity but it would weaken toward the poles, so there’d likely be a fat stripe of inhabited area with windows near one or both ends to let sunlight in. That’s a lot of mass to spin up considering so much of the surface territory would still have insufficient gravity. The O’Neill Cylinder might be the best design of the three: a large cylinder spinning on its long axis, with lengthwise sections of land area alternating with window strips to provide sunlight (actually O’Neill suggested pairs of cylinders close to each other rotating in opposite directions for reasons of physics I won’t get into here). Unless Scotty comes back from the future to give us the formula for transparent aluminum, like in the fourth Star Trek movie, the windows in the Bernal Sphere and O’Neill Cylinder would require a lot of glass or polymer, and all three of the above designs would probably still be deficient when it comes to radiation shielding.

Here’s my thought: What about using a giant bubble full of air of the kind suggested by Marshall T. Savage, but with an O’Neill cylinder spinning inside it? You’d get the radiation protection of the water (which would let you get away with thinner walls in the cylinder), lots of light, and the extra space in the bubble could be used for zero-g manufacturing and the growing of food crops that don’t mind microgravity. I realize that a wide-open wheel or cylinder wouldn’t work because of high-wind effects from the structure’s spin, but with sharply tapered ends and baffles to break up the flow of air, it should still be possible to come and go from the cylinder habitat into the rest of the bubble. Wind effects would also be less if we settled for something lower than full Earth gravity, thus allowing a slower rate of spin.

What do you think? Problems with friction effects? Static electricity? Give me your thoughts, I’d love to hear them.

It’s by playing around with such concepts that we’ll ultimately find the best solution.

SOUNDS LIKE WE'RE NOISY INTRUDERS IN OUR OCEANS

If you’ve ever explored meditation or been coached on how to ease anxiety, you’ve probably been told to picture a calm ocean view, or maybe even what it’s like to be under the water. You can buy recordings of gentle surf or underwater sounds to help you sleep. We tend to think of the ocean as a quiet place, and it must be especially quiet at the bottom of all that water, right?

Not so. Last July scientists from the National Oceanic and Atmospheric Administration in the US, Oregon State University, and the U.S. Coast Guard used a titanium-shielded microphone to record sound at the bottom of the Challenger Deep, the deepest point of the world’s oceans, eleven kilometres below the surface. The equipment picked up noise from faraway earthquakes, a typhoon that passed overhead, and even the propellers of a passing cargo ship—from eleven kilometres below! Of course, we already knew that whale song can travel vast distances across the oceans, too. Salt water is just a terrific medium for sound waves to travel through, which is probably why whales, dolphins, and a number of other creatures use sound to navigate the sea as well as bringing and keeping their social groups together.

The thing is, we humans aren’t the shy and retiring type. To be honest, we can be pretty loud. And that goes for the things we do in the world’s oceans, especially activities like deep drilling for oil and, soon, even louder seismological exploration to find deposits of oil. It doesn’t take a marine biologist to figure out that the noises we make will be disruptive to marine life over a huge area. Not just the dolphins and whales that use echolocation, but even the small creatures of the sea bed that are responsible for stirring up nutrients from the sea floor that other species need, and even provide dinner themselves for larger predators. Some marine researchers from the UK studied how loud human noises affected Manila clams, brittle stars, and small lobsters called langoustines. The noises made the lobsters stop making their burrows and the clams to shut themselves up tight as a…well, clam. You’ll know how they felt if you’ve ever had a construction company doing roadwork in your neighbourhood, or suffered through a blasting crew using dynamite to get rid of some inconvenient rock. The difference is that we expect to get some benefit from noisy projects like that—lobsters and clams don’t. Worse, we don’t yet know whether sea creatures recover from such disruptions or if there might be serious long-term damage to some species.

Something else could also be compounding the process. The huge amounts of carbon we keep throwing into the atmosphere isn’t just affecting climate, it’s also making the oceans more acidic. There have been concerns that more acidic seawater not only affects creatures that use sound for their survival (like the so-called “snapping shrimp”) but might actually pass sound waves even better, creating a louder ocean. That opinion isn’t held by everyone (see this study from the Woods Hole Oceanographic Institution) but the possibility means a lot more study should be done before we do damage we can’t undo.

What’s the science fiction angle on this? Well, living and working in undersea cities and factory installations has been an SF trope for years, and though we’ve only taken baby steps along that path so far, the depletion of land resources means there’s a good chance we’ll turn to the sea for a lot more than just oil in the coming centuries. Farther down the road, it’s even possible that we’ll make a presence for ourselves on celestial bodies like Jupiter’s moons Europa and Ganymede, or the Saturnian moon Enceladus., which are thought to have oceans of their own, maybe including forms of life. So while we’re learning ways to cut back on our other forms of pollution, let’s make sure we don’t ignore the sound pollution that could be just as damaging in its way. That’s just being good citizens of our planet and our solar system.

You know those neighbours who drive down the street blaring a hip hop bass line that vibrates your windows, and throw loud pool parties until 3:00 in the morning every summer weekend? We don’t want to be them.

THE MARS DILEMMA

This NASA video shows a concept animation of how one proposed Exploration Zone on Mars might work.

An excellent new article in Scientific American describes a meeting last October that gathered together dozens of the world’s most committed proponents of a manned mission to Mars. They hoped to be able to choose the landing site for the NASA Mars mission planned for twenty years from now, or at least come up with a shortlist. They didn’t.

There are a huge number of important factors to consider in the selection: they need a landing site that’s not too high in elevation (or the thin air will hamper the use of a parachute) and not too low (thicker air will hold too much dust kicked up during the rocket landing and cause problems);  a site close to the poles will be too cold and get too little sunlight, plus the rotation speed of the planet near the equator gives an extra boost to a departing spacecraft for the trip home. Producing rocket fuel for the return trip (from water) is essential—some places it would have to be processed from the soil using heat, or squeezed from rocks; places farther north or south likely have groundwater or ice under the surface, but they have disadvantages mentioned above. Areas already studied by the Mars rovers and other craft are well-known, with lots of data gathered over the years, but there’s something to be said for exploring new territory too. The Scientific American article covers all of those issues very well.

But one aspect of the Mars discussion might be even more of a roadblock than the selection of a landing site—the dilemma about microorganisms.

If there is some form of life on Mars—and answering that question is one of the main reasons for going there—there’s the risk that astronaut explorers will disturb some soil or rock, or thaw some ice, and release organisms native to that world which could find their way inside the habitat, maybe inside the astronauts themselves, and eventually back to Earth. It’s unlikely that precautions and decontamination measures would be 100% successful in preventing that, and there’s no way to know what kind of risk such life might pose to forms of life here on Earth. An alien ebola for which our immune systems have no defence? That’s an alarmist view, but not impossible.

Then there’s the other side of the coin: protecting Mars from contamination by us.

The United Nations Outer Space Treaty of 1967 forbids the harmful contamination of celestial bodies. Every spacecraft that goes to Mars has to undergo (and survive) rigorous sterilization procedures, which accounts for a substantial part of the costs of such craft. And that’s just metal and circuits—what about living bodies? Some researchers claim that the human body supports ten times as many bacterial hitchhikers inside and outside than the number of the body’s own cells. How can we possibly be sure of not leaving some of those bacteria behind on Mars? If the planet is utterly barren, the risk that our Earth bacteria might survive and spread might not seem like a severe consequence (except for violating the space treaty). But what if there is life on Mars? It will probably be in the form of microorganisms inhabiting the subsurface ice and damp soil, managing to survive under very challenging conditions. There’s a significant chance that the Earth bacteria we unleash could be deadly to Mars life outright or simply provide too much competition for scant resources.

We might discover the first known form of life elsewhere in the universe, only to find that our explorations have condemned that life form to death.

There’s an outside chance that we could dodge these problems with one very carefully regulated visit to the Red Planet. There’s no chance at all that we can ignore them if we ever establish permanent habitations there. So before we ever colonize other celestial bodies, we’ll have to decide whether it will be a one-way trip for the colonists (to prevent the contamination of Earth) and whether or not we have the right to spread our own form of contamination throughout space.

If you’ve read many of my blog posts you’ll know that I think it’s critically important for humanity to establish a presence beyond Earth—our small planet is just too fragile, and we’re too vulnerable here—but it may be that we’ll have to confine our migration to places that are unquestionably devoid of life.

On one hand we’d love to know that we’re not alone—that life has arisen elsewhere in the universe, but if it has, we may have to protect it from ourselves by staying away.

A dilemma indeed.

YOUR BRAIN ON SCIENCE FICTION

OK, that title may be a touch misleading because this isn’t a neurological essay. But I do believe that reading science fiction is unique in its benefits. Let’s start with reading in general, although lately the picture isn’t pretty.

Every year the Pew Research Centre surveys the level of readership among American citizens. In 2015 28% of Americans did not read a book, in any form, and the numbers are getting worse. Certainly we do a lot of reading online, especially social media, and maybe a lot of that is time we would otherwise have spent reading books. Of course, television has often been blamed as the enemy of book reading. When asked about it, people will complain about their trying work day and say, “I just don’t want to think for a while—I want to turn my brain off.” I’ve caught myself saying it (but then I read all day long, in some form or other).

Obviously our brains aren’t switched off when we watch TV or movies. We’re still analysing plot details, observing the characters’ behaviour, piecing clues together, absorbing setting elements of each frame, and predicting the action to come. We’re empathising with the people we like, mentally arguing with those we don’t, and whether it’s reality TV or fiction, our emotions are getting a workout. We face pop-up ads on the screen and, if we choose to watch commercials, a bombardment of information that we automatically begin to judge for its veracity and usefulness, enticements that we must balance against our own resources, and a whole range of other things that make our brains work pretty hard.

In reading a book, there is similar interaction with characters and plot, plus we also have to process written words and imagine what they describe (but don’t have to process the extraneous content included in a video picture). We  allow the interpretation of the words to trigger responses from our senses to a degree. But we don’t have to endure commercials—not even product placements, usually. We have to turn pages but we don’t have to master a remote control. We can skip or re-read any section we want, with no more effort.

Which one is really the most work?

The majority of people are readers, and since reading in school has been proven to encourage a lifelong reading habit (generally) and more people are attending college or university these days, the demise of the book is probably still a long way off.

Articles like this one cite research to claim that reading for pleasure makes us more satisfied with our lives, better able to make decisions, more connected to other people and more empathetic (by understanding that they share our experiences and feelings—take that, Facebook), with greater awareness of social issues and cultural diversity, higher self-esteem, and the list goes on.

What does this have to do with science fiction (apart from encouraging more readers overall)?

Well, reading for pleasure has been proven  to give us much greater general knowledge, and readers of science fiction are exposed to a huge range of extra information from every field of science, of course, but also philosophy, history, religion, and even art, as SF stories explore alternate timelines, alien cultures, and possible futures. I don’t think any other art form is as good at broadening our thinking and encouraging our imagination. It can both illuminate and inspire, warn us off and spur us on. Unlike most other forms of art and entertainment, the potential of SF to take us beyond the confines of our normal lives is almost limitless.

I will admit that reading SF is a little more work.

But it’s worth every bit of it.

VACATION AMONG THE STARS

Poster from NASA Jet Propulsion Laboratory

Take a once-in-a-lifetime vacation among the stars!

Or at least among the planets. And moons. And asteroids.

OK, not quite yet. But we can go a long way in our imaginations, especially with the help of the NASA Jet Propulsion Laboratory’s new series of travel posters.

The travel posters are the work of JPL’s The Studio: “a design and strategy team that works with JPL scientists and engineers to visualize and depict complex science and technology topics. Their work is used in designing space missions and in sharing the work of NASA/JPL with the public.” And the posters are available for you to download or print off free-of-charge to help your imagination take you all over the solar system and beyond. Fine print at the bottom of each poster explains the known facts behind the artists’ inspiration.

On planets like Jupiter and Venus, we’re only likely to be able to establish a human presence in their upper atmospheres—Jupiter’s gravity and atmospheric density would crush us any lower than that, and Venus’s high atmosphere is its only zone with human-friendly temperatures and survivable pressure too. But what about a Jovian balloon ride or a visit to a Venusian cloud city?

Who knows what sights can be seen from dive suits or submersibles in the ocean under the ice of Jupiter’s moon Europa? (Scientists and SF writers have considered Europa one of the most promising places in the solar system to find extraterrestrial life.) Or maybe an exotic boat ride on one of the liquid methane lakes of Saturn’s planet-sized moon Titan is more to your taste. From there you could skip over the rings to Enceladus and gaze at the famous geysers.

If we ever get the hang of interstellar travel you might check out the twin suns of Kepler 16-b (and pretend you’re on Tatooine with Luke Skywalker), or the red sun of Kepler-186f (like Krypton—do you think we yellow-sun-dwellers might gain super powers there?), or try skydiving on HD 40307g with its extra thick atmosphere. If you’re a true party animal and night owl (or an actual vampire who shuns the light of day) then the place for you would be PSO J318.5-22 which looks to be a rogue planet without any nearby star to give it light. Neverending nightlife!

Sure, a lot of this is speculation and all of it involves flights of fancy, but these free posters from NASA could be a great addition to the bedroom of a young budding astronaut. Or equally good for grown-ups like us who still allow our inner child to dream and dream big.

SMALL CAN BE A BIG GAME CHANGER

Image ID: 50753825Copyright Kts | Dreamstime.comhttp://www.dreamstime.com/kts_info

In the 1966 movie Fantastic Voyage a team of scientists in a special submarine are shrunk down to molecular size and travel through the bloodstream of a scientist trying to save his life. I’ve always loved the movie (and the novelization by Isaac Asimov) but there’s no sign that shrink-ray technology will be developed anytime soon. So I wrote a (so-far unpublished) novel about how such a thing might be done with plausible tech—you can read a prequel short story to the novel here.

But while we haven’t developed a shrink ray and probably won’t, medical nanotechnology has been advancing in other ways. Nanotech is considered to include devices between 1 – 100 nanometres in size, with a nanometre being one billionth of a metre. That’s small! And if we can master materials at that scale, the possibilities are indeed fantastic.

Current research includes very promising experiments with silicate particles covered in gold and with iron particles encased in a polymer. The idea with both is that they can float through the bloodstream and (hopefully) be induced to concentrate at the site of a diseased body part, like maybe a cancer tumour. Then they’re heated by non-harmful laser light or other methods until the shell/coating breaks down and therapeutic drugs are released exactly where they’re needed most. Such a system has terrific potential for delivery of medicines, yet it’s still primitive compared to what’s being imagined.

How much better if the nano-devices could be steered directly to the site of the disease? Especially if other nano-bots had already traveled through the patient’s entire body and mapped it down to the smallest capillary? What if we could program nano-drones to patrol the bloodstream and spot foreign bodies like bacteria and viruses that don’t belong, perhaps even attack and destroy them with chemicals or heat? Our biological immune system already does the same thing, but we know that it sometimes needs help. Those same drones could be sent to remove plaque from the linings of our arteries and veins, preventing high blood pressure and heart disease. As we age, much of the deterioration of our brain and certain other organs can be blamed on a buildup of a substance called lipofuscin in our cells—like trash clogging the streets of a town with no more room in its landfill. Specialized lipofuscin-removing nanodevices might prevent or even roll back many of the harmful effects of aging.

It would be even better if smarter nano-bots could find damaged tissues and repair them, not just protecting us against new disease but also healing the damage left by old infections. With enough advancement in the development of both artificial intelligence and nano-manufacturing we could eventually have germ-sized robotic doctors patrolling our bodies, keeping us young and healthy.

Research is exploring all of these possibilities and more, and although there’s no way to know how soon scientists will succeed, we should start planning now. Medical nanotechnology will eventually mean huge shifts in the allocation of health care resources, but even more importantly, it will result in a much longer human lifespan and much lower death rates from disease. Imagine if most humans survive for two or three hundred years (or even longer) and are in good health and able to do productive work for nearly all of that time. Population control will be unavoidable. Our whole system of older workers leaving the workforce and making job openings for younger people will take too long. Forget about the “retirement years”—no society can afford to support unproductive members in large numbers for many decades, and anyway we’ll need to have meaningful tasks to perform throughout our extended lives, if only to avoid death by boredom.

Such an increase in health and longevity could result in the most amazing progress humanity has ever seen, or the worst crises of inequity and deprivation. So while we look forward to the good health and long life, let’s plan ahead to make sure we can all enjoy everything that promise entails.

Remember what Spock said: “Live long and prosper.”

There’s more great reading on this subject here, here, and here.

AAAAH, BUT NOT AWE

NASA New Horizons image of Pluto's moon Charon

I recently listened to a podcast interview with science fiction writer David Brin in which he proclaimed that the past year was the best year ever for space exploration.

He made a good case for the claim: perhaps the biggest space story of the year was the New Horizons spacecraft’s flyby of Pluto in July that offered some truly stunning photos of our one-time ninth planet. But it was far from the only story. After visiting the asteroid Vesta a few years ago, NASA’s Dawn spacecraft went into orbit in March around the other major dwarf planet in our system, Ceres, the largest object in the asteroid belt. The European Space Agency’s Rosetta craft continued to follow the Comet 67P/Churyumov-Gerasimenko in its path around the sun, even briefly regaining contact with its lander Philae on the surface of the comet. A Japanese probe successfully made orbit of Venus (on its second try) and an Indian Mars probe was a thorough success.

Private space companies had a couple of setbacks, but significant successes too. Blue Origin was able to safely land a rocket booster on its tail, like something out of 1950’s space movies, and then SpaceX topped that by launching eleven satellites using its Falcon 9 rocket which was then successfully landed back on the launch pad for re-use. That technology should reduce the cost of sending things into space by a huge margin, which could well kick-start a revolution in the exploitation of space.

It’s been an amazing year.

Did anyone notice?

Oh, I know there were always some trending stories on Facebook and Twitter, but did anybody except science nerds and science fiction writers actually get excited—really celebrate the milestones being achieved? I don’t think so, not to the extent that they deserved. It seems as if, in these times when almost the whole of human knowledge is available to us through the internet, we take for granted that everything worth knowing is either already known or soon will be. Through digital media we’re constantly bombarded with new discoveries (many not yet substantiated) in the fields of medicine, physics, biology and, yes, astronomy…so the extraordinary achievements of space engineers who manage to hurtle high tech robots over ten-year-long trajectories to planets nearly five billion kilometers away just become more of the same. Expected. Not quite routine, but not life-altering. Not landmark events in the fabric of our lives.

Or maybe I’m blaming the wrong thing. Maybe we’ve become so used to seeing science fiction movies and TV shows with exceptionally realistic special effects that the actual pictures of a real place like Pluto fill us with aaah but not awe. We see rugged Plutonian plains of nitrogen ice, geysers on Jupiter and Saturn’s icy moons, rocky planetoids spinning in the vastness of space, and we say, “That’s cool” and move on to an article about the next iPhone, or ads for the next model of aerial drone. I don’t really know the reason. I know that in the middle of the last century each new achievement in space made us think of gleaming cities with tube trains or monorails, passenger rockets to Mars, and fantastic floating colonies in high Earth orbits. Now they only lure our minds away for a few minutes from thoughts of climate crises, terrorist threats, and burgeoning epidemics.

When did hope and wonder give way to fear and gloom anyway, and why? Hope and wonder are a lot more fun.

The next time you see photos of a new space discovery, take a few moments to really picture the scene. Picture the incredibly talented team of dedicated people that made it happen, the vastness of space and the incredible unlikeliness of the amazing objects out there, and our being alive at this time in history to witness it. Let the wonder really take hold.

Of that feeling are bright futures made.

OUR BRAINS CONTINUE TO SURPRISE

Two news stories about the human brain are worth passing along this week.

The first is a potential breakthrough by Australian researchers in the treatment of Alzheimer’s disease. One of the primary causes of Alzheimer’s is the build-up of what’s known as amyloid plaques between the nerve cells of the brain (neurons) that interfere with the transmission of signals. Drug-based treatments for Alzheimer’s have had limited success partly because the body’s own blood-brain barrier, meant to protect the brain from invaders, does a good job of keeping out helpful chemicals too. The new treatment involves using focused therapeutic ultrasound—gentle sound waves that nudge the blood-brain barrier open to help the body’s clean-up crew (microglial cells) to remove the offending plaques. So far, test results in mice have been very promising, restoring 75% of memory function without causing damage. That’s still a long way from curing humans, true. But having witnessed the ravages of dementia up close in the last years of my mother’s life, I appreciate any good news in the fight against it.

The second story involves a new calculation of the data processing capability of the human brain. Signals pass between neurons via special structures called synapses, so it’s not hard to understand that the ability of a neuron to pass signals will be affected by the number and size of the synapses it has. It was thought that there are only a few different types and sizes of synapses in our brains, but when a team led by the Salk Institute recreated brain tissue down to the nanometre scale for the first time, they discovered that synapses change according to how they’re used, and how often. The Salk scientists and their partners calculated that there could be as many as twenty-six different categories of synapses, adjusting themselves as needed, which goes a long way toward explaining how the brain accomplishes so much using so little energy (the power consumption of a dim light bulb, they say). But it also means that our brain’s capacity for storing information could be ten times greater than previously thought—possibly in the range of a petabyte (a million gigabytes) which is the equivalent of all the storage in the World Wide Web.

Are you feeling impressed with yourself yet?

A long-lived urban myth suggested that we only use about ten percent of the capacity of our brains. That claim has been thoroughly discredited by neuroscientists, but the Salk Institute findings have to make you wonder if there isn’t a way we could somehow make even better use of all the brainpower we have. It’s a vast amount of storage, yes, but what if we could improve our information processing, filing, and retrieval systems? For one thing, we might never again lose our car keys (!), but we also might have less and less need for digital computers. Since synapses respond to need, picture flicking a mental switch to turn on “mathematics mode” or “language mode” to temporarily divert cognitive resources to a specific task. We could be specialized  geniuses on demand! The idea of someday using a human brain to store secret data archives (like in the TV show Chuck or the movie Johnny Mnemonic) seems more plausible too.

But doesn’t it also make you wonder if there aren’t other potential capabilities within our brains that we’ve either forgotten how to use or just haven’t learned yet? Most scientists would scoff at the idea of so-called “paranormal” powers like telekinesis and telepathy, and most science fiction writers relegate such things to fantasy instead of SF. I’m not so sure. For one thing, I accept that there are dimensions of existence that we don’t currently perceive, but mathematicians and physicists readily include them in their theories about the universe. And I can accept that the universe includes an underlying level of information, call it what you will. Human beings don’t normally tap into such things because we haven’t needed to for our survival, but that doesn’t mean it’s beyond our ability if we only knew how.

I believe that each new discovery about the human body and mind in physical terms leads to a deeper understanding of ourselves in a holistic and even philosophical context. So news stories  like these reinforce my conviction that the human adventure is far from over and there are many wonders yet to come.

ADAPTING HUMANS TO OTHER PLANETS, PART TWO

In my last post I speculated about how we might adapt ourselves to the environments of other planets rather than trying to terraform them or forever be confined to enclosed settlements and space suits. I used Mars as an example of an “earthlike” planet we might consider colonizing.

A Mars-type planet would be an easy challenge compared to others like Venus. The Venusian atmosphere is also mostly carbon dioxide but the air pressure at the surface is ninety times that of Earth, like being a thousand meters deep in the ocean. We know that fish and other creatures can exist at those depths, and some whales can dive even deeper for a time—so it’s not inconceivable that our bodies could be adapted for it (maybe even encouraged to grow a hard shell?) But again, we wouldn’t be breathing—air at that pressure is basically a fluid. We’d have to get oxygen and/or energy another way. And Venus is hot—hotter than Mercury—about 460 C at the surface. If there is any part that might be relatively hospitable to humans it would be the upper atmosphere, about fifty kilometers high, where the temperature and pressure are nearly Earth-normal. There are obstacles though: winds over 300 kilometers per hour and clouds full of sulphuric acid!

OK, so maybe Venus-like worlds will be beyond biological adaptations and require either full space suits or at least extensive mechanical adaptations.

Gas giant planets don’t hold much attraction as homes-away-from-home, but many of their moons might. With a tough enough skin and a metabolism that uses chemosynthesis instead of air-breathing, maybe we could survive in a near-vacuum, but it’s hard to imagine that we could ever adapt our bodies to temperatures that can freeze water as hard as granite. On Jupiter’s moon Europa, for example, the temperature at the equator (you know, the beach resort zone) averages about -160 C. Where there is a possibility of survival, however, is under the icy surface in an ocean of water. Someday we may create humans who can function as aquatic creatures, in which case our own planet’s oceans will provide a vast amount of space to explore and inhabit.

There’s a chance that we’ll discover planets elsewhere that are almost identical to Earth and already support life. In that event, our problem will be that some of the life, particularly microorganisms, could be utterly hostile to humans. Deadly germs or bacteria. Then we’ll need to either adapt our immune systems to cope with the pathogens, or adapt our whole bodies to co-exist with the alien organisms (although, to be accurate, we’ll be the aliens).

I haven’t even touched on the whole area of technological enhancements to the human body—turning us into partly-cybernetic organisms, or cyborgs. Maybe in another blog someday. And, of course, there are huge philosophical and ethical questions involved whenever the question of bio-engineered humans is raised. Is it too big a risk? If such genetic engineering had to occur at an early age or even at the fetal stage, could we make such decisions for our children? Most of all, how much can you change someone before they’re no longer human? We don’t mind the idea of fictional superheroes transformed by a radioactive spider bite or gamma radiation—the reality might evoke feelings that are quite different.

For now, I’m content to leave this as an exercise of the imagination, but the time will come when we achieve the capability for such things. I hope we’ll have resolved our questions about it by then.

COULD HUMANS BE ADAPTED TO OTHER PLANETS?

In a recent post I mentioned that there are huge amounts of water elsewhere in the solar system—much more than actually exists on Earth. And when scientists assess the potential of other star systems to host life, the foremost yardstick they use is the presence of water, especially liquid water. Where there’s liquid water, there could be life that we would recognize. So a planet orbiting its sun in the so-called “Goldilocks zone” (not too hot, not too cold) might have liquid water and thus be capable of supporting life. Maybe.

This fairly narrow view isn’t so much based on the idea that we only want to meet aliens that look like us (as in most Star Trek episodes) but more because we want to visit places that will present the fewest obstacles to our survival there. Lots of oxygen in the air would be nice. Clean drinking water. Reasonable weather. Gravity that doesn’t make us feel like we’re wearing lead overcoats.

You’ve probably heard news stories about “earthlike” planets being discovered around other stars. That description usually only means that they’re rocky planets instead of gas giants, and they’re not frozen or roasting hot. That’s it. Everything else about them might be far different from Earth—we just don’t know because those planets are too far away. We do know about the planets in our own solar system, and by the above standards Mars would be considered earthlike, except a little cold. But we certainly can’t live there. At least, not yet.

For humans to survive on another planet—in this solar system or any other—there are three ways to do it. The ways that get the most attention are: 1) building habitats (even domed cities) that will protect us from the planet’s hostile elements and enclose a simulated Earth environment; and 2) change the planet’s entire ecosphere into a close approximation of Earth’s—what is called terraforming. Enclosed habitats will always be very restrictive and costly to expand, while terraforming some place like Mars would take thousands of years.

The third option is to change the human body itself in ways that will adapt us to the alien environment.

On Mars that would require quite a few changes. We know that people can adapt to colder climates (especially over a number of generations) but even Mars’ most hospitable climes would require genetic tweaking to rev up our metabolism, increase blood flow, and grow much thicker layers of insulating fat under our skin. We’d have to grow a tougher skin, too, with closable orifices—even skin pores and tear ducts—to prevent the low air pressure from boiling away our bodily fluids. These things aren’t inconceivable as we get better and better at gene splicing—we’d find organisms with those traits here on Earth (perhaps creatures that live in extreme environments) and splice the necessary genes onto our own genome. Even so, a few more mechanical implants might also be in order, like heating coils in our nostrils to warm our inhaled air!

Mars’ atmosphere is mostly carbon dioxide with very little oxygen, so to avoid the need to carry air with us we’d have to either re-engineer our body cells to use some energy source other than oxygen, or get assistance from something that can make the oxygen we need from CO2. Plant life uses photosynthesis to produce food energy from carbon dioxide and water using sunlight (but it’s slow). Creatures that live around deep-sea volcanic vents use chemosynthesis instead, getting their energy, not from sunlight, but from the oxidation of compounds like hydrogen sulphide gas. Giant tube worms, crabs, clams and others are filled with proteobacteria and archaea—some of the earliest life forms on the planet—which replace their usual digestive tracts of stomach, intestines etc. And we know many kinds of algae and bacteria that can produce oxygen from materials in their environment, including the bacteria Methylomirabilis oxyfera which extracts oxygen from nitrates in the river mud where it lives. Since our bodies already carry around hundreds of types of bacteria that help keep us alive, it’s not a huge stretch to believe that a few additional species might help us exist on other worlds.

Mars would be one of the easier planets for us to adapt to. And, of course, there’s the whole ethical question of whether or not we should tinker with the human body to that extent at all. But that topic will have to wait until my next post. In the meantime you can read some other people’s thoughts about this here, here and here.