Archives For aliens


Another day, another study identifying more potentially habitable worlds in the Kepler data, this time by professional astronomers and volunteers called the Planet Hunters who discussed their planet detections on a specialized message board system called Talk. What they found was that more gas giants orbited stars in their habitable zones than initially thought, giving real evidence for the hypothesis that while alien Earths could be somewhat rare, moons orbiting alien Jupiters and Saturns may be a fairly common habitat for extraterrestrial life. Trouble is that we can’t see these moons or detect the wobble of the planets they orbit, so we don’t know how many of them there are, how big they are on average, and their likely composition. However, we do have very good reasons to assume that they could be there since gas giants in our own solar system are swarmed by moons of all shapes and sizes, and some are very possible hosts to life.

So one would think that a moon big enough to hold on to an atmosphere that’s not too dense or composed mainly of greenhouse gases in an alien star’s habitable zone would have liquid water in significant quantities. Even better, it would feel the gravitational tides of a gas giant that would in effect knead its interior, promoting volcanism, circulating rich organic matter that could either kick start living things or fuel them. Think of Io but more subdued and covered with oceans and small continents, or Titan without the mind-numbing cold. It could be a perfect habitat, and given billions of years, maybe even evolve intelligent life. But there’s a potential problem here. Typical solar system formation models dictate that rocky worlds form closer to a star than gas giants, so to be in the habitable zone of the vast majority of stars out there, alien Jupiters had to drift into these orbits, pushing out rocky worlds and reshuffling their siblings. What would that do to their moons? Would they be collateral damage in the upheaval of the solar system?

Ideally, the immense gravity of these gas giants would push planets aside as they spiral into the habitable zone and their clutches of icy rocks would slowly thaw to host oceans and fertile land for life to start taking hold. But again, the only way we’ll know this is if we build bigger and more powerful telescopes to detect their presence and hopefully one day resolve them as pixels for a quick spectrographic sniff of their atmospheres. Maybe, just maybe, decades from now, a future astronomer and a crew of enthusiastic volunteers will be looking through a data set collected by the latest planet hunting telescope and find a little bluish pixel next to a gas giant, or readings of a gas pointing to a stable biosphere, like oxygen from a recently discovered alien moon. It won’t be Earth 2.0, but it will be just as important, and we’ll be able to look up at the night sky knowing that we’re not alone because somewhere, a weird world with a killer view of a turbulent gas giant is home to something that can look back at Earth, even if it won’t wonder about us…

See: Wang, J., et al. (2013). Planet Hunters. V. A Confirmed Jupiter-Size Planet in the Habitable Zone and 42 Planet Candidates from the Kepler Archive Data arXiv: 1301.0644v1


galaxy in hands

Individual humans aren’t much of an impact on nature by themselves. Considering the sheer size of the Earth and our finite life spans, one would think we have very little effect on our world. But there are a lot of us and in the last thousand years, we’ve dammed or diverted many major rivers, built artificial islands, pumped billions of tons of greenhouse gasses into the atmosphere, lit up the the night skies with our networks of cities, put a smattering of objects in orbit, and managed to connect the world with fiber optic cables stretching across the ocean floor for thousands of miles. We’re slowly but surely changing the world, and if we were gone tomorrow by some bizarre happenstance, it would take nature centuries to truly erase the mark we left so far. That’s why some scientists started calling the modern age the Anthrophocene, to reflect on how we changed our planet while developing a fully fledged civilization. And space writer Ray Villard ponders whether we could know if a similar temporal designation may apply to the universe itself after reading a paper by a theoretical physicist speculating on whether any species grow powerful enough to alter entire galaxies, doing what humans do on a scale many orders of magnitude greater and involving entire solar systems instead of cities or islands.

Here’s the question. If a species old enough amasses enough technological prowess, would it one day have to manipulate stellar structures big enough for another sufficiently advanced species to notice? This idea is a cornerstone of the Kardashev Scale by which such powerful creatures would register at Level 3 while we are barely even on the chart. For the time being, let’s leave aside the questions of how likely it would be for aliens to evolve the intelligence necessary to build massive interstellar spacecraft and continue to survive and thrive for millions of years as they roam the stars. Maybe they’re just really lucky and have such a passionate vision, they banded together and made it their duty to reach beyond their own solar system. But how far would such a species reach? After all, a galaxy the size of the Milky Way is vast, and to modify it on a noticeable scale would require that the aliens in question manipulate tens of billions of stars. They’ll need trillions of intelligent robots doing their bidding across thousands of light years and executing complex orbital maneuvers that would sync their efforts to a sequence of events planned to last millennia. And they would need to somehow collect all the energy they would generate in this elaborate process. How would they even try to go about that?

Well, if we get very creative for a second and think back to a paper arguing that powerful aliens could draw a lot of energy from stellar mass artificial black holes, we could extrapolate further and make the leap to dark matter being the unseen influence of extremely advanced technology which keeps galaxies rotating around a central supermassive black hole which is periodically fed for a power boost, an artificial quasar of sorts. Most of the energy wouldn’t be generated by the accretion disk in the galactic core, however, it would come from the quickened rotation of the galaxy. So imagine the Milky Way or Andromeda as giant turbines being ran by some insanely powerful alien civilization which channels the enormous currents generated in the process to power warp gates and supply its sprawling empire, an empire so huge we may never be able to detect it. Is this an idea we could actually use in SETI? Probably not, not only because such a phenomenon happening would be so extremely unlikely as to be practically impossible, but because we haven’t a clue as to how this would work and find any support for a species capable of manipulating an entire galaxy as their power grid. How would an astronomer find something we can’t even really conceive of beyond wild, random speculation?

Kardashev Level 3 entities should technically be some of the easiest alien civilizations to notice because an entire galaxy could give us clues to their existence and we can survey a whole lot of galaxies. But their means of altering these cosmic objects would have to be so far beyond us, we may well have seen a myriad of such powerful and technologically advanced aliens in public Hubble image galleries and don’t know it. Maybe we’ll never for sure know if these creatures exist or not. Though it may be fun to think about how exactly they would pull off the feats we usually tend to attribute to them. Who knows, maybe it would inspire us to start a mega-engineering project of our own to see how far we can advance our own technology in the process?


Since a few imprecise observations of Phobos, there’s been an elaborate theory that this tiny little moon was really not as natural as it may seem at first glance, and it was made by an alien species visiting Mars while making its way through our solar system, or an artifact of a lost civilization that might have once existed on the surface of the Red Planet and built the temple complex at Cydonia. Of course a little reading shows that the observations were corrected decades ago and that while Phobos is porous and is most likely a rubble pile of a moon, it’s very much a natural object as far as we can tell. But on the other hand, thinking about Phobos as some sort of massive, generation ship suddenly made me realize that hollowing out an asteroid and giving it some powerful engines was actually an really neat idea for a quick assembly of a massive spacecraft. Carve out some tunnels deep into the rock, reinforce them with extremely strong plastics and alloys, fill them with a branching network of inflatable bases, hook up a few reactors to power massive ion engines, and voila! You have a massive craft ready to explore an attractive exo-planet, or possibly get away from your dying one…

Even the craft construction methods aren’t necessarily all that complex. You just need to find an asteroid, and you’ll have plenty to choose from in any solar system, and using rockets, slip it into orbit around a planet from which you’ll launch spacecraft carrying all the equipment to be placed into it. An asteroid riddled with caves is pretty much ideal, providing plenty of places to anchor and inflate living modules which could then be hooked up to power generators like self-sustaining nuclear reactors and RTGs hidden behind tons of rock and heavy shielding with relatively little effort. The hardest part would be assembling big enough ion engines to embed them deep into whatever you want to be the back of the asteroid spaceship. After the habitats are inflated and life support systems are running just fine, crew your craft, turn on the engines, and slowly accelerate over the next several years into deep space. No need to run enormous factories for years on end to crank out tons and tons of metal or kevlar sheeting to be assembled into vast, aircraft carrier sized spaceships when you already have an asteroid the size of a small suburb at your disposal. Extremely low gravity will obviously be a problem but you’ll have protection from cosmic debris and the brunt of the radiation which fills the universe.

Having established that an asteroid turned into a relatively cheap spaceship is not an impossible concept in the least and might actually be a great shortcut for a species eager to expose deep space but not keen on a commitment of massive manufacturing capacities to the task, let’s get back to the idea of Phobos being such a craft and who could’ve built it. Maybe the Martians fled as their air got thinner and more toxic, and their seas dried out into barren red deserts? Seems very unlikely since early Martian oceans would’ve been hypersaline and hospitable only to microbial life. Even if these microbes had the potential to evolve into an intelligent and complex species, it’s overwhelmingly unlikely that they would’ve hit on the right combination of mutations and selective pressures to produce a species which could build civilizations and eventually launch itself into deep space to escape the dying world quickly enough. Evolution is a messy process and timelines could vary from environment to environment, producing major changes in just a few generations, but considering that out of a wide variety of life capable of intelligence here on Earth only one species has ever built spacecraft during the entire 3.5 billion year history of living things, it’s hard to declare that on another world, a billion years would be plenty to go from basic photosynthesis to spacecraft. We have no evidence that this could happen.

And if it did, what would it imply about us? Mars dried out billions of years ago and even if we are generous in assuming that maybe there was underground water than an intelligent species could’ve somehow utilized, a geologic shutdown of the planet over a billion years ago would’ve signaled a time to leave. So let’s say, that’s when they packed up and left Phobos behind for one reason or another as they readied their space arks. Did they go to settle our idyllic blue planet? Hard to say. At the time, Earth was a desert with green oceans which were saturated with iron and volcanic dust. It would’ve hardly seemed very appealing since its air was thick with noxious gases, oxygen was almost nonexistent outside the seas, and the entire world would’ve looked like a dusty, brownish spheroid punctuated by green splotches of liquid. Not exactly the most attractive world for an intelligent species looking for another place to live. Maybe it would’ve sufficed for them but they either left for a more appealing place or went extinct here since we haven’t exactly been finding billion year old cities filled by countless Martians. So if Phobos is so unlikely to be a Martian relic, that only leaves us with another species that could’ve built it and that species had to have come from another solar system, perhaps in the very distant past when Mars was still an attractive, habitable world, the life-friendly jewel of the solar system.

But there are problems with that theory as well. Detecting a Mars sized planet from another solar system is a task not to be taken lightly and require some serendipity and a lot of patient scanning for a transit so an alien species could detect that it may have been habitable. And if they hollowed out an asteroid to get here, we can estimate that they must’ve come from a room just down the hall from us, astronomically speaking. The trip in such a craft would take thousands and thousands of years otherwise, if they even managed to notice Mars in the first place. Though we could just put all this guesswork in proper perspective and note that from what we have seen so far, there’s no indication that there’s anything artificial about Phobos and that it’s just a battered, porous piece of rock orbiting Mars, and which will eventually fall to the surface and create a long, big crater as its orbit becomes unstable in the relatively near future. But hey, all the guessing about alien civilizations and a possible legacy of Martians in our solar system was fun, huh? And the concept isn’t even close to impossible when we consider the technical details, right? Alas, we can’t simply state that because something is possible it must have happened. We can only go by the evidence, and the only evidence we have says that Phobos is a moon and nothing more than that. And unless that evidence changes, that’s what it should remain.


Traveling quadrillions of miles in a flying saucer to kidnap a random human yokel, perform all sorts of grizzly, invasive and hideous experiments on him or her, then do a total memory wipe and restore everything back to its seemingly rightful order so the victim doesn’t even know anything’s amiss, takes a lot of work and practice. This is exactly why aliens practice their abduction techniques before they can start a career in astrobiology…

Now, what amazes me is how someone could stay asleep through such brutal display of incompetence at the switchboard. Does the tractor beam also come with a sleep ray option? Also, far be it form me to question an advanced alien species capable of interstellar travel, but maybe it would be a wise idea to invest in some sort of labeling scheme? Just a humble suggestion from a primate with an over-clocked monkey brain.


aliens vs. god, the rematch

February 28, 2009

Weird Things readers know that I haven’t been too kind to the ancient astronaut myth which holds that humanity was either created, or guided by the advanced technology of ancient alien species. I’ve called it highly improbable and rejected the idea of alien intervention in our affairs and monument building both on Earth and on other planets of our solar system. But as strange as it may seem, tales of alien creators can play a useful role during a discussion about the scientific method and plausibility in today’s world.

annunaki tablet

According to a recent Pew poll, some 63% of Americans believe that animals and plants existed in their current form since their appearance or were divinely guided. The analysts politely state that “evolution is being debated.” Under no obligation to be as nice, I’ll put the real implications of this poll in black and white. Almost two thirds of the American public believe that digging for fossils and sequencing DNA to compare animal species to each other is a quasi-religious idea while magic is a perfectly sensible explanation of how living things came to be the way they are today. When we compare these findings to similar international surveys, we find that the U.S. is dead last in the Western world in its population’s acknowledgment of science. So if magic could be a perfectly reasonable explanation for the development of living things, why not aliens?

Even though the probability of us being born in an alien lab are zero to nil realistically speaking and the speed with which life arose and spread on our planet seems to indicate that organisms can emerge given the slightest source of food and solvents, it’s not completely impossible. The alien astronaut theory is so convincing to many precisely because it doesn’t violate any laws of physics, biology or chemistry. It’s like a story about a guy down on his luck deciding to spend a few dollars on a lottery ticket because that’s all he has left and winning the $375 million jackpot the next day. The odds? Staggeringly against it. Does it violate any known law or scientific rule? Not at all. Now a guy down on his luck praying for $375 million and having this money fall into his backyard from a cloud overhead like mana from the heavens? Not going to happen.

Yet, people who would argue that humans were designed by aliens are considered freaks while devoted creationists who believe that humans were crafted by magic either from dust or by the metaphysical processes only a deity knows how to invoke, aren’t just considered saner, they’re the norm about 63% of the time. Interestingly enough, creationists can and do apply Occam’s razor to stories about alien designers but leave it behind for magic when it comes to questions of evolution, genetics and biology.


measuring alien intelligence

February 6, 2009

Turn on the TV or go to the movie theater and chances are that every alien civilization you’ll see will be hundreds if not thousands of years more advanced than us and will regard humans with the same condescension we usually reserve for our cave dwelling ancestors. But movies are just our fantasies. How smart would real aliens be and what would they make of us, our culture and our technology? Could it be that we’re actually quite an advanced species in our own right and most aliens we meet will be comparable to us?

alien city

Now I don’t say this to stroke our egos. I say this because most of us have a rather skewed idea of intelligence after the highly toxic effect of Victorian arrogance that is still being exorcised by biologists, archeologists and anthropologists. When we talk about cave dwelling humans right before the dawn of farming and civilization, our dismissive attitude is misplaced. They weren’t inferior to us in any way, shape or form. Sure they didn’t have the benefits of modern science and education some 30,000 years ago, but biologically speaking, they were identical to us. We and the cave dwellers are the same species, separated only by time and minor genetic drifts of natural and sexual selection. If anything, they got us where we are today.

And of course, it all started with a genetic fluke. Broken base pairs of the MYH16 gene gave us much bigger skulls and allowed our brains to grow, developing our current intelligence. In the future, our heads aren’t going to swell to immense sizes and we’re not going to evolve some supernatural ability like telepathy, telekinesis or precognition. In the battle of mind over matter, the mind is at a disadvantage. Humans are the result of an evolutionary change that happened at just the right time to give us an edge and for the last 2.5 million years we’ve just been trying to make the best of what we have to work with, like all living things. Our basic anatomy places limits to how big our brains can ultimately grow and without a major change in our body plan, our brains are about as big as they can get.

The same constraints are very likely to apply to an alien creature. Why? We know that asteroids and comets are loaded with amino acids and the basic organic compounds that can give rise to new living things. When a new planet is forming, these amino acids and organics rain from the sky in the most literal way. In a habitat that has food, solvents and temperatures that wouldn’t immediately kill any living thing, there’s a very high possibility of alien life emerging from similar or even identical ingredients as the first organisms on Earth. So it’s a pretty safe bet that an alien hereditary system is going to be somewhat similar to ours and would obey the same rules of evolution as life on our planet.

This means that if on Earth, intelligence appears as a fluke, alien intelligence should appear in a similar way. Provided that an alien environment favors smarter animals (and that’s not a given), the level of intelligence in an otherworldly species would be limited by what hereditary mistake allowed for it and what these intelligent creatures could ultimately accomplish would be limited by their anatomy. One day, if we’re still around and are still able to explore space, we’ll run into creatures who have technology we’d consider to be downright magical and who’s civilizations were primeval when we were just starting out as a species. But it’s far more likely that we’ll run into feral alien animals or something very comparable to us due to the way evolution works.

[ illustration from a matte painting by Christian Hecker ]


beware the ufo thieves…

February 1, 2009

When you’re enjoying the vastness of space and the low gravity of a gas giant’s moon, keep in mind that you might not be alone. Oh and when you get out to collect a couple of samples for the scientists back on Earth, make sure your space vehicle has a good security system and its doors and windows are locked. You know, just in case…

Apparently UFOs are interested in human technology. Particularly heavy duty tires. I guess the standard issue alien anti-gravity drives aren’t all they’re cracked up to be. Somebody call Area 51 and tell them to stop the reverse engineering experiments. Bob Lazar, you’ve got one more shot at fame. Just remember, you worked with Bridgestone tires, not antimatter reactors. But in all seriousness, when we start exploring deep space and places where we might not be alone, a curious alien spacecraft passing by, could decide to take a closer look at the technology we’re using, even if they think it’s downright primitive. An alien culture might have no notion of what we call personal rights or personal property and consider anything laying around on any world to be up for grabs.

On Earth, we’ve had very similar conflicts between the first farmers and the last of the hunters and gatherers who’s territories overlapped some 12,000 years ago. The hunters would find an agricultural village and take whatever they could get their hands on because that’s what they’d ordinarily do when looking for prey. The farmers, who by now developed the concept of what’s theirs vs. what was someone else’s, would be up at arms and violently chased the hunters out of their settlements with torches, pitchforks and dogs. Likewise, on a distant planet, what these astronauts would consider theft and a major breach of good manners, aliens might consider a harmless look-see at our technology. They might even bring it back when they’re done…


Could the reason why governments around the world are covering up alien contact be a business one? An alien species able to travel between solar systems is sure to have access to a highly efficient and plentiful energy source. If this alien technology should ever fall into human hands, the rich and the powerful among us would be out of luck according to this interview with conspiracy author Jim Marrs in a Discovery Channel feature…

So let’s review. Aliens land on our planet with the technology to make cheap, plentiful energy. If the general population finds out about it, the energy industry and automakers collapse almost overnight so to protect their fortunes, the executives and their allies in the government keep all evidence of alien contact hush hush. Nothing personal, just business. But that begs two rather important questions. Would oil companies, energy conglomerates and automakers go under if people knew we had access to a new energy source? And, to quote the narrator, why wouldn’t a corporate syndicate just license whatever alien technology was available?

Just because there’s a new energy source out there, it doesn’t make the old ones obsolete right away. We can’t just plug it in and reap the benefits. Cars, central heating and power plants don’t run on excitement. Until we can upgrade our infrastructure and phase out existing technology in favor of something brand new, we would still need to rely on oil companies and automakers. Only energy companies have the kind of reach and access to capitalize on alien reactors and as the technology yields the right kind of spin-offs, automakers would be next in line to benefit.

That brings us to the second question. Why wouldn’t the rich and the powerful use their wealth to license alien technology? Some conspiracy theorists might say that it’s way too expensive to make the upgrades they’d need to plug in a new energy source into our infrastructure. And it is very expensive, But it’s not like major companies can’t raise hundreds of billions of dollars and invest in a project when they can see the payoff looming on the horizon. That’s what happened with the internet. The communication cables on the ocean floor didn’t get there by themselves. Telecom conglomerates shelled out up to $600 billion apiece to connect as much of the world as they could in order to reap the benefits of running the planet’s electronic infrastructure.

So let’s say that aliens come with a cheap, powerful energy source. What would happen? Energy companies would probably need to run it at a tiny fraction of its intended capacity to meet our demand. After all, it takes a lot more energy to travel to other solar systems than we’d need for centuries to come. Even better, all the R&D and practical testing is done. Banks would be more than willing to put together massive loan packages on what would be a very high yield, low risk deal. So if the aliens wanted to sell us their technology (and that’s a very big if), they would find no shortage of potential customers. The likes of Shell, BP and ExxonMobil would be standing in line with contracts and credit agreements in hand, waiting to sell their output to utility giants like American Electric Power.

In five to ten years the new energy source would be plugged into the energy grids and for most of the foreseeable future, energy companies using it could sit back and watch the profits come in. Should global energy demand soar, all they need is to dial up the device a couple of notches after a few gird expansions. Automakers could use virtually any portable spin-off to build new engines and churn out a new generation of cars. There would be new jobs for anyone who can understand how this technology works and how to maintain it. Alien technology would create a a major economic boom that would last for decades. Why would the people who can even think of buying alien tech and who stand the most to gain from using it, keep it under wraps?


in search of an alien eden

December 13, 2008

extrasolar worlds

Our search for life on other worlds is about heat and water. Since we only know one type of life, the creatures that inhabit our planet, we’re narrowing our focus on environments that seem to resemble our own. So far, we have a promising result. Gliese 581c and 581d are rocky worlds, much bigger than our own but with the right conditions, extremely hospitable to pretty much everything from bacteria to complex animals that could evolve to overcome the high gravity. Even intelligent life isn’t out of the question and all that is only 20 light years away. When we’ll launch the Terrestrial Planet Finder in 2015, who knows how many other promising places we might find in a hundred light year radius.

However, even if we do find that our planet is pretty common and space around us is rich with nearly perfect habitats for life as we know it, we could still be missing something important. If we want to get a true idea of how widespread life in the universe really is, we need to consider other forms of life and different kinds of organic chemistry. In fact, while we’re spending a few billion dollars on searching for life on Mars, other places in our solar system might be better destinations for an alien safari. Chemistry doesn’t stop because it gets cold. It just takes on a different form. Moons we consider icy wastes could be teeming with life by relying not on heat, but on extreme cold and if they’re included in the final tally of habitable environments, they’d change how we see the distribution of alien organisms across the cosmos.

It all has to do with solvents. Life needs three things. Organic molecules that can combine into a working mechanism, something that can be turned into energy to maintain the mechanism and let it reproduce, and a solvent to help the mechanism build the chemicals it needs. On our world, water makes the perfect solvent. It’s liquid and non-reactive. On another planet, where water would quickly be frozen as hard as steel, another non-reactive liquid could take its place. In our solar system, Saturn’s moon Titan is a perfect example of a world where living things could be using a very different solvent with the same result.

Titan is a pyromaniac’s dream. Or rather it would be if all the flammable material that the moon is made of wasn’t frozen to -290F and there was oxygen in the atmosphere. Otherwise, it’s very much like Earth. It has volcanism, oceans, lakes and an active ecosystem where all the organic materials and solvents alien bacteria would need for food and metabolic processes are being recycled and exchanged. Organisms on Titan could be using liquid ethane in exactly the same way their counterparts on Earth use water. At those super-chilled temperatures and without oxygen in the air, ethane becomes a non-reactive fluid.

So what does all this mean for our efforts to find aliens? Maybe rather than devoting all of our resources to looking for underground bacteria on Mars, we should be looking on Titan and on the more conventionally promising habitats of Jupiter’s Europa. By spreading our search across multiple worlds and by considering different organic chemistries, we stand a far better chance of finding aliens than we do by betting it all on one planet. On top of that, finding alien bacteria which use totally different chemistry from their Earthly counterparts would make it a lot easier to prove that we discovered a bona fide extraterrestrial and not just some bacterium that hitched a ride on the spacecraft sent to the habitat in question. After all, our germs have survived on another world once before.


National Geographic has taken on the final frontier, going where many documentaries have gone before but never with such style and such up to date information. It’s new special, Journey to the Edge of the Universe, is a stylish trip through as much of the known cosmos as you can squeeze into an hour and a half. If you’re into astronomy, it’s a must see. Unfortunately, this terrific show does have a few flaws that should be noted.


The first is the narration. The author is obviously in love with the subject matter and that’s something I can certainly understand. Space is beautiful and enigmatic. There’s much to appreciate about it. However, there’s quite a bit of rather distracting purple prose a good deal of which seems rather recycled and clichd. In the scope of the program, you’re a traveler who roams through the universe as a disembodied entity, witnessing all its beauty firsthand. But the esoteric musings in the background telling you how to appreciate what you’re seeing does get distracting at times.

Another point of contention is the brief mention of the Drake equation and how it supposedly predicts the possibility of millions of advanced species in the Milky Way. Actually, we can’t really solve it and we have no idea what most of the variables in the equation are in the first place. The possible solution which yields millions of alien civilizations in our galaxy is an optimistic guess at best, generously allowing for all sorts of wonderful alien habitats and with heavy Lamarckian overtones. Scientists who thought that our stellar neighborhood should be teeming with alien empires assumed that extraterrestrial life on habitable worlds should eventually develop some sort of intelligence. But intelligence is a random occurrence, not a rule.

Likewise, Journey misses something important when it highlights the world of Gliese 581c. It’s introduced as an Earth-like planet with just the right temperature for liquid water and life. The documentary also goes as far as to speculate about possible alien civilizations living in a kind of extrasolar Eden. But actually, there’s a controversy over how warm Gliese 581c really is and a number of astronomers think that its sibling, 581d is the habitable planet. Of course there’s no way to tell what the exact conditions on these planets really are.

Both of them are right on the edge of having just the right temperature for liquid water on their surface and depending on the composition of their atmospheres, both could be habitable. How about that? Two Earths in one solar system just 20 light years away. When we can travel to the stars, Gliese 581 will surely be one of our first destinations. Humans could never land on either planet though. At seven times Earth’s mass, walking on both worlds would feel like dogfighting in a supersonic jet.

Overall, Journey to the Edge of the Universe is a solid show. If you want to see some of the most talked about images and discoveries brought to life in crisp, beautiful CG, it beats almost any other space documentary by a long shot. But be ready for passionate odes to the beauty of space that go a little too far and keep in mind that some of the more tantalizing ideas about alien life aren’t nearly as definitive as they’re presented.