Assuming Star Trek‘s Borg Collective went into overdrive and decided to build a huge cube a few thousand miles wide, then yes, the exoplanet-hunting Kepler space telescope should be able to spot it. But how could Kepler distinguish a cube from a nice spherical exoplanet?
The big assumption when looking for exoplanets that drift between distant stars and the Earth — events known as “transits” — is that the only shape these detectable exoplanets come in are spheres. Obvious really.
As a world passes in front of its parent star, a circular shadow will form. However, from Earth, we’d detect a slight dimming of the star’s “light curve” during the transit, allowing astronomers to deduce the exoplanet’s orbital period and size.
The transit method has been used to confirm the presence of hundreds of exoplanets so far, and Kepler has found over 1,200 additional exoplanet candidates. But say if astronomers paid closer attention to the shape of the received light curve; spherical objects have a distinct signature, but say if something looked different in the transiting “planet’s” light curve? Well, it could mean that something non-spherical has passed in front of a star. And what does that mean? Well, that would be a pretty convincing argument for the presence of a huge planet-sized artificial structure orbiting another star. Artifical structure = super-advanced alien civilization.
Arnold tested his theory that all manner of shapes could be detected by Kepler, assuming the transiting structure was on the scale of a few thousand miles wide. In this case, Arnold was testing his hypothesis to see whether we could detect an advanced civilization’s “shadow play.” Perhaps, rather than beaming messages by radio waves, an advanced civilization might want to signal their presence — SETI style — by blocking their sun’s light with vast sheets of lightweight material. As the shape passes in front of the star, the slight dimming of starlight would reveal an artificial presence in orbit.
By putting a series of these shapes into orbit, the aliens could create a kind of interstellar Morse code.
Of course, this is a rather “out there” idea, but I find it fascinating that Kepler could detect an alien artifact orbiting a star tens or hundreds of light-years away. Although this research is only considering orbital “billboards,” I quite like the idea that Kepler might also be able to detect a large structure like… I don’t know… a big Borg mothership. Having advanced warning of the presence of an aggressive alien race sitting on our cosmic doorstep — especially ones of the variety that like to assimilate — would be pretty handy.
In 2009, I wrote about a fascinating idea: in the hunt for “Earth-like” exoplanets, perhaps we could detect the radio emissions from a distant world possessing a magnetosphere. This basically builds on the premise that planets in the solar system, including Earth, generate electromagnetic waves as space plasma interacts with their magnetospheres. In short, with the right equipment, could we “hear” the aurorae on extra-solar planets?
In the research I reviewed, the US Naval Research Laboratory scientist concluded that he believed it was possible, but the radio telescopes we have in operation aren’t sensitive enough to detect the crackle of distant aurorae. According to a new study presented at the RAS National Astronomy Meeting in Llandudno, Wales, on Monday, this feat may soon become a reality, not for “Earth-like” worlds but for “Jupiter-like” worlds.
“This is the first study to predict the radio emissions by exoplanetary systems similar to those we find at Jupiter or Saturn,” said Jonathan Nichols of the University of Leicester. “At both planets, we see radio waves associated with auroras generated by interactions with ionised gas escaping from the volcanic moons, Io and Enceladus. Our study shows that we could detect emissions from radio auroras from Jupiter-like systems orbiting at distances as far out as Pluto.”
Rather than looking for the magnetospheres of Earth-like worlds — thereby finding exoplanets that have a protective magnetosphere that could nurture alien life — Nichols is focusing on larger, Jupiter-like worlds that orbit their host stars from a distance. This is basically another tool in the exoplanet-hunters’ toolbox.
Over 500 exoplanets have been confirmed to exist around other stars, and another 1,200 plus exoplanetary candidates have been cataloged by the Kepler Space Telescope. The majority of the confirmed exoplanets were spotted using the “transit method” (when the exoplanet passes in front of its host star, thereby dimming its light for astronomers to detect) and the “wobble method” (when the exoplanet gravitationally tugs on its parent star, creating a very slight shift in the star’s position for astronomers to detect), but only exoplanets with short orbital periods have been spotted so far.
The more distant the exoplanet from its host star, the longer its orbital period. To get a positive detection, it’s easy to spot an exoplanet with an orbital period of days, weeks, months, or a couple of years, but what of the exoplanets with orbits similar to Jupiter (12 years), Saturn (30 years) or even Pluto (248 years!)? If we are looking for exoplanets with extreme orbits like Pluto’s, it would be several generations-worth of observations before we’d even get a hint that a world lives there.
“Jupiter and Saturn take 12 and 30 years respectively to orbit the Sun, so you would have to be incredibly lucky or look for a very long time to spot them by a transit or a wobble,” said Nichols.
By assessing how the radio emissions for a Jupiter-like exoplanet respond to its rotation rate, the quantity of material falling into the gas giant from an orbiting moon (akin Enceladus’ plumes of water ice and dust being channeled onto the gas giant) and the exoplanet’s orbital distance, Nichols has been able to identify the characteristics of a possible target star. The hypothetical, “aurora-active” exoplanet would be located between 1 to 50 AU from an ultraviolet-bright star and it would need to have a fast spin for the resulting magnetospheric activity to be detectable at a distance of 150 light-years from Earth.
As we’re talking about exoplanets, magnetospheres and listening for radio signals, let’s throw in some alien-hunting for good measure: “In our Solar System, we have a stable system with outer gas giants and inner terrestrial planets, like Earth, where life has been able to evolve. Being able to detect Jupiter-like planets may help us find planetary systems like our own, with other planets that are capable of supporting life,” Nichols added.
Although Nichols isn’t talking about directly detecting habitable alien worlds (just that the detection of Jupiter-like exoplanets could reveal Solar System-like star systems), I think back to the 2009 research that discusses the direct detection of habitable worlds using this method: Aliens, if you’re out there, you can be as quiet as you like (to avoid predators), but the screaming radio emissions from your habitable planet’s magnetosphere will give away your location…
This rather outlandish, sci-fi notion comes straight from the fertile minds of researchers from MIT, the Massachusetts General Hospital and Harvard University who are proposing a biology experiment that could be sent on a future Mars surface mission. If their hypothesis is proven, we wouldn’t only have an answer for the age old question: Are we alone? but we’d also have an answer for the not-so-age-old question: Did life from Mars spawn life on Earth?
The idea goes like this: countless tons of material from Mars has landed on Earth. We know this to be true; meteorites have been discovered on Earth that originate from the Red Planet. These rocks were blasted from the Martian surface after eons of asteroid impacts, and the rocks then drifted to Earth.
If there was once life on Mars — a concept that isn’t that far-fetched, considering Mars used to boast liquid water in abundance on its surface — then perhaps some tiny organisms (not dislike the hardy cyanobacteria that is thought to have been one of the earliest forms of life to evolve on our planet) hitched a ride on these rocks. If some of these organisms survived the harsh conditions during transit from Mars to Earth and made it though the searing heat as the meteorite fell through our atmosphere, then perhaps (perhaps!) that is what sparked life on Earth.
You may have heard a few variations of this mechanism, it is of course the “panspermia” hypothesis. Panspermia assumes that life isn’t exclusive to just one rocky body like Earth, perhaps life has the ability to hop from one planet to the next, helped on its way by asteroid impacts. Not only that, but perhaps (perhaps!) tiny microorganisms could drift, encased in interstellar dust, akin to pollen drifting in the wind, seeding distant star systems.
Naturally, when considering the distance between the planets (let alone the light-years between the stars!), one might be a little skeptical of panspermia. But it certainly would help us understand how life first appeared on Earth. After all, it’s not as if the solar system has a natural quarantine system in place — if Mars had (or has) bacteria on its surface, perhaps they have been spread to Earth, like an interplanetary flu bug. Also, as experiments are showing us, microorganisms have an uncanny ability to survive in space for extended periods of time.
So, according to my esteemed Discovery News colleague Ray Villard, the MIT team led by Christopher Carr and Maria Zuber and Gary Ruvkun, a molecular biologist at the Massachusetts General Hospital and Harvard University, are proposing to build an instrument to send to Mars. But this instrument won’t be looking for signs of life, it will be testing the hypothetical Martian DNA and RNA. Should this interplanetary paternity test prove positive, proving a relationship between Earth Brand™ Life and Mars Brand™ Life, then this could be proof of some extraterrestrial cross-pollination.
Although this is complete conjecture at this time, as there is no proof that life has ever existed on Mars (despite what research in dodgy research journals tell us), it is certainly an interesting idea that would not only test the hypothesis of panspermia, but also give us a clue about the potential human colonization of Mars.
This could give us pause about sending humans to a germ-laden alien world. It would be an ironic twist on the H.G. Wells classic 1898 novel “The War of the Worlds,” where invading Martians succumb to the common cold from Earth microbes.
See, Wells’ Martian warriors should have done genome testing first.
Original post: On Saturday, a NASA astrobiologist announced his “irrefutable proof” that aliens — the size of bacteria — exist. Using a sophisticated electron microscope, Richard Hoover looked deep into meteorite samples to see complex fossilized microscopic structures that looked suspiciously like bacteria found here on Earth.
Some of the suspect alien microorganisms even resemble cyanobacteria, a basic microorganism that helped make early-Earth hospitable to life by producing oxygen. Cyanobacteria can live in space for extended periods of time; tests on the International Space Station have shown the single-celled specks are hardy little buggers, surviving in a kind of “suspended animation,” sleeping for months (even years) in vacuous, frozen, high-radiation conditions. When brought back to Earth, the critters come back to life.
Needless to say, when Hoover announced this discovery of “alien” microbes, I wasn’t the only one who was thinking panspermia, the hypothetical mechanism where life — in the form of a microbe like cyanobacteria — hops from one planet to the next encased inside meteoroids.
Is this really proof of aliens? Is it evidence for panspermia? Does this mean life on Earth may have been seeded by alien microbes stowing away inside chunks of space rock? Does mankind need to invent an anti(alien)bacterial handwash?! (I’ve watched The Andromeda Strain.)
As mentioned in my Discovery News article on the subject, I’m skeptical about Hoover’s claims. This isn’t because I think Hoover’s work is rubbish (I have yet to finish digesting his lengthy paper), it’s just the way he decided to publish his work. The online Journal of Cosmology isn’t exactly the best place to submit your paper if you want your research to be taken seriously. And why the hell he gave FOX News the “exclusive,” I have no idea.
Sure, Hoover has discovered some odd-looking, alien-looking, bacteria-sized shapes in meteorite samples (he’s even done some interesting chemical analysis on the micro-“fossils”), but he’s going to have to do a far better job at convincing the scientific community that they are extraterrestrials.
Personally, I think these dinky “fossils” are a little too well preserved. Perhaps a far simpler explanation can be found? *cough* Contamination. *cough*
I’d love to know what NASA’s official line is, they seem to be staying remarkably quiet considering one of their employees has just announced the discovery of ET…
“Panspermia” is a hypothesis that life is transferred from planet-to-planet and star system-to-star system through some interplanetary or interstellar means.
But for panspermia to work, this life needs to be sufficiently protected — and, um, kept alive — from the worst the universe can throw at it (such as radiation, cold and vacuum). Alas, when considering interstellar hops, the timescales are likely too long (i.e. millions of years) and said life will be dead on arrival.
We know that Earth Brand™ life is a pretty hardy thing. After all, we’ve tortured terrestrial microbes and mosquito larvae in the vacuum of space to see if they’d pop. Sure enough, when brought back to terra firma the various creatures wriggled and squirmed as if nothing had happened. But these experiments in orbit were carried out over the course of months or years. While this might be suitable for interplanetary transfers, it would take millions of years for an extraterrestrial interloper to traverse even a modest interstellar gap.
Any hitchhikers that were alive on a stellar wind-blown particle will be toast (or, more accurately: freeze-dried, pulverized, mashed-up, DNA-shredded mess) on reaching their exotic destination eons later.
What good are tiny alien fossils when the panspermia model is supposed to seed other worlds with life… that’s actually alive?
Enter a new incarnation of pansermia: “Necropanspermia.”
Conceived by Paul Wesson, of Herzberg Institute of Astrophysics in Canada, necropanspermia is the transfer of the information of life to new worlds, wriggling extraterrestrial bacterium not required.
Assuming alien microbial life has made the trip across interstellar space, died and then fossilized, Wesson reckons the information contained within the long-dead microbe could be used as some kind of template by a hospitable world to use and grow new life. (It’s not quite zombie science, but it’s hard not to say “reanimated alien corpse.”)
Wesson even goes so far to suggest ET’s microbial remains can be “resurrected.”
“Resurrection may, however, be possible.” Wesson concludes in his Space Science Reviews paper. “Certain micro-organisms possess remarkably effective enzyme systems that can repair a multitude of strand breaks.”
Hypothesizing about various forms of panspermia may seem more like a philosophical argument, but Wesson suggests that we might be able to find evidence for necropanspermia if we collect some dust samples from the outermost reaches of the solar system, far enough away from Earth’s biological pollution.
The Voyager 2 spacecraft has been speeding through the Solar System since 1977 and it’s seen a lot. Besides scooting past Jupiter, Saturn, Uranus and Neptune, the probe is now passing through the very limit of the heliosphere (called the heliopause) where it has begun to detect a magnetic field beyond the Solar System. The fact we have man-made objects exiting our star system is something that makes me goosebumpily.
For some perspective, Voyager 2 is so far away from Earth that it takes nearly 13 hours for commands sent from Earth to reach the probe.
After decades of travel, the NASA spacecraft continues to relay data back to us, making it one of the most profound and exciting space missions ever launched. Perhaps unsurprisingly, the aging explorer recently experienced a glitch and the data received by NASA was rather garbled.
Naturally, the conspiracy theorists were out in force quickly pointing their sticky fingers at a possible encounter of the 3rd kind. How these ‘aliens’ found the probe in the first place and reprogrammed the transmission for it to appear corrupt Earth-side is beyond me, but according to an ‘expert’ in Germany, aliens (with an aptitude for reprogramming 30 year old Earth hardware, presumably) were obviously to blame.
One of the alien implication articles came from yet another classic ‘science’ post thrown together by the UK’s Telegraph where they decided to take the word of a UFO expert (obviously a viable source) without any kind of counter-argument from a real expert of real science. (But this is the same publication that brought us other classics such as the skull on Mars and the Doomsday Turkey, so it’s not too surprising.)
As I discussed in a recent CRI English radio debate with Beyond Beijing hosts Chris Gelken and Xu Qinduo, the Voyager-alien implication is beyond funny; an entertaining sideline to poke fun at while NASA worked out what actually went wrong. But the big difference was that Chris and Xu had invited Seth Shostak (from the SETI Institute) and Douglas C. Lin (from the Kavli Institute for Astronomy and Astrophysics at Peking University) to join the fun. No UFO expert in sight, so the discussion was biased toward science and logic, not crazy talk.
This glitch was thought to occur in the flight data system, which formats information for transmission to Earth. Should something go wonky in its memory allocation, the stuff it transmits can be turned into gibberish.
Although it isn’t known how this single bit was flipped (and we may never know, as Voyager 2 is an awful long way from home), it sounds very much like a cosmic ray event interfering with the onboard electronics. As cosmic rays are highly energetic charged particles, they can penetrate deep into computer systems, causing an error in calculations.
And this situation isn’t without precedent either. Recently, NASA’s Mars Reconnaissance Orbiter (MRO) was hit by a cosmic ray event, causing the onboard computer to switch to “safe mode.” Also, Voyager 2 is beginning to exit the Sun’s outermost sphere of influence, where turbulence and confused magnetic fields rule. If I had to guess, I’d say — statistically-speaking — the probe might have a greater chance of being hit by the most energetic cosmic rays from deep space.
Just because something “mysterious” happens in space doesn’t mean aliens, the Illuminati or some half-baked doomsday phenomenon caused it. Before jumping to conclusions it would be nice if certain newspapers and UFO experts alike could look at the most likely explanation before pulling the alien card.
Alas, I suspect that some things will never change.
I managed to watch District 9 last night, and it was awesome. I may as well tell you my conclusion up-front, just in case you don’t want to read on, because I’m not going to be able to avoid mentioning some spoilers. So, if you haven’t already done so, get down the theatre now to watch a unique and enthralling sci-fi docu-action-thriller (but beware, there’s lots of exploding heads and alien gore, so go easy on the popcorn and fizzy drinks).
Generally, it looks like District 9 has received good reviews and a robust nod from the science fiction community, and now I’m going to weigh in with a review from Astroengine.com.
First and foremost, I think D9 surpassed pretty much all of my expectations, which is rare for Hollywood produce these days. It was little surprise then, that this movie wasn’t of the Hollywood brand, it came from the genius mind of the South Africa-born director Neill Blomkamp and Peter Jackson‘s production company Wingnut Films. The whole thing was shot in the gritty South African city of Johannesburg.
Setting the scene
An alien spaceship breaks down on Earth and comes to a stop over Johannesburg. After several weeks of not seeing any sign of life, the authorities decide to cut their way into the ship. They find hundreds of thousands of malnourished insect-like, human-sized aliens inside. Humans do the right thing by setting up a makeshift shelter in Johannesburg, called District 9 (it is of no coincidence that there’s a similarity with the real events in District Six during the 1966 apartheid government rule). So far, so good.
After a couple of decades of living in the D9 shanty town, the local human populous is getting fed up with their alien neighbours (they derogatively call “prawns”). As it turns out, these aliens don’t appear to be very smart and they are certainly not organized. They have no leader and they are thought to be the “workers” of their alien race. They are far from being the sophisticated invasion party one would expect a technologically advanced race to be like.
This is the coolest thing about this movie; the aliens are cast as the unfortunate underdogs that are being forced to stay on Earth by their human captors. Why? Technology, of course.
A military organization called Multinational United (MNU) is put in charge of moving the million-plus alien beings to a new concentration camp housing facility 200 miles away. The whole operation is led by a bumbling MNU field operative called Wikus van der Merwe (played by Sharlto Copley). Wikus is your standard trying-way-too-hard-to-please-and-failing guy with a loving wife (who can somehow see past his many social flaws) and tough father-in-law (who is the head of MNU and responsible for giving Wikus this “big break”). Wikus is almost like a South African hybrid of Steve Carrel, Steve Coogan and Simon Pegg.
There are some fantastic moments when an overly confident Wikus knocks on doors serving eviction notices to the aliens. It is an awkward, yet captivating scenario. The MNU, an organization that obviously has absolute power over the situation, has decided to make the eviction of the aliens seem “legal” by getting them to sign (or “scrawl”) their signature on a small piece of paper. Naturally, the aliens aren’t too happy about all this and Wikus is met with a variety of responses (one where the alien slaps the paper out of his hand and storms off — Wikus triumphantly points out that a tentacle hit the paper, it is therefore signed). Another funny legality is that the aliens have been given human names (such as “Christopher Johnson”) to make their very existence bona fide.
In the first third of the film there are several reminders that the MNU isn’t a tolerant organization. If the armed units are faced with any resistance, they kill on-site. However, they are faced with an impoverished, desparate alien populous that will do anything for a tin of cat food. They are more concerned about chewing on car tires than being shot at. The cat food actually becomes a commodity in District 9, a currency the local Nigerian gangs use to trade for weapons. There is also a hilarious reference to “inter-species prostitution.”
The movie starts off in hand-held documentary style (not in an annoying Blair Witch Project way), following Wikus on his alien eviction adventures, but the atmosphere of the story changes after he accidentally sprays himself in the face with a black fluid in an unidentified cylinder. There is then an altercation with one of “Christopher Johnson’s” friends who tries to distract attention away from the shack that contained Wikus was sprayed in.
Cue alien death, execution style, by the bald-headed bad-ass special unit military guy.
A dodgy stomach and a broken arm later, Wikus is stuck in a situation he can’t get out of. You remember that spray? It turns out that it’s not only a special, highly refined spaceship fuel, it’s also a way to really mess up your day if you breathe it in. Wikus has started to change into an alien.
This is probably one of the weaker parts of the story. How a nasal spray is going to tinker with your genetics in such a way that will turn you into a human-alien hybrid, I don’t know, but District 9 didn’t start with a claim that it was going to be totally scientifically accurate. Somehow Wikus’ left hand also turns into a clawed alien appendage. I’ll turn a blind eye to the fudged human-alien biology lesson.
So we’re locked in a race against time as MNU agents track down and capture Wikus as Wikus becomes more and more prawn-like. From being a flawed MNU officer, he has now become the most valuable human on the planet; he is the only one capable of operating the alien technology (their weapons only react to alien biology).
During the period when Wikus has been captured and is being experimented on, the MNU shows itself for what it really is; a weapon research facility with little regard for human life, let alone alien life. In one particularly tough scene, Wikus has to fire an assortment of alien weaponry at animal carcasses against his will…
[If you told me before watching District 9 that I would feel shocked by the death of a CGI’d alien being, I’d assume I would have been drinking heavily beforehand. But no, I hadn’t had a beer (although the Pepsi was quite syrupy).]
…At this point, a live alien is dragged out with an X painted on its torso. When stood, shivering at the end of the shooting range, Wikus is ordered to shoot the alien. He refuses, crying. You see that Wikus does have a certain degree of respect for the aliens and he is certainly adverse to killing them. Unfortunately, tied in place, and alien weapon pushed in this hand, he’s forced to fire the gun at the frightened “prawn,” who explodes in a bloody mess.
It’s pretty grizzly and also a little upsetting. I think this is the moment in the movie that you know you are dealing with a different kind of sci-fi storyline and Blomkamp does an amazing job to shock, but not to go over the top.
Agony and terror
Also, you realize Sharlto Copley’s acting ability is nothing short of outstanding. Before the weapon testing scene, there’s a fair amount of humour angled at his character, afterwards you can feel his agony and terror.
Needless to say, Wikus escapes and runs to the only place he can find refuge: District 9. Fortunately, we are allowed a little time to recuperate after the MNU experiments as Wikus turns into a convict running through his own city.
After a period of making friends with the smart “Christopher Johnson” and little (and quite cute) pint-sized alien son, Wikus and “Christopher” work out they need each other to find a solution to the problems they are facing. “Christopher” needs to retrieve the mysterious cylinder from the MNU HQ to make the command ship (hidden under District 9) function, and Wikus needs alien technology from the mothership hovering overhead to stop him from going 100% prawn.
And so begins an orgy of human-popping. In the best human-alien buddy pairing since Han Solo and Chewbacca, Wikus and “Christopher” assault the MNU HQ with the best alien guns Wikus could steal from those Nigerian “inter-species prostitution” gangs (with a fetish for drinking alien blood and collecting alien junk they can’t use). Of course, now that Wikus can operate these guns, he can have some fun.
A clip from District 9: Wikus uses an alien weapon for the first time (language NSFW):
Many reviews of District 9 are critical of the amount of action in the rest of the film, but I thought it was pretty cool. Science-lite, but it sure was a tour de force of movie action imagination. My particular favourite was Wikus’ energy-lightning-bolt gun that had no difficulty in snuffing out MNU personnel in a cloud of blood vapour.
A few gun battles later, and we return to District 9, plus fuel cylinder. Quite a lot happens, but to cut a long story short… there were a lot of explosions. I don’t want to give away the ending, but it was fairly routine, with a couple of minor plot twists. When I say routine, I don’t mean it was boring, the movie simply went its course without too many surprises. Well, there might have been one or two…
Occasionally, out of the CGI’d dust of orgasmic fight sequences of Transformers 2 and the predicted lack of plot in the forthcoming 2012, the movie industry churns up a gem of a sci-fi flick.
I suspect Moon is one of those rare movies (I am still trying to find time to get my bum down the cinema to watch it) that combines plot, effects and scientific accuracy (just about) to arrive at a genuinely good film.
And then there’s District 9, due for release in August. At first look of the trailer, you’ll see why I’m getting a little excited:
I was expecting the same old aliens invade, world on fire, Will Smith punches alien, USA saves the world storyline at first, but if you read the IMDB plot summary (spoilers!), you’ll be pleasantly surprised.
Damn, I have to share the plot… stop reading now if you want to be totally vague about the story of District 9.
Basically, rather than invading Earth, these alien dudes have landed on our planet seeking refuge after their home world died. Their spaceship arrives over South Africa and thirty years later, these once-advanced alien beings have been turned into social outcasts, restricted to an alien slum called District 9. People have lost patience with looking after these creatures, but agencies hold onto these aliens against their will to learn about their technologies. Then, it would appear the aliens start to fight back…
It’s set in a gritty Johannesburg location, the CGI looks subtle, plus Peter Jackson (Lord of the Rings director, say no more) is involved, so there’s some hope this might be a unique and thrilling sci-fi. I get the feeling there is a lot of play on alien rights, the welfare of ET integrated in society (or not), with a healthy dose of alien-racism (alienation?) thrown in.
Us humans will be the bad guys! Awesome! Filthy aliens…
On reading an article in The Daily Galaxy today, I was interested by what the author had to say. In a nutshell, the article pointed out that it is a big mistake to believe we are the only intelligent life in the Milky Way.
Why is that?
The only reason given was that there are billions of stars, it is therefore foolish to think we are the only example of an advanced species. Unfortunately, there is no evidence to suggest that we aren’t the only intelligent life form in our galaxy. Just because there are hundreds of billions of stars possibly with billions of habitable planets does not constitute evidence that we’re not alone. That’s what science is all about, formulating a theory and then gathering the evidence. Simply saying, “There’s lots of stars, therefore there must be an intelligent species out there,” doesn’t cut it.
Dr Frank Drake toiled with this idea to eventually arrive at the famous Drake Equation, a concept I have never felt at ease with:
How can you arrive at the conclusion that we are not the only intelligent life in the galaxy simply because there are a lot of stars?
It is true that the Milky Way contains billions of stars, of which a high percentage probably have exoplanets not dissimilar to Earth orbiting them. There’s every chance that a smaller percentage of those Earth-like terrestrial exoplanets have some kind of basic life form slivering around (or indeed swimming, flying, walking or ‘talking’). Also, there’s the chance that some of these exoplanets have nurtured something that we’d consider to be ‘intelligent.’
Now this is where things start to get a bit tricky.
There are massive international efforts under way to find any kind of extraterrestrial life. We’re toasting soil samples on Mars in the hope of finding the biological signature, and we’re using full-blown antennae scouring the skies for any organized signal from an intelligent alien species. However, whether we are looking for microbial life in the Solar System or something a little more sophisticated beyond, our search for extraterrestrial life is based on only one model: Earth.
It’s all very well saying that we should be looking for other possible forms of life, but if we have no experience of it, how do we know what to look for?
It’s a similar question to, “What is beyond a black hole’s event horizon?” We have no idea, because we cannot experience it, the physics of our Universe simply do not apply beyond an event horizon.
There are a lot of ideas, theories and conjecture but at the end of the day, we have to assume ET will have some trait we are familiar with.
When looking for intelligent extraterrestrials we make the assumption that these civilizations have progressed in a similar way to us, eventually transmitting radio signals (perhaps even laser beacons) to communicate on their home world, between planets with their own kind, or even reaching out into the cosmos, signalling their presence to other life forms capable of receiving interstellar signals.
We’ve been leaking radio signals into space for the last century and we are constantly communicating with our planetary probes. There’s every chance that if there’s an intelligent alien (with a radio receiver) within 100 light years, we may have already been detected. We are also being a bit more proactive these days, using programs such as Messaging Extraterrestrial Intelligence (METI) to make our presence known. (But what should we be saying?)
SETI, METI, SETA… SETT?
Unfortunately, apart from one isolated case, the Search for Extraterrestrial Intelligence (SETI) has drawn up blanks, we don’t think we’ve heard anything in the cosmos that’s originated from an alien.
The Milky Way is very old, in fact, the oldest star in our galaxy has been burning for 13.2 billion years (compare that with the age of the Universe at 13.74 billion years); you’d logically think that something resembling an intelligent civilization would have popped into existence in that time. If they did, surely we’d have detected them by now, wouldn’t we?
Actually, this spawns yet another debate: Have ancient interstellar alien civilizations come and gone? Was there a frenzy of intelligent life popping up all over the galaxy in the billions of years that our Sun was a proto-star surrounded by a proto-planetary disk? If old alien intelligence has since become extinct, our few thousand years as an evolving civilization is a mere spark in universal time scales. Could it be that we’ll have to wait until we can actually visit interstellar destinations first-hand to do the SETI equivalent of an archaeological dig, looking for alien artefacts? Perhaps SETI should be changed to the Search for Extraterrestrial Artefacts (SETA), where we’d have to look for evidence of alien civilizations past.
There’s another factor to consider. What if an advanced extraterrestrial civilization simply isn’t transmitting? If this is the case, perhaps we should consider a Search for Extraterrestrial Technology (SETT). In this case we could look for alien megastructures, searching for the stuff of science fiction. These structures could include examples of Dyson Spheres, huge alien-made hollow spheres containing a star; a means to harvest all the stellar energy for a vastly advanced civilization.
These are all options, and we shouldn’t close any possibility, no matter how extreme they may be.
There’s a reason why we haven’t received a signal via SETI, but we have no idea about what it could be. We really could be alone in the Milky Way. But then again, there’s a huge number of reasons why we might not be receiving a message from an intelligent species.
SETI may not be an interstellar switchboard, but the reasons for this are far from obvious. The theory that we are alone is just as valid as the theory that we are actually a part of a vast interstellar ecosystem. Until we have scientific evidence, we can’t say either way.
I’m quickly realising that the Super Bowl ad break is as eagerly awaited as the match itself. I’ve lived in the US for 3 Super Bowls, and each time there’s the buzz, “I wonder what the[insert company here]ad will be this year?” It’s funny, I’ve only watched one Super Bowl (in my first year) and I was astonished that there were more ad breaks than (American) football. (Which is no bad thing, I’m not a huge fan of the sport, give me football–soccer–any day.)