Fewer Than 10 ET Civilizations In Our Galaxy? 642
Al writes "The Fermi Paradox focuses on the existence of advanced civilizations elsewhere in the galaxy. If these civilizations are out there — and many analyses suggest the galaxy should be teeming with life — why haven't we seen them? Carlos Cotta and Álvaro Morales from the University of Malaga in Spain investigate another angle by considering the speed at which a sufficiently advanced civilization could colonize the galaxy. Various analyses suggest that using spacecraft that travel at a tenth of the speed of light, the colonization wavefront could take some 50 million years to sweep the galaxy. Others have calculated that it may be closer to 13 billion years, which may explain ET's absence. Cotta and Morales study how automated probes sent ahead of the colonization could explore the galaxy. If these probes left evidence of a visit that lasts for 100 million years, then there can be no more than about 10 civilizations out there."
Too Many Free Variables (Score:5, Funny)
Fewer Than 10 ET Civilizations In Our Galaxy?
All this is assuming that we would know immediately if there were a 50-100 million year old alien probe in our solar system's backyard. Stack that on top of all the non-empirical data based percentages that go into the Fermi paradox and ...
*puts on Twilight Zone music*
Human beings are the alien probe!
And man, we had better start compiling that report that's due when Quetzalcoatl/Jesus/Osiris/Thoth/Viracocha get back here. He's gonna be pissed when he sees that we just threw a huge party and trashed the place instead of assessing the resources!
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Yes. There could be half a bajillion alien probes in the Kuiper belt, transmitting the latest antics of the Earthlings right to GalaxyTV, and we'd have no idea.
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I at least hope they're getting a good laugh.
Re:Too Many Free Variables (Score:4, Insightful)
"I at least hope they're getting a good laugh."
Or weeping for what we are doing to ourselves and Earth.
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"Space, is big. Really big. You just won't believe how vastly hugely mindboggingly big it is. I mean you may think it's a long way down the road to the chemist, but that's just peanuts to space.
-Hitch-hiker's Guide to the Galaxy
Re:Too Many Free Variables (Score:4, Funny)
Why doesn't Ross, the bigger of the 'Friends', simply just EAT the other two?! - Omicron Persei 8
Re:Too Many Free Variables (Score:5, Funny)
Re:Too Many Free Variables (Score:5, Funny)
Re:Too Many Free Variables (Score:5, Funny)
Re:Too Many Free Variables (Score:5, Interesting)
Re:Too Many Free Variables (Score:5, Interesting)
All this is assuming that we would know immediately if there were a 50-100 million year old alien probe in our solar system's backyard.
Yes. There could be half a bajillion alien probes in the Kuiper belt, transmitting the latest antics of the Earthlings right to GalaxyTV, and we'd have no idea.
I disagree. I shall propose what will be known as The eldavojohn Paradox which states that: If extraterrestrial life were watching our TV, surely Fox and the WB would have been attacked by now ... or at least a very harshly worded intergalactic message would have been delivered to the Fox executives about their nonsensical canceling of shows like Firefly and Futurama while promoting unadulterated drivel.
... we'll just come back later when you're not busy, ok?"
You see, my assertion that extraterrestrials would enjoy the same television as I is just as utterly inept as assuming that their primary goal is establishing contact with other extraterrestrials. Who knows? Maybe they're too busy jumping between parallel universes to waste time talking to the Corky from Life Goes On of the Milky Way Galaxy? (that being us)
Maybe they showed up and watched World War I and II and said, "Wow, that is some heavy shit. We'll
Isn't the Maybe Game fun? It's like I'm a sci-fi writer with me as my own audience.
Re:Too Many Free Variables (Score:5, Insightful)
If there exists another race like earth-based humans, it proves our evolution is completely random because no intelligent, higher being would make us on purpose twice. On the other hand, if we are here our of sheer randomness then it is most probable we are, in fact, alone.
Re:Too Many Free Variables (Score:4, Interesting)
I often wonder if we are Earth's end-of-the-line inhabitant. Animals evolve to adapt to their environments. Us humans adapt the environment to suit us. Have we stopped evolving? It's a dangerous situation if we have, because then we become a non-changing environment for all the creepy-crawlies we are host to. Bacteria will rule the world in 100 million years!
Re:Too Many Free Variables (Score:4, Interesting)
I meant random in the sense that a higher being wasn't planning our existence.
Evolution is so slow I doubt we have the patience or longevity to observe it. In addition to "changing out environment to suit us," we also seek to prevent change from happening to our environment. I'm sure there are millions of people out there who would go to great lengths to ensure the survival of all extant species. Ironically, their logic is that man is changing things and endangering those species, yet not allowing them to become extinct is at odds with our changes. Of course, they'll argue that our changes are not natural, which is impossible. We occurred naturally, therefore whatever we do is part of nature, for better or worse.
Perhaps we have reached a dead end for physical evolution, and given no other changes we'll outgrow this planet long before we figure out how and where to move off of it. But I suspect social evolution will intervene before that happens. Logan's Run, Soylent Green, 1984, Brave New World...Pick your future.
In closing, I leave you with the words of the great prophets Fishbone: "Give a monkey a brain and he'll swear he's the center of the universe."
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Maybe Firefly was too close to the truth...
"[Shut down Firefly or we wipe out the planet.]"
"[What? It's a good show, and the ratings are...]"
"[NOW!]"
Joss Whedon doomed us all with Serenity.
Re:Too Many Free Variables (Score:5, Funny)
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I have the same feelings about astronomers.
Re:Too Many Free Variables (Score:5, Insightful)
Re:Too Many Free Variables (Score:5, Funny)
Cheers!
Re:Too Many Free Variables (Score:5, Funny)
Human beings are the alien probe!
Oh no! I don't want to be shoved up anything's ass!
Re:Too Many Free Variables (Score:5, Funny)
Commander Xygzymmr,
Probe designate r_jensen11 appears to be defective. We should pick him up on our next maintenance run for reprogramming. Recommend Regimen 7: "Probe 'em till he'd rather be the probe".
- Engineer Morpsyx
What if... (Score:3, Interesting)
Sumary of the article: we pull numbers out of thin air and imagine stuff in consequence. I did a lot of that kind of "what if" as a kid with friends.
Give it time... (Score:5, Informative)
A good summary. Especially since they assume because we sent out a "identifier" once, that it is logical that all other civ's would continuously do that, just in case things change, and some youngsters show up. Instead of 1) send probes, get the info you want (or trash your orbit with satellites and crap so you can't lunch anything else) and give up, staying in your own solar system.
Not to mention we only see stuff at the speed of light, if they only send stuff at 1/10 the speed of light. Anyone over a thousand light years away hasn't even seen any signs of life in our galaxy yet, let alone had a chance to respond in a manner that we will then be able to see for a few thousand more light years.
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Fear (Score:2)
Cotta and Morales study how automated probes sent ahead of the colonization could explore the galaxy. If these probes left evidence of a visit that lasts for 100 million years, then there can be no more than about 10 civilizations out there
Maybe there are more, but the rest are afraid of running into an advanced civilization who'll treat them as cattle
Why (Score:3, Interesting)
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I wonder why should one consider a colonisation of the whole Galaxy?
Because someone else might have the same idea, and you need to beat them to it.
Isn't it a too damn big territory to defend - explore - colonize?
Well, if you manage to colonize the whole galaxy, you probably don't have to worry about defending it from external threats for quite a while.
Without talking about the astronomical (ha ha) amount of human (E.T.) resources it would take to launch such an enterprise!
Yes, it takes quite a bit of re
Re:Why (Score:5, Insightful)
"Well, if you manage to colonize the whole galaxy, you probably don't have to worry about defending it from external threats for quite a while."
Okay, that's the funniest thing I've ever heard.
Q: What's the biggest threat humanity has ever faced?
A: Itself.
Creating thousands of splinter civilizations with no emotional investment in the species homeworld is a recipe for galactic war if I've ever heard one.
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Creating thousands of splinter civilizations with no emotional investment in the species homeworld is a recipe for galactic war if I've ever heard one.
What would be the point?
Consider two "rival" worlds separated by a modest distance of 50 light years. Now assume that the top speed that ships can go remains 1/10 light speed as mentioned in the article. That's 500 years for your fleet to get to the other world. The time dilation at that speed would be small enough to be insignificant. Multi-generational warships anyone?
So let's instead consider that we push the speed envelope. We're still limited in how fast we could go. Say we push it to 80% or maybe 90%
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You need to throw in a bunch of hand waving about statistics.
It is at least possible that we are the first, most advanced civilization, out of some huge number in this vicinity (even if it is extremely unlikely...).
Mind the gap! (Score:5, Insightful)
bjourne points out: "They assume that alien civilizations would grow exponentially like humanity. To maintain exponential growth the civilization would inevitably have to colonize other planets, other solar systems and even other galaxies."
What they really assume is that the laws of physics apply broadly across the cosmos. Darwin and Malthus do the rest.
The real question is how hard it is to jump the gap from one world to the next. Science fiction authors assume this is not only possible but relatively easy, because otherwise they would have no story to write. Travel (of the few) within the solar system seems plausible. Travel (of the many) to neighboring stars is far beyond daunting.
Consider Malthusian growth: Our population today is 6.602 billion souls. The current growth rate is 1.167% per annum. (Numbers are a couple of years old - it doesn't change the result.) Do the math.
Today there were 210,000 more souls and 6000 tons more human flesh pressing inward on Mother Earth than yesterday. Tomorrow there will be 210,000 more. The day after - another 210,000. In six months that will be 211,000 per day - in a year, 212,000 per day, and so forth and so on. Less than a year from now there will be another 1.8 million tons of human flesh literally shouldering other species into extinction. That's not 1.8 million tons total - that's just the additional growth of skin and hair and sinew and good red meat locked up in your mama's Soylent Green recipe.
For space travel to matter in the solution of this problem, we have to build a fleet of ships capable of offloading 210,000 people - a new space fleet every day, year after year - forever. A space shuttle carries a crew of seven - so we need 30,000 space shuttles a day. (Of course, that only gets you to low Earth orbit.) Each year we would have to move at least that 1.8 million tons of human cold cuts - that's the equivalent of 18 Nimitz class aircraft carriers - to some other distant, unwelcoming world.
And then, of course, you've just shifted the horizon of the always looming catastrophe to a collection of planets rather than a single planet. Since this is a doubling issue, colonizing another planet - say, a terraformed Venus - just buys you an additional 60 years.
Re:Mind the gap! (Score:5, Interesting)
No we don't.
We need robots, breeding tanks, freeze-dried embryos. Put a few thousand of 'em (along with DNA samples of a few thousand other humans) on a spaceship, and let the ship take care of the rest.
The goal isn't to offload Earth's population at some linear rate.
The goal is to spawn self-replicating colonies. If the ship travels at 10% of the speed of light (500 years to find a habitable planet within 50 light-years), but the ship can be made cheaply enough (suppose by the year 2200 we can do it for the GDP equivalent of an aircraft carrier and its support fleet), you just fire off a ship in a random direction every 10 years.
The ship finds a suitable world, sets up shop, and the colonists spend the next 1500 years bootstrapping themselves from a Serenity-like Wild West settlements into million-person planetary civilizations capable of building their own seedships. Lather, rinse, repeat.
Some colonies fail. Big deal. Sometimes you'll spread at 0.01c (500 years travel time, 4500 years of playing Sid Meier's Alpha Centauri). Sometimes you'll get lucky - (A ship that lasts for 4500 years and travels 450 light-years - and the lucky colonists reboot after only 1000 turns of gameplay :). Net effect is a wave of colonization spreading out at around 2-3% of c.
The colonies are largely independent of each other; it's unlikely that they're all going to annihilate each other, or simultaneously annihilate themselves. The galaxy's 100,000 light-years wide, or about 300,000 light-years in circumference. The whole thing should be colonized within 10 million years. At less than half a percent of c, we're still talking about a hundred million years.
That's an eyeblink, astronomically speaking. If it was going to have happened, it should already have happened. The universe has been around for 13.6 billion years. Life's been feasible for around 10 billion of those years, after the first wave of hydrogen/helium stars went supernova and gave the universe enough heavy elements to form planets and to do interesting chemistry. Our little rock has been around for around 4.5 billion years, and inhabited for 3.6 billion years of that time. It's hardly a stretch to think that something else started 0.1 billion years ahead of us. (or got started later, but skipped the billion-odd years of time that our biosphere spent dicking around with unicellular life in the precambrian era.)
We're talking about 0.1 billion years to colonize the galaxy. Trivial for an advanced technological civilization. Assuming we're not the first, it should have happened by now. The fact that it hasn't happened is an indication that we're the first. (And as a corollary, that however common life may be in the universe, intelligent life must be mind-bogglingly, astonishingly rare. We've only been sentient for a million years, and smelting metal for a few thousand. An eyeblink of an eyeblink of an eyeblink.)
Re:Why (Score:5, Insightful)
It just doesn't make much sense to take an expansionist view of space travel, unless maybe your species is very, very patient and stable. Any colonists you send far out, you will never have meaningful contact with again. At that point you might wonder what the point of "conquering" new systems is, in terms of nationalist-type expansionism.
Re:Why (Score:4, Insightful)
Most civilizations would not expand very quickly at all, probably not much faster than they absolutely have to. Granted, you might imagine a very adventurous species that would send ark ships thousands of light years away just for the hell of it, but for the most part that seems unlikely, perhaps used as a last chance for survival. If any faraway colony is, in essence, as good as a different civilization, it makes little sense to send ships out very far. Moving out of a solar system would be a rare incident, mostly only taken up when the survival of the species is threatened. Just as you can't currently think of colonizing other planets as a solution for overpopulation on the earth - you just can't lift enough people off the planet for it to make a difference - you can't with any reasonably conceivable technology think of colonizing new solar systems as a solution for lack of resources or living space. You can send colonists out, but that's the last you'll see of them, and any problems you have in your own system, you will need to deal with there.
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Depends on how long it takes a Martian colony to become self-sufficient. Stuff can grow pretty well in the Americas, and it's not overly hard to extract natural resources. The same cannot be said of Mars, with its lack of atmosphere and magnetic field.
Brains are not a gaurnteed right (Score:3, Insightful)
The dinosuars were doing pretty well as the dominant species for 100 million years without advanced technology, and if it were not for the KT event, they might have been the dominant species fo
ever since moo (Score:4, Funny)
Re:ever since moo (Score:5, Funny)
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The logic of the story is faulty. To assume that capable civilizations would desire space travel is foolish in itself. Next if we do use the assumption that advanced critters would want to explore there is a second problem in assuming that they would not be unusually covert in those explorations. The next huge assumption is that craft or devices sent out to explore would be recognizable as such by humans.
My own perfectly irrational assumptions include
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Personally, I'm still waiting for evidence there is *one* civilisation in this galaxy.
OH SNAP! You certainly told humanity! On a post on Slashdot no less!
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Funny, that's the first thing I thought, too. I hope the friggin' Meklars aren't playing.
Nonsense... (Score:2, Funny)
We should start bumping into Vulcans in about 54 years... Zefram Cochrane should be born pretty soon... then we'll know.
How many probes could be lying under the ocean? (Score:2, Interesting)
Some people might argue... (Score:2)
... that these probes already have and are seen by old ladies and drunks in the Arizona desert all the time!
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Re:How many probes could be lying under the ocean? (Score:5, Interesting)
It is possible that the probes lying at the bottom of the ocean were not designed to get wet because the host planet does not have water at all. Now these probes might be short circuited or something of that kind.
Expanding on this, what if they were looking for a planet like Mars or (harder to detect) Venus? Maybe the probe arived billions of years ago and saw three planets in adjacent orbits with water. Who's to say it would have picked the correct planet?
As for detection, a single object sitting under the dense atmosphere of Venus for 100 million years doesn't exactly pop out at us.
I think that there is a lack of imagination here (Score:5, Insightful)
I remember reading an interesting book called "The Science of Star Wars" that discussed the real life issues with the technology and situations in the original trilogy. This covered everything from the theoretical sciences behind the technologies like lightsabers, blasters, and lightspeed to the possibilities of existence of other life out there. I haven't read this book in a very long time and I don't have access to it at the moment, but I seem to remember it indicating that the odds of finding another planet with water, breathable air, and the exact distance from a sun necessary to help life flourish were so extremely low as to be laughable.
I remember thinking even then how short-sighted that was and how arrogant it seemed.
I realize these things are supposed to be scientific so they use only what they know to be fact, however, I think when dealing with complete unknowns such as the type of life out there or what their technology level may be at, you have to start thinking outside the box and be a bit more imaganitive.
Who is to say, for example, what form other life will take? Would we even recognize it as life if we were standing right next to it? What about their technology? Who is to say that they haven't gotten past the lightspeed issues with relativity and energy required? Perhaps they have stealth technologies... would we even be able to detect them? Just because we don't know how to do it now, and just because our current science says it probably isn't possible, doesn't mean it can't be done.
Re:I think that there is a lack of imagination her (Score:5, Insightful)
We pretty much know what rocks and ice look like. If the aliens aren't spectacularly good at masquerading as rock and ice, we'll recognize them.
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I don't remember the novel it came from, but one SF writer had a bunch of human explorers run across pretty, slowly shifting, crystaline patterns floating as thin films on the surfaces of otherwise sterile oceans in a chemically exotic environment. Human initial response was pretty much limited to 'Ooooh shiny!" After weeks of scanning the whole planet and crunching numbers, one of the ship's scientists announces there is a sophisticated civilization with billions of participants encoded in each crystal mat
Re:I think that there is a lack of imagination her (Score:5, Informative)
Later incorporated into his novel Diaspora
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Not laughable.
there are over 70 sextillion stars. If the chance are 1 in a trillion we would ahve a galaxy teaming with intelligent life; however, That's over the period of 13 billion years.
All evidence point to species becmoing ectinct sooner or later. so what are the odds of an intellegent species surviving to a point where they can send out probes?
Even if a civilization created a probe that is trying to be fouind, it would still be very, very, very hard to detect, assuming it gets close enough to be dete
Howdy Doody's passed the house of Aquarius. (Score:3, Interesting)
That's a great line from the lyrics of a Clutch song, and it's forced me to ask the question: "What would life be like today, if the moment we invented radio/television we started receiving 60yo broadcast transmissions from another planet?"
How 3 Dimensional of you... (Score:4, Informative)
Hrmm (Score:2)
So when did this mysterious 50 million years mark start? yesterday? 10 million years ago? 49? 65 million years ago?
Greed Effect (Score:2, Interesting)
Maybe there was a civiliation considerably more advanced than us, but whose to say they didn't destroy themselves by electing leaders who entered into wars over natural res
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You're thinking of the Drake equation:
N = R* x Fp x Ne x Fl x Fe x Fi x Fc x L
http://en.wikipedia.org/wiki/Drake_equation
Without giving a lengthy description, at the beginning of the project that would grow into SETI, they asked more or less the same questions and decided that it really came down to, "What are the odds that after a given species invents radio, they invent nukes and destroy themselves?" The equation is intended to predict the number of advanced civilizations in the galaxy at any given time,
FYI... (Score:3, Informative)
We still haven't killed ourselves.
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Still alive... still alive...
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Slow pace? A mere 100 years ago, we were just beginning to experiment with heavier than air vehicles. Today, we are driving RC cars around on other planets. It may seem 'slow' to the gottahaveitrightnow mindset of today's younguns, but 100 years is a drop in the bucket.
How long was it between Columbus and the landing at Jamesto
Probes (Score:5, Insightful)
I am curious as to what evidence these alien probes would leave if they don't land and stay on a planet. If they just fly around, collect data and phone it home we would never see them.
Even landing, unless they landed on Earth, our Moon or Mars, how would we see it? I'm not even certain our own probes can spot our own rovers on Mars. Lets say they did put a probe down on earth (like our mars rover) say recently, like 100,000,000 years ago; it could easily be hidden under a kilometer of dirt and rocks and never be found. Time, like space, is vast.
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Yes they can. At least some of those that are in Mars orbit. There are some nice pictures of the landers, the parachutes, etc.
Assumptions (Score:3, Insightful)
This assumes a sufficiently advanced civilization could survive itself for a sufficient span. Taking the only advanced civilizations we know into account - the human race - I don't see how its realistic to expect survival into the "millions of years" range.
I'd put forth that any civilization advanced enough to develop such technological advances, would kill itself long before such technology develops. Our current modus operandi is not sustainable millions of years out, and using the human race as a basis, I think it laughable to consider the possibility of survival for millions of years. The oldest human remains are what, about 160,000 years old? Might we be getting ahead of ourselves speaking about intelligent life colonizing the galaxy?
Crocodiles on the other hand - those bastards are believed to be around 200 million years old. They've exhibited a much better understanding for what it takes to survive long term (of course we're doing a pretty good job of killing them too - you can say people are bad at somethings, but everyone has to admit we're really good at killing other stuff). If crocs could somehow work space travel into their lifestyle, this could lead to something...
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you can say people are bad at somethings, but everyone has to admit we're really good at killing other stuff
Or we'll kill them.
Advanced Alien Behavior (Score:5, Insightful)
I mean it's kinda hubristic to assume they want to talk to us. After all we may study chimps but we don't go out of our way to show up in the middle of nowhere to say hello. That leaves the question of why we don't detect communication leakage, e.g., radio signals they use for communication. However, not only is it not obvious that they would use radio to communicate, or that we could recognize such signals, but it's not even obvious they would bother to colonize the galaxy or communicate between planets.
For example suppose that sufficiently advanced civilizations transform themselves into some form of 'computational' life. Such a civilization couldn't care less about planents or minerals. What would matter to them is processing power per unit volume. It would therefore make sense for such civilizations to seek out the regions with the highest energy density that would allow them to access the most processing power. Rather than racing around the galaxy in starships and living at the same crawlingly slow pace we do such civilizations might exist entirely in the high energy regions in neutron stars or around black holes. So why would we expect to meet them. Hell, even if they care about meeting aliens too the aliens they care about are probably the ones who already inhabit similar regions.
Even if we think it's reasonable to assume aliens are sending messages all over the galaxy the more efficiently such messages are encoded the harder it will be for us to identify them. The closer such transmissions approach the Shannon limit for the communications channel the harder they would be to distinguish from random noise (and we don't know enough to rule out a natural source). Also the more effective use they made of their communications equipment the less stray signal that would wash the earth, even if it was encoded in radio instead of neutrinos or something weird (some papers have suggested neutrinos would be a better long range communication method).
The point is that even if we take for granted that there a fucktons of advanced alien civilizations around it just doesn't follow that we should be able to detect them.
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However, not only is it not obvious that they would use radio to communicate, or that we could recognize such signals, but it's not even obvious they would bother to colonize the galaxy or communicate between planets.
Exactly, why would you want to communicate between planets when in a few thousand years after having populated one everybody you left there will forget they're still the aliens? Even their technology would probably start diverging from what you left them with and eventually they'd become a group of organisms looking into the sky to find aliens and wondering why there aren't any ...
... maybe that's why we're so adamant about finding them. Deep down somewhere we know we're aliens and would like to go home no
Does Not Address the Fermi Paradox (Score:3, Interesting)
It's always seemed to me that the major hole in the Fermi paradox is the assumption that technologically advanced alien civilizations would be emitting signals we would recognize.
In common with authors the wrote the cited paper, and most commentators on the subject (and virtually everyone who claims to have a "resolution" for the Fermi Paradox), the above comment fails to understand the essence of the Fermi Paradox -- what actually makes it profoundly paradoxical.
The Fermi Paradox does not assume that "technologically advanced alien civilizations" (in general) "would be emitting signals we would recognize". The paradox lies in the fact that the Universe is a very big, and very old
Re:agreed (Score:5, Interesting)
Your argument is silly. Buses pick you up from bus stops, not from your house. If you want to get on a bus you have to go to a bus stop. An intelligent civilization on a planet a thousand light years from Earth that has astronomers is going to look up and see a similar sky. Even if their eyes only work well in the infrared they can still build detectors (just like we do) that cover the entire EM spectrum. When they build their telescopes they will find the same things we have. Their radio telescopes will pick up synchrotron radiation, pulsars, AGNs, and the CMB. Their optical telescopes will see the same stars and they'll deduce similar if not the same cosmological and physical theories. An important thing they'll find are the hydrogen and hydroxyl lines in the microwave band. These lines are in the middle of a relatively quiet portion of the radio spectrum. These are both radio emission bus stops.
Any alien radio astronomers will be looking at the same frequencies that our radio astronomers do since they're both looking at all the same phenomena. If they decide to announce their presence to the rest of the galaxy their best bet will be to do so on a frequency other radio astronomers are likely to be looking at. You might catch a bus randomly passing by but your best bet is to wait at a bus stop since you can be reasonably sure a bus will eventually stop there. Interstellar messages don't have to be fully understood or translated to be important either. Simply receiving a coherent signal from another intelligent civilization would provide a wealth of information. For one it says "there's someone out there" and that signal is going to come from a specific place. Other types of telescopes can be trained on that location to try to learn all you could about that civilization or at least the environment they live in. The light coming from the planet traveled at the same speed as their radio signal so atmospheric spectra would be contemporaneous with the sending of the signal. Aliens detecting the Arecibo message would be able to look at Earth and see what it was like in 1974 when the message was sent. Knowing there's a civilization there they could keep telescopes trained on Earth to learn more about us even if they didn't fully understand the content of the Arecibo message.
It also does not matter in the slightest if there exist civilizations with esoteric means of communication. If they exist and want to talk to less advanced civilizations they'll communicate via the lowest common denominator of radio or optical transmissions. If they only want to communication via their esoteric means then they obviously only want to talk to equally advanced civilizations and we don't have a lot to offer them (at least they don't think we do). We don't really need to worry about such civilizations, we only need to concern ourselves with the ones stopping at the same bus stop as us. This is also why we tend to look for Earth-like planets when talking about extraterrestrial life. Yes some odd creatures with completely alien chemistries might exist but if we wouldn't recognize them then there is no reason to look for them right now. We can instead look for the creatures with chemistries we do understand fairly well and would recognize instantly. Also in the hunt for Earth-like planets we're not throwing away knowledge of all the non-Earth-like planets. If we find some life form in an asteroid or on the Moon with a chemistry completely unlike ours we can dig through our exoplanet archive and look for markers of such lifeforms on planets we found that were like the home of the life form we found. Just because life forms might exist that are unlike us or civilizations might exist that don't communicate like we do is no reason to assume that all life is unlike ours and all civilizations don't communicate like we do.
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1. It assumes that radio signal based communication is the first major communication style developed/discovered by a civilization. It's entirely possible that based on different environmental factors they were never able to get it to work in a reliable manner or through the magic of scientific breakthrough ended up with a different or superior communication style.
2. Any number of religious or cultural decisions could get in the
We went to the moon forty years ago.... (Score:5, Insightful)
...and we haven't been back since. Beyond the question of how long it would take a motivated civilization to expand throughout the galaxy, there's the question of "would they bother?". We don't seem to be bothering.
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@Ktistec Machine: "We don't seem to be bothering."
Chastising ourselves for our lack of will regarding space exploration is all well and good but the fact of the matter is that space exploration is no light matter. It currently requires a great amount of effort, will, economic consumption, and resolve.
That the US was able to go to the moon during the cold war should not be taken lightly. Of course, the only reason we were able to do both things is that we were still coasting on our fortunes gained from WWII
Re:We went to the moon forty years ago.... (Score:5, Insightful)
Re: (Score:3, Interesting)
The only absolutely vital thing to transport is information (since it can't easily be reconstructed from scratch). And hard drives are small these days. There's absolutely no fundamental reason why the technology to build, say, a chip fab needs to take up a lot of room. It's certainly conceivable that you could send a few nanobots
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"all your technology goes away eventually, "
Only if they are incredible stupid and short sighted.
Since they have space flight, I will presume they are neither.
You know when you get there you will need to build an infrastructer.
So you takes some fundamental resource with you.
For example, take what is needed to build a nuclear reactor*.
Build it, now you have power. Then you mine to replenish resources and build.
You don't go through all the technology phases again.
*what ever technology you are using to power t
10 reasons why aliens might not use radio (Score:4, Interesting)
2. War on. Radio silence.
3. Wrong physics. Outside the bow-shock of a sun, radio works a lot different than we thought.
4. Cheap FTL communication happens to be just around the corner.
5. They are life, but not-as-we-know it and don't know about radio. Examples: Dark Matter, Live on a sun, live on a black whole. Note all three of these things are more common (on a mass basis) than planets.
6. Powerful, rich, major religion/government objects to radio and shuns those that use it, trades freely with those that avoid it.
7. Radio is deadly poison to one of the major alien species.
8. Most races are born telepathic.
9. Radio turns out to to cause global warming. (OK, this one is a bit silly.)
10. Industrial processes moved off world act as a radio scrambler/jammer. Races still use radio within their world, but their signals are jammed by the intereference from say the cheap production of anti-matter scramble the signals.
Re:10 reasons why aliens might not use radio (Score:5, Interesting)
To add to that:
If you took a completely alien language, encrypted it. Compressed the hell out of it, then applied 10,000 to a million years of technological advancement to the sending of it, would we even be able to notice it from background noise? Even if radio was still used to send it?
Re:10 reasons why aliens might not use radio (Score:5, Interesting)
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Calvin (Score:5, Insightful)
-Calvin
Orion's Arm (Score:3, Interesting)
Visit Orion's Arm for an idea what populating the galaxy might be like.
http://www.orionsarm.com/ [orionsarm.com]
Why would probes leave any evidence at all? (Score:5, Insightful)
Let alone evidence that would last a million years. A probe could have come through a thousand years ago, hung around taking pictures and measurements for a few years and moved on. We'd never know.
Re: (Score:3, Insightful)
You have no idea what resources a probe built by a civilization 100,000 years ahead of us requires.
Heck, even the assumption that "Probes" as we understand them are needed for data collection is enormously conceited on the part of humanity.
Humans today are as thick as bricks.
Do we try to communicate with the cows and pigs? Heck, we walk among them, breed them, cage them, kill them and EAT them. But they just graze and stand around in a daze as though it were all the most normal thing in the world. We sim
The Great Old Ones Are Out There (Score:3, Interesting)
We Are In Quarantine (Score:3, Interesting)
The dream went on to explain why we see UFOs that don't communicate with us. They are outlaws breaking the quarantine. Humans, said the dream, have unique language abilities unknown elsewhere in the galaxy. A single human could write more and better code than teams of hundreds in the next-best software civilization. So the UFOs are from some of the shadier civilizations out there and they come to kidnap code slaves. They have to stay stealthy or they will get caught.
This was a real dream I had about 10 years ago. And yes, I was asleep at the time. The story is obviously full of holes, it was only a dream after all, but intriguing.
techy (Score:3, Interesting)
I know I'm just being techy, but you can't actually STUDY something until you have at least one example of it.
A lot of cosmological science and just about all exobiological science is completely made-up, maybe I'm just tired of "science news" that is 100% fictional.
Frankly, we have nearly zero knowledge of life in the rest of the universe - it's okay to speculate, just call it speculation.
we are the first ones to emerge (Score:4, Interesting)
Three Simple Options (Score:3, Interesting)
1: God-like* alien intelligence is all around us and they're enjoying the show --or completely disinterested.
2: FTL or even near light speed travel is impossible and we're limited to contact with close neighbors.
3: We're the first technological species in the neighborhood (maybe life and/or intelligence is just incredibly unlikely).
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*They would have tech perhaps millions of years ahead of us
The problem with colonizing the galaxy (Score:3, Interesting)
is that the number of planets that can host life forms is so low in number, that some sort of Terraforming technology would have to be made to make the Mars and Venus type planets more like Earth.
Right now we cannot even control the pollution on Earth that is making Earth less hospitable to current lifeforms.
If there is more advanced life in the universe, they'd have to find a solution to their own pollution as well as invent Terraforming technology. If they don't, eventually they will go extinct.
There is also a good chance that Earth is the most advanced life forms in our galaxy and if other life exists, it hasn't even invented radio devices yet so we can detect them, or they are too far away that radio waves from their planet has not reached Earth yet.
There is also another possibility that maybe life on other planets skipped radio if they are advanced enough and use some other way to communicate that we cannot detect, or they use radio and use an encryption that makes it look like natural random signals to less advanced life forms.
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What kind of asshole would put all that huge expanse of the universe out there and so utterly cut us off from it?
One persons asshole is another persons practical jokester.
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Re:0.1 the speed of light? (Score:5, Informative)
We run through the Kuiper Belt where we collide with a tiny pebble that is lazily orbiting our solar system
The relative velocity of a bullet, fired from a low velocity pistol, when it hits something is generally between 300meters/second and 600meters/second. Now imagine a bullet with a relative velocity of 150,000,000meters/second. The problem isnt the space drives.... its that the "vacuum of space" has shit in it.
Re: (Score:3, Insightful)
This craft sweeps a volume of space equivilent to 15 billion cubic meters / second. [google.com]
Thats 9 quadrillion cubic meters / week.
The *nearest* star will be 8 years away, at 0.5c.
The chance of hitting such a small piece of rock approaches 100%
You need religion in the mix for this to work. (Score:5, Insightful)
Otherwise, societies are too self-absorbed to dedicate those sort of resources to a goal that will have ZERO benefit to them or their descendants.
It sucks for scientific types, for sure, but the best way to get the masses emotionally committed to space flight and space exploration is through religion. There's no more historically proven way that motivates people to build and explore for future purposes than the prospect of being able to worship your lord and impose his law as your religious customs see fit to do so. In 1620, it wasn't a bunch of scientists on board the Mayflower, it was a bunch of religious fanatics. In my site I'm going to go all out religion for space exploration as a national priority and argue in this order:
a) The Lord gave us the vast resources of the Heavens to use.
b) The Earth is a crowd and dank cesspool of sin.
c) You can establish a more Godly society on another planet.
d) You can re-create the American Experiment the way the founding fathers intended.
Paradoxically. . . (Score:3, Interesting)
I don't think that Fermi's Paradox is all that paradoxical either. I just think he was closed-minded, unimaginative and perhaps a tad (or a whole lot) conceited. (Sorry, Fermi.) --But I still think you're making a rather large assumption.
We crossed oceans without first getting comfortable in our dangerous, leaky, rat-infested sail boats. Planets have wonderful, big, open spaces, wind and rain and snow, natural sunlight, natural fauna and geographic features which appear according to chaotic systems we d