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SETI Predicts We'll Find ETs by 2020
FTL writes "Based on the Drake Equation, Moore's Law, and the Allen Telescope, a new prediction has been made that Earth will make first contact with aliens within 20 years. Of course once we find the first aliens there's the question of can we decode their signals, would they spot our reply, and what's the lag time."
It is 2004, right? Wouldn't that set the date to 2024?
there's the question of can we decode their signals, would they spot our reply, and what's the lag time
And is their primary goal "To Serve Mankind?"...
they are beta tesing BOINC. name one beta test that's gone smoothly. exactally.
BOINC is much faster and more effient, can support multiple dist. computing projects as well.
a seti workunit used to take about 7:35:00 on my comptuer at work, and now it's under 4:30:00. thats a pretty big improvement.
Making the large assumption that an alien race will go through a similar radio transmission curve, and considering the fact that we don't know how far away said alien civilization is, the chances of us finding them between now and 2020 seems very remote.
For all we know, humans might rank at the cattle level on a galactic scale. You know - really stupid and very, very tasty.
Good heavens Miss Sakamoto - you're beautiful!
I've been wondering this...and all of you people that think you're smart might be able to figure this out for me. SETI uses radio telescopes to search for E.T., right? Now, I understand that these radio telescopes don't just search for AM/FM radio signals, but basically waves within the full broadcast spectrum. So they're looking for AM/FM, TV, CB, Wi-Fi, wide band, short, wave, cell phones, etc. So I guess the basic thinking is that any intelligent race will use radio signals of some sort. How long have humans been using some kind of radio signals? In the general scheme of things, a very brief time. How much longer will we be using them? Is this something that will be with us forever, or will it die out as our technology advances? Assuming our technology will advance, somehow, to exclude broadcast signals, our planet, from space, will become rather quiet. Also assuming that all intelligent life evolves along a similar timeline, we can assume that these other planets will emit radio signals for only a brief period of time. But somehow we're assuming that that time will somehow coincide with our own. It makes finding a needle in a haystack even harder when the damned needle keeps moving around. Enlighten me. How can SETI possibly work? (That said, I do have the SETI@Home software running on all of my machines...so I'm hopeful.)
What complicates matters is the assumption that a technological civilization that has this technology is still primitive enough to pump out massive amounts of EM radiation in all directions to communicate with other individuals around them.
Even here on primitive ol' Earth we can see where EM communication is going... directed beam, spread-spectrum, low-power wireless mesh, encrypted (ie. reandom-looking) digital, and that's all a mere 100 years or so into this radio thing. How many of the 10K-1M civilizations out there do we hope to accidentally catch in this tiny window of radio naivete? And since it will take 100-1000 years to send a message back, does anyone seriously think they'll still be listening attentively to their little alien vacuum tube sets when it gets there?
Though you might have been kidding about beeing affraid about the evil alliens coming to visit and do evil things to us like take away our freedom (or worse, steal our MP3's), this does seem to be a bit of an unfortunate trend in modern thinking. Just because they look different, think different and have a different believe system we don't have to instantly nuke them when they are within reach.
I for one welcome our new green-multi-mouthed homosapienphobic omnivore doomsday-device-wielding neighbours!
I read a book when I was 8 that said we'd contact aliens by 2010-2015. I've been holding my breath ever since. They also wrote about the flying cars, moon bases, and solar power satellites that we've been enjoying these past 4 years or so... I just wish I didn't live in such a back-waters part of the country that's still driving around on 4 tyres.
Shostak took that into account. He estimates between 10,000 and 1,000,000 radio-transmitters (planets with intelligent life). Considering the number of stars in our galaxy alone (100 billion according to the article), that only means we'll have to look everywhere in the galaxy to have a good chance of finding something. In the end, the uncertainty from the Drake equation doesn't affect his estimate at all.
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Yes, you have to try to pick valid values for the variables, however, many of the variables are rapidly becoming well defined:
I /d rake_equation.html
http://www.activemind.com/Mysterious/Topics/SET
If we consider only our galaxy:
N = N* fp ne fl fi fc fL
of which we have answers for
N* = number of stars in galaxy (~100billion)
fp = fraction with planets (at least ~20%)
ne = number planets per star that can spawn life (???)
fl = fraction on which life evolves (??? but if we discover life evolved on mars and earth separately we'll have to assume this is reasonably large, so this might be settled soon)
fi = % where intelligent life evolves (???)
fc = % which communicate (???)
fL = % of planetary lifetime during which communication takes place (currently we can assume this is a small non-zero value, and the longer we use radio waves the larger we can assume this value is).
fp is rising rapidly as we discover more and more extrasolar planets.
fL is rising steadily as our radio emitting civilization persists.
ne may be more accurately guessable once we find out if mars, venus or europa harbor or ever harbored life.
The key to the drake equation is that N* is a very very big number. And now that we know fp is not small (up to a few years ago many people argued that fp would be close to 0) we know that the other fractions need to be quite tiny to avoid having radio communicating civilizations other than our own around.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
They are also finding out about how easy it is for life to exist in even the harshest of environments. Life is looking more and more simple to create and sustain than we ever thought in the past.
Intelligence is not all that important for survival in general, but survival from other slightly "better" creatures. Is a rabbit more intelligent than a fox when it runs faster? Maybe not, but the wolf may be more intelligent when it works with 5 other to catch some rabbits.
Ants, on the other hand, have been around for millenia, yet are very simple creatures.
Not to insult, but that statement display a fundamental lack of understanding of the known processes of change over time with modification and natural selection. (AKA evolution)
An ant doesn't get smarter or more complicated over time just for the hell of it, it needs a reason. (and no, the ant species doesn't decide this, it just common to anthropomophize the subject). If it never needs to cut leaves, it doesn't benefit from mandibles, so they never become a survival trait to pass on the the next generation.
And we are not that unique. We share so many attributes and have so little range of difference with some other species that denying the evidence smacks of agenda and dogma.
Sig
Appended to the end of comments you post. 120 chars
You've been beaten to this. It's called the "preemption scenario" (not the preemption doctrine). The idea is that it would take somewhere on the order of tens of millions of years for one space-faring species to colonize the galaxy - which is a small enough fraction of the age of the galaxy's stars to suggest that it should already have happened. But there's a lot of other variables: for instance, it's possible that the sun's population cohort is the first in a heavy-element rich enough environment to evolve life, etc.
At this point, we're reduced to problems of biology. We have easily produced amino acids in recreations of primordial Earth, so clearly organic compounds in general are not difficult. Similarly, life on Earth has proved to be ridiculously tenacious, reproducing and thriving in even the most disgusting conditions. Bridging the gap between amino acids barely capable of forming proteins and self-reproducing molecules is the only real unlikelihood here. But there are a number of plausible theories that don't involve seeding by extraterrestrials, merely time and chance.
If we assume that life can easily form on planets that can support it (which would definitely be backed up by the discovery of ancient life on Mars), it is highly reasonable to conclude that among the stars, life is as commonplace as dirt.
The development of sapience is probably the most unlikely item on the list. There's nothing about primates that tends towards intelligence that hasn't happened before, it just took a combination of the right evolutionary and environmental coincidences. On Earth, the inner workings of DNA and RNA biochemistry got about as good as it ever will eons ago. But it still took a billion years of recombination for sentience to develop. Whether or not it occurs elsewhere is something we'll just have to go and see for ourselves, but with (potentially) trillions of planets and eons upon eons of history to work with, the odds are pretty good.
Dyolf Knip
The prediction makes some sense, assuming that there ARE aliens to begin with. I personally believe that Earth is the only planet in the universe with life. I won't be at all upset, however, if I turn out to be wrong.
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The exponential nature of tech growth implies that we are like apes to a civilization even 100 years ahead of us,
Many of the key results of the 20th century involve the limits of what we can do. Godel incompleteness, and the speed of light to name two big ones. There is no indication at all that any civilisation, no matter how advanced, will be able to overcome the lightspeed problem and make us look like ants.
technology to visit the entire universe at will ("c"restrictions from the current physics knowledge notwithstanding).
You want the lightspeed thing to go away, don't you? Unfortunately wanting counts for nothing, and there's not a shred of evidence for that, and plenty against. Even given nigh-infinite knowledge, physical limits are physical limits.
Many, including me, believe that within about 100 years, a civilization like our would have the technology to visit the entire universe at will
It's entirely possible that a civilisation like our will, in 100 years, have A-bombed, bio-plauged, chemically poisoned or just polluted itself back to the early stone age. Or worse, wiped itself out entirely. I'm all for progress, but dude, go easy on the prozac.
My Karma: ran over your Dogma
StrawberryFrog
If it is so incredibly improbable that life came into existence on it's own, and therefore must be created, this brings up another question.
If we're too complex to have occured on our own, thus requiring a creator, must not that creator be much more complex, and thus even more unlikely to exist? To follow the same logic, you end up with an infinite regress of creators, with one at the end that is both infinitely complex and infinitely unlikely to exist on it's own (which can also be called impossible).
Why do you give that more complex being a pass to exist no matter how unlikely it is, but yet not do the same for the more likely to occur life that obviously exists on this planet?
"You know your god is man-made when he hates all the same people you do."
No, what we lack is precise knowledge that the earth is special. That is, we don't know the probability by which a planet has a big moon, or that it is near enough a star to sustain life. We don't know the very parameters of life, except that it exists on earth in great varieties.
Absent this knowledge, it is incorrect to assume that the earth is special, any more than a lottery winner should see herself as (too) special. If you only know of one lottery winner, then you'll be misled as to how often somebody wins the lottery if you try to extrapolate based on that ignorance.
The correct approach is to assume that we are one instance of random behavior, that the earth just happened to be so far from the sun, that we just happened to have a big moon, that we just happened to not have collided (yet) with another big object. We are likely a very special planet, but we really have very little clue whether we are special enough to claim exclusivity.
Once you accept this randomness assumption, then the probability of life (and therefore intelligent life) on another planet is entirely a matter of how many planets there are out there. The more, the likelier.
Remember that if you're a one-in-a-million kind of guy, there are more than 1,000 people in China alone just like you.
We can't currently pick up ET signals equivalent to what Earth is broadcasting to space, even if they were coming from Alpha Centauri; they're just too weak.
This is an analog problem of signal to noise ratio, far more than anything else, so faster processing won't help a bit.
A cryogenic Allen array (to minimize thermal noise), especially in space far from Earth, or on the far side of the moon, would help a tremendous amount.
Usually discussions about SETI itself don't bring that up, because of issues of optimism and such, but it was easy to find web hits on the eseentially identical question: can ETs pick up Earth signals?
"No", says this Seti League guest editorial "ET Detection of Earth TV Unlikely" that goes into a little technical detail.
Similar comments by John Dreher, Staff Astronomer, SETI Institute, although he goes on to assume that ETs would be able to pick up weaker signals than humans are able to -- assuming implicitly that ETs will have better analog technology than we do (maybe they do, but that doesn't help us to do the same).
What about ETs actually beaming a signal at us? Maybe they do so to all nearby stars, one by one. Maybe...would we do that?
"...it has been agreed by all relevant groups that we should not be actively sending out messages to try to reach other civilisations", says another page
Ok, so we would not be so foolish as to attract undue attention from an unknown and possibly hostile galaxy, but maybe ETs will be more naive than that. Or a lot more confident (play ominous music here ;-)
So, bottom line, this is a cool topic, but are we planning to build a cryogenic Allen array in space in the next two decades?
I think we should, but any predictions really should be based largely on that one issue.
P.S. the recent lab verification of photons having orbital angular momentum, able to carry arbitrary amounts of information per photon, implies a new medium we'll need to check for ET signals. Maybe that's what all advanced civilizations use.
See e.g. Photons Spin More Data
Professional Wild-Eyed Visionary
My guess is that ne and especially fi are quite small. In our system, we have ne being 11% (maybe 22%). Just judging by the time fi applies to this planet (150,000 years versus 4.5 billion years) we're looking at about 1/30,000. The assumption that intelligence is inevitable just doesn't hold water with me, either, as life does not need intelligence to survive, e.g. bacteria and insects.
Also, because most of the stars in the galaxy are in the core, where the radiation effects are so much greater that the only likely life is extremophilic, the number of stars with habitable planets (ne) is probably quite a bit smaller than you suspect.
Finally, heavy elements, like oxygen, carbon, silicon, iron, etc., are not exactly common. As I'm sure you know, they are only formed in other stars, and the only way they get back out to interstellar space is through supernovae or maybe planetary nebulas.
Dream your Star Trek dreams. The greatest probability is that we are alone, in terms of intelligent life, in this galaxy.
>Or if you have the right chemicals present on a planet, the formation of life may actually be likely. Who knows?
We know, because we know what the right chemicals are, and we know the laws governing their reactions, and we can calculate the probabilities of formation. Granted, it's senior-level college chemistry, but not impossibly difficult to figure out.
And I'm sure you can point me to the studies that show that the way life is on this planet is the only possibile way life could ever exist, right? That they've tried all other possible combinations of elements possible, or at least proven that all those other permutations cannot possibly ever in any combination lead to life? After all, claiming that life as it is here is the only possibility is an extremely huge claim, so you must have evidence supporting that claim, right?
Or are you just saying that because it throws your assumptions that life is impossible to form on it's own into chaos? That's what I have to guess, because I don't believe they've ever proven that life as it is here is the only possible way for it to be.
"You know your god is man-made when he hates all the same people you do."
If you watch too much SciFi, you might get brainwashed into thinking that aliens might possibly look like humans.
But the truth is, only the evolutionary history of earth could have produced humans. Slight changes at various points in our history could have radically altered what came to be the dominant life form and if that form was even all that bright.
Some stuff I was watching on the Science channel recently explained that it was an ice age that created selective pressure in favor of hominids who were smarter, because our ancestors had to adapt to a changing environment faster than evolution could adapt. Only the hominids who could IQ their way around the problems (ie. invent clothing) were able to survive.
Now, when it comes to aliens who evolved in an environment that is completely different from ours and with little or no possibility of us having common ancestors, you really can't expect much similarity.
Now, we do live in the same universe with the same physical laws, which means they probably use some of the same chemistry. For instance carbon seems to be a much better basis for building life forms than the alternatives. Also, liquid water is a much better environment than the alternatives.
We have to ask, for instance, if life can evolve in radically different temperature ranges. Can life evolve in liquid methane? How about molten iron? We do see some rather interesting "extremopholes" here on earth, but I suspect it's easier to adapt to an extreme environment than to evolve there in the first place. (That is, there may be life still on Mars from when it had liquid water, but it's a completely inhospitable environment for abiogenesis.)
We assume that their math will be similar. I mean, if their technology is advanced enough that they could do, say, quantum computation, and they have electrons whose spin they can manipulate, well, presumably, they would have a concept that allowed them to distinguish between one electron, and then two electrons, and then three electrons. That is to say, electrons are discrete quanta, so if you're going to deal with them, you have to be able to count them. So we can assume that an alien culture will have that. But can we really assume that? What about a world 100% covered in water where live evolved in such a way that there aren't separate organisms, but really every living thing is just a part of the same continuous organism, where everything is connected in some way. If you evolved to live in a world where you perceive everything as continous and you therefore have no concept of discrete objects, then can you count? (I agree that there are some lousy assumptions here, but go with me here.)
Much too much of our world seems fundamental to us because this is the environment we evolved in. For instance, predators had an effect on our evolution. Naturally, the aliens would have different evolutionary pressures... throughout all of the billions and billions of years in their evolution, completely different from ours. So, consider a world, for example, where metalic iron is sticking out of the ground all over the place. Think about how inhabitants would evolve to make use of this ubiquitous natural resource the way humans evolved to make use of wood and animal bones. (Or more fundamentally, how our cells evolved to make use of carbon compounds as building blocks.)
Alien life could be so different that we might not even recognize it as life. No matter what you conjecture about what alien life might be like, if/when we ever do discover it, it'll be nothing like what you expect.
>devil's advocate
/devil's advocate
So what we have here, if I am not mistaken, is not science but a new religion.
In other words, the people at SETI who believe like Shostak does are assuming the existence of something for which there is no proof.
Sure, they use scientific tools in their work; they couldn't get by without them. They may apply the scientific method to problems that they encounter but their core motivation is the search for something that they already believe exists. They are using faith in something (without a shred of proof) as justification to spend millions of dollars, countless man hours, and TONS of processor time (SETI@home).
Seems like a total waste of time to me. (That is unless they find some!)
When the only tool you have is a claw hammer every problem starts to look like the back of someone's skull.