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Brainstorming Clever Ways To Detect Alien Civilizations
Phoghat writes "In what is starting to become a familiar theme, researchers have speculated on what types of observational data from distant planetary systems might indicate the presence of an alien civilization. Potential indicators of the presence of an alien civilization might include: atmospheric pollutants, like chlorofluorocarbons – which, unlike methane or molecular oxygen, are clearly manufactured rather than just biogenically produced; propulsion signatures – like how the Vulcans detected humanity in Star Trek: First Contact; evidence of stellar engineering – where a star's lifetime is artificially extended to maintain the habitable zone of its planetary system; or debris created from asteroid mining."
Potential indicators of the presence of an alien civilization might include: atmospheric pollutants, like chlorofluorocarbons â" which, unlike methane or molecular oxygen, are clearly manufactured rather than just biogenically produced
Clearly? Maybe here on earth. Who knows what natural processes exist elsewhere.
I was going to go with the large orbital rectal probe manufactory...
Dyson spheres (or swarms) would probably be the best way to detect an advanced civilization, especially a Kardashev Type II or Type III civilization.
In a Dyson sphere (or swarm) a civilization surrounds an entire star to capture most or all of its luminosity; severely cutting down on its optical luminosity but accentuating the IR luminosity. (The physics of a rigid sphere surrounding a star are pretty challenging, and some sort of swarm or cloud seems more likely, at least to our limited technological understanding.) So, to hunt for a Dyson sphere, you look for objects with an unusual excess of IR, and a lack of optical light. The IRAS IR satellite was used to search for Dyson spheres within ~ 1000 light years of the Earth (producing a handful of so-so candidates). Carrigan calls these sorts of searches "Interstellar Archaeology." They have one great advantage in that they don't require any cooperation from the other end (i.e., no beacons or other signals).
As it happens, I have recently speculated that "Object X" in M33 (the Triangulum Galaxy) could represent the signature of a Dyson sphere / swarm from 3 million light years away. If this (unlikely) possibility were to be true, it would represent the signature of a Kardashev Type III or near Type III civilization. Interstellar Archaeology is the only possible form of SETI across such vast distances.
I agree, we should search for things we can't think of
Snowden and Manning are heroes.
At this point, funding is more important than brainstorming. The Allen Array which does much of the basic SETI work is going to be essentially inoperative for about a year due to a severe shortage of funds. See http://www.cnn.com/2011/TECH/innovation/04/25/seti/index.html?hpt=C1. Right now, the main thing that is needed is cash not more ideas. So go over to SETI.org and donate.
Stellar engineering!?! Any civilization capable of that would be capable of finding another planet.
And propulsion signatures, Really? What exactly would that look like?
The whole thing reads like someone watches too much TV.
Gases in the atmosphere are about the only thing that can be remotely sensed. But I'm sure someone could imagine a non-intelligent life form that could emit chlorofluorocarbons or just about anything else anyone would care to associate with civilization on earth.
And Dyson Spheres. Yeah, that might work. Any civilization that could pull that off would already be HERE, probably farming US.
You might have far more luck detecting a civilization at about the same stage as our own, by the debris field of dead satellites orbiting various planets and moons. But that requires getting closer than we have the technology to do.
But the article begins with the big hand-wave:
Currently – apart from a radio, or other wavelength, transmission carrying artificial and presumably intelligent content – it’s thought that indicators of the presence of an alien civilization might include...
It seems to me that radio transmissions and artificial light sources would be likely used by most civilizations at one time in their development, simple because radio and light occur naturally from many sources, and "discovery" is easy. Either or both is likely be used, even if only briefly in any civilization of planet dwelling creatures.
I don't think its fruitful to set about detecting Dyson Spheres when the radio would have reached us long before their sun dimmed.
Sig Battery depleted. Reverting to safe mode.
1) Rotation wobbles more on Friday nights
2) Neon light from dark side
3) Traces of THC in the upper atmosphere
4) SETI calls go into voicemail
If the Universe is cyclic and there was another universe before our "big bang", one thing we could do is see if the particles around us have some kind of signature to them that would be unexpected.
A couple problems here.
1) What works in Star Trek: TNG cannot be relied upon to work in real life.
2) The idea of a cyclic "Big Bang" is not consistent with the current understanding of the universe. Thirty years ago people took that concept semi-seriously, or at least didn't have a concrete argument against it - but that was back when they thought the universe's expansion was gradually slowing down rather than accelerating.
#DeleteChrome
This step is simple: invent an FTL method of communication.
The reasoning is also simple. If we can have FTL then it is a given that all developed civilizations are using it. Radio is simply too slow. We don't use pigeons anymore to send messages, do we? So why do we expect an alien civilization to spend terawatts of energy and thousands of years to blast radio signals into space?
But if we can't have FTL then pretty much we are prisoners of our star system. Perhaps generation ships can export our genes to other stars, but that is unlikely, and we will never [in practical terms] know how they fared. Ping times of thousands of years are simply out of our time scale, until we all become cyborgs or beings of pure energy.
So that's why FTL is the only possible solution. Anything less is just a waste of money and effort. This effort should be invested into science, in every way possible. Even if FTL is absolutely impossible in our Universe, perhaps we will find a neighboring Universe with physical laws that are more to our liking.
Just look for anything out of the ordinary, and once you find it, try to come up with an explanation. This way you'll not only find life (if it exist) but also other interesting phenomena.
All the planets combined are a fraction of one percent the sun's mass. I don't think Jupiter will cut it.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
There are at least two sites on Earth known where natural deposits of uranium were pure enough to have undergone a thermonuclear process of the kind found in a nuclear reactor. Although improbable, it is certainly possible for an entirely natural nuclear bomb to arise. It is, agreed, exceedingly unlikely but all the processes required do exist in nature and therefore must combine somewhere, at some point in time, in just the right way.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
What an interesting post, I've thought the same things, especially about colonising our own solar system. Once we get there then we can try to figure out the next step of colonising the galaxy.
I was also considering a situation that *if* there were other civilisations that launched robots to explore the galaxy based on their own versions of AI could they combine over time. Could there ever be a situation where 80 percent of the Galaxies intelligent life is "artificial" and 20% has evolved naturally. Imagine if that is what our AI enhanced explorers discovered.
My ism, it's full of beliefs.
> Can we really extend the life of our own sun? I can't even begin to calculate how that would work...
Well, for one, we should start using it only when it's dark outside.
No, a "rational" society would look at the costs of interstellar travel and conclude that any attempt at a mission to another star was ludicrously overpriced and had absolutely zero practical value in any meaningful timeframe.
And now we know why suicide can be a rational choice.
If I have been able to see further than others, it is because I bought a pair of binoculars.
The main problem, however, is not technical - the trip will take 40-45 years, and youngsters who paid for it will be senior citizens when the probe returns. Politically, in a democracy, the majority of population will not buy into this project. You need an enlightened dictator to do this.
Dictators are never enlightened. And democracies are perfectly capable of making long term plans.
To have a right to do a thing is not at all the same as to be right in doing it
It isn't. The Hiroshima bomb was a uranium bomb. It didn't use plutonium at all.
In terms of geometry, what you'd need is a naturally-occuring uranium deposit that contained sufficiently few impurities that it had achieved a self-sustaining natural reaction, both on the ground and on the meteorite. We know the first one is possible because we've found such places. Since it can occur on the ground, it is reasonable to assume it can happen in space under suitable conditions. You also want the deposits on the planet to have undergone the geological process of "folding" (where layers of rock are bent out of shape - very common thing to have happen). The more extreme the fold (and it can get very extreme indeed) the better.
A slightly less favourable geometry would need a steeper angle of incidence, at least the way I was picturing it, but under suitable conditions a more energetic impact would likely work as well. So we've doubled the endless possibilities.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Not really funny. We're a species that's basically newborn to technology and not even really spacefaring in any significant fashion. We're not looking for aliens like us, but for aliens a bit further along that path. Or rather, we're looking for any aliens, but most of the ones we'd expect to find would be technologically more advanced, because it'd be darn near impossible to be less advanced and still be detectable.
The Quirkz Handbook of Self-Improvement for People Who Are Already Pretty Okay
Change seems to be the only constant of life. Look for a change in atmospheric composition, in RF "noise", in anything we can measure really. The galactic equivalent of a motion detector. Not all change represents life, but it does represent something worth investigating. And, of course, the change might not be occurring on a scale we can measure in a short timeframe (where short would be less than our average lifetime), but it would almost certainly be faster than traveling anywhere with existing technology.
Anything else -- the absence or existence of certain elements -- is even more speculative than postulating a cause for change. The only exception might be something we can be reasonably certain hasn't occurred naturally, such as a signal carrying intelligence (modulation), which is the whole drive behind SETI. The problem with only looking for modulated EMR, is that it limits the domain to strictly intelligent life, which, while extremely interesting, could well be too high a threshold.
The other problem is that given the vast distances of space, anything we discover will be ancient history at best, and quite possibly long gone. The only way we're likely to actually communicate with another intelligent species is if they happen to be remarkably close by, or if one of us masters the manipulation of space-time.
https://www.eff.org/https-everywhere
Shouldn't we be trying to detect life first? I've always wondered why we haven't detected absorption spectra for chlorophyll or a similar material (I read recently about the possibility of grey/black leafed plants) in space around stars. If plants are black then they won't leave much reflected light to detect.
Wouldn't moving to another star be easier than moving something heavier than the earth?
Of course I do not recommend WE do this, as Aliens may not be friendly.
But yet you suggest other civilizations might realize this is a great way to let others know, but be too dumb to realize the dangers?
The amount of sulfur needed prevents sustainability of such a project over the time span needed for detection by any other intelligent life forms. How often do WE do spectral analysis on any given random star?
Sig Battery depleted. Reverting to safe mode.