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Space Science

Hairspray Could Help Us Find Advanced Alien Civilizations 211

Hugh Pickens writes "Charles Q. Choi reports that hairspray could one day serve as the sign that aliens have reshaped distant worlds because one group of gases that might be key to terraforming planets are CFCs. 'Our hypothesis is that evidence of intelligent life might be evident in a planetary atmosphere,' says astrobiologist Mark Claire at the Blue Marble Space Institute of Science. CFCs are entirely artificial, with no known natural process capable of creating them in atmospheres. Detecting signs of these gases on far-off worlds with telescopes might serve as potent evidence that intelligent alien civilizations were the cause, either intentionally as part of terraforming or accidentally via industrial pollution. 'An industrialized civilization will be one that will use its planetary resources for fabrication, the soon-to-be-detectable-from-Earth atmospheric byproducts of which could be a tell-tale sign of their activity,' says astrobiologist Sanjoy Som. CFCs can be easily recognized in planetary atmospheres because their atmospheric 'fingerprint' (i.e. chemical spectra) is very different from natural elements, and are a tell-tale sign that life on the surface has advanced industrial capabilities. Using state-of-the-art computer models of atmospheric chemistry and climate, researchers plan to discover what visible signs CFCs and other artificial byproducts of alien terraforming or industry might have on exoplanet atmospheres. 'We are about a decade away of being able to measure detailed compositions of the atmospheres of extrasolar planets,' says Som."
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Hairspray Could Help Us Find Advanced Alien Civilizations

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  • by staltz ( 2782655 ) on Tuesday November 27, 2012 @09:08AM (#42104453) Homepage

    Detecting CFCs applies well if you imagine that aliens are human-like. But real aliens can in reality substantially different than humans. The Universe is weird enough to allow some surprises.

    I've read some news about some odd planets floating somewhere. One planet is almost entirely sugar, and there's some sort of nebula that is basically alcohol. Life could be present in these odd places, and the way life manifests itself might be totally different from what we see here on Earth.

    So yes, CFC is a good sign, but aliens might be much weirder and let's not expect that they follow the same patterns as we do. I mean, aliens don't need hairspray.

  • by gmuslera ( 3436 ) on Tuesday November 27, 2012 @09:26AM (#42104587) Homepage Journal
    If they analyze CFC content in earth atmosphere 30 years ago would conclude that here may still exist life, but that surely isn't intelligent enough.
  • by Moraelin ( 679338 ) on Tuesday November 27, 2012 @09:26AM (#42104595) Journal

    The problem with CFC is that it's duration is an insignificant blip at cosmic scales. We've used it a little, we're phasing it out because it ruins a rather important layer of the atmosphere.

    Our planet will continue to exist for about 5 billion years after the point where we reasonably reached a point that some aliens could contact at all without coming all the way here. (For most of our time on the planet we couldn't receive radio and didn't have telescopes.) Out of that, we've been abusing CFC heavily for maybe 50 years.

    Let's say that t would take a while to get weaned off them, and for the upper atmosphere to gradually clear of them. Like maybe 500 years instead of 50. But it's still 500 years out of 5 billions.

    That's a chance of of 1 in ten millions that if a civilization is there, you'll detect it by CFCs.

  • by ledow ( 319597 ) on Tuesday November 27, 2012 @10:07AM (#42104949) Homepage

    And light pollution measures and energy saving says that the streetlighting we've had for a mere fraction of a galactic second (i.e. a couple of hundred years) won't be here in that same fraction again.

    Hell, as it is, we try to reduce the amount of light that goes somewhere unnecessary (e.g. the sky!) or that is produced and doesn't do anything. There are already countries and cities with lighting that's dynamic based on the cars rolling over it (which means the signal is even HARDER to find, even if you knew what you were looking for).

    And in terms of the stretch of a civilisation, lighting visible even from orbit, let alone the other side of the galaxy, is literally a tiny flicker that you'll only catch if you're constantly listening to EXACTLY that, in EXACTLY the right place for a few billion years.

    Hell, it's hard enough to see all of Earth's artificial lighting from orbit if there is cloud cover, let alone from somewhere like where Voyager currently is, and as you got further out the inverse square law solves the problem nicely to give you a probability of anyone detecting it tending rather swiftly towards zero.

    If you want to detect a civilisation, about the only sensible thing to do is ignore the planets, look at the stars. Because sources of energy that huge, that well light-up, that stable, that predictable and, with suitable technology, even harvestable (I believe it's called a Dyson sphere) are likely to be something that won't stop being a commodity for a long time and activity on them will be inherently visible (even if that's by one-day disappearing entirely).

    Think to yourself. I plonk you down into the universe at an unknown point and at an unknown time since the Big Bang. I give you a billion-year-long-life (sound a lot? It's not). How do you find someone who's had the same done to them? The chances are you're not even going to be able to see each other, would never be at the right stages at the right times to communicate with each other before moving onto the "next most advanced / obvious method of communication", and even if you do by some chance talk be too far away or your communication too "out of date" to do anything useful with it.

    Until you can quite literally bend space and visit other places, it's all a bit pointless to be looking because of simple physical laws. And by the time you *can* do that, it's easier to just plonk a sensor on every star system with your space bending techniques than it would be to ever listen out for them all.

    We are quite literally talking about how to detect a particular mayfly of interest on an entire planet of activity. And by the time we do it, that mayfly has evolved to build its own space program and buggered off deeper into the galaxy anyway.

  • by vlm ( 69642 ) on Tuesday November 27, 2012 @10:28AM (#42105157)

    What makes you think that life on another planet won't have found some biological use for CFCs?

    Oh man, talk to a chemist, they are inert, which makes things biologically complicated and the precursors are beyond nasty. For a good time google for Bromotrifluoromethane Synthesis (aka what you non-chemists would call "Halon") and imagine what it takes to make it both industrially and almost unimaginably via biosynthesis. Its not so much the final step that's the problem, but the precursors, processing the raw materials, etc.

    Its probably a pretty good "dependency" marker indicating advanced stainless steel fabrication, extensive acid production industries, hmm I'd have to think. Biological tissue has severe issues dealing with fluorine ions, which is too bad.

    Its not for lack of evolutionary pressure. Plenty of vessels and orifices would benefit by a native layer of teflon. Imagine the predator prey relations in a world of teflon skin. Some of the room temp liquid CFCs would superficially make a good replacement for that fluid in the bone joints (sorry not doc don't know its technical name).

    Theres also some evolutionary pressure in that you'd need a species that eats flourite ore rocks (or at least stuff grown in its soil, or naturally heavily floridated water) AND in the halon example a biological bromine source... One or the other, OK, but at this time of day I can't think of a way to pull off both. Some kind of migratory coastal ruminant mammal? Um...

    Also there's some thermodynamics issues, if you could pull off the synthesis in a cell, it would need to be a better idea than simply synth more ATP or hemoglobin or whatever else... Need to find a bio app where CFCs are more beneficial than anything else a cell can synth. CFCs are expensive to make so you need a good reason. Much as superficially silicon based brains "seem" more sensible than neuron based brains but its so hard to make a self reproducing factory the size of a typical mammal womb that its not happening any time soon.

    To some extent thats why halon is such a good fire extinguisher around humans. Terrestrial biochemistry has almost no idea how to interact with it, so it pretty much doesn't. CFC suffocation is a zillion times more likely than CFC poisoning. I was told but am too lazy to verify that if you get CFCs into your blood your kidneys get somewhat confused.

  • by vlm ( 69642 ) on Tuesday November 27, 2012 @10:41AM (#42105283)

    .... atmospheric 'fingerprint' (i.e. chemical spectra) is very different from natural elements

    Are these CFCs made from exotic kinds of matter?

    Yes. This is another "talk to a chemist". Ur doing it wrong, when halogens accumulate in your ozone layer. There seems to be no way to get them there, in extreme bulk, other than CFC release on the surface, or maybe some kind of insane doomsday weapon, both of which indicate extreme industrialization and a certain lack of ecological concern.

    A standard /. automotive analogy is car sized lumps of unoxidized iron with certain precise and consistent fractions of dissolved carbon found on top of strips of heavy petroleum fractions mixed with gravel is just too weird geologically and biochemically to be anything but the product of intelligent life. You just don't find those elements laying around in that physical configuration.

  • by Gilmoure ( 18428 ) on Tuesday November 27, 2012 @11:41AM (#42105835) Journal

    Exactly! All this science stuff is just humbug malarkey spread by all e college people who like to flaunt their learning as they drive past in their Suburus. And the only thing worse than an college person are those dirty worker types, all ignorant and stupid and stuff. Nope, the only people you can trust are those that wear nice suits, drive nice shoes, and wear nice cars. the sorta people you find running Wall Street. Their the last, best hope for hoomanity!

  • by Immerman ( 2627577 ) on Tuesday November 27, 2012 @01:08PM (#42106615)

    I know the whole space-station/asteroid colony thing is cool, but planets have several advantages

    1) Your survival is not dependent on the continuous operation of high technology devices - especially important if you're thinking in terms of millenia and insuring your descendants survive even if they pass through some form of knowledge-sapping Dark Ages.
    2) They're big, and virtually indestructible.
    3) Any ecological catastrophe is likely to proceed slowly (see 2), likely giving you decades or centuries of to develop a fix rather than the hours or months likely in an artificially constrained ecosystem.
    4) They're far more suitable as a "genetic heritage" site if you want a large, chaotic system of thriving genetic diversity
    5) Lots of people might well prefer to live within a thriving ecological web than in a rigorously controlled environment. I know I would.
    6) And possibly most importantly, if you have suitable candidates terraforming a planet is probably one of the most cost-effective ways to support billions of individuals. In fact the up-front costs of converting Venus (Mars is a much tougher nut to crack) into something way more hospitable than an asteroid are probably negligible - design a bacterium that will thrive in the current environment and bind atmospheric carbon dioxide into some stable solid, then seed the planet with them and wait a few centuries. Sure it takes a while, but it's a grad-student synthetic biology project with extra credit for having your bacteria designed to die off as conditions approach Earth-norm. Heck, we're almost to the point of being able to do such things ourselves. And once you've got a planet in the proper temperature range with a "non-hostile" atmosphere seeding it with "normal" bacteria to add proper amounts of oxygen and establish a thriving microbial biome in which multicellular life can thrive, while perhaps more challenging, is still potentially a research-project level endeavor whose expense will trivial compared to say, building an interstate highway. So basically, given cheap interplanetary travel all you need is a few individuals with vision to work on a centuries-long project and you can quite possibly terraform an "easy" planet to the point that people could walk unprotected outdoors and establish homesteads, even if they have to import their own multicellular life.

    Meanwhile building a viable enclosed ecosystem even the size of a small city is likely to be an extremely expensive undertaking, especially when you factor in radiation shielding, meteor defense systems, etc. Not to mention gravity - tethering is relatively cheap, but enough cable to support a city (plus shielding) under anything approaching Earth-norm accelerations is still going to be impressive, not to mention you have to perform ongoing maintenance continuously. Perhaps the whole thing could be done organically as some sort of city-sized organism/symbiosis, but that's supposing a much more advanced level of biotechnology, and you'd still have to feed the thing as it grows, though ideally it could absorb sunlight and some convenient carbonaceous asteroids for most of it's needs.

  • by IndustrialComplex ( 975015 ) on Tuesday November 27, 2012 @01:26PM (#42106799)

    It will take over a thousand years to get there, assuming you're a photon (are you?).

    Since I am a photon:

    I am already was there.

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