4 ms·

Search for ET intelligence extends to near-infrared optical signals

18 points by tanglesome 12y ago

drzaiusapelord 12y ago
SETI is falling for its own kind of "god of the gaps." Oh, no aliens in this radio spectrum? How about that? How about analyzing it differently. How about we do the analysis on a bunch of desktops via a screensaver? Now near IR? SETI comes off as such a useless endeavor, especially when you consider we couldn't even detect a civilization like ours. We'd need something like a planet sized antenna to pick up stray signals from even a trivial distance, by space terms. Thankfully, its cheap and doesn't divert from worthy pursuits, but I wish geeks were more interested in things like a radio telescope on the far side of the moon, something that is almost never publicized or fanboyed, than OMG ALIENZ!
- duaneb 12y ago
  > SETI comes off as such a useless endeavor, especially when you consider we couldn't even detect a civilization like ours. This is easy to say BECAUSE of SETI. Data supporting the null hypothesis is still useful.
  - api 12y ago
    It's easy to say because radiation diminishes with the square of distance. Someone would have to be blasting out a ton of RF in our direction for us to notice. I'm talking about gigawatts at a minimum, probably more like terawatts. Who's going to blast thousands of gigawatts of RF into the cosmos without knowing if anyone is ever going to hear it? Then you have the question of whether or not this would be a good idea. Four words: relativistic kinetic impact weapon. There would be no rational reason to do such a thing, but given what we know of our own species we cannot assume rational motives for others. Intelligence seems to occur in predators more than prey here on Earth, which also means it tends to be coincident with aggressive and territorial behaviors. An intelligence might decide to annihilate you because you are clearly an offense against their God (territorial instincts turned into metaphysics, something humans do a lot). It's likely that another intelligence might reach similar conclusions and lay off the horn. Combine the cost, lack of benefit, and possible danger, and mega-transmissions that SETI might detect are just not that likely. The only SETI I can see being successful are efforts to passively detect large-scale artifacts of life or intelligence. These include telescopes capable of detecting biosphere signatures (e.g. lots of free oxygen and water), detection of hypothetical mega-engineering projects like Dyson swarms or the (physically unavoidable) IR and EM emissions of a relativistic interstellar spacecraft, etc. Either that or finding evidence within our own solar system of current or past visitation, which is absolutely not something we can rule out. We've really barely been anywhere, and there are many bodies such as moons or asteroids where any such evidence might be preserved over geologic time scales. A visit a billion years ago might still leave evidence on a waterless, airless body, especially one far from the Sun. A visitor might also have left things that are intended to be found -- it's a popular sci-fi plot but also can't be ruled out and is more likely to actually be found than a signal over SETI distances. Side question: how big would an optical/infrared scope need to be to actually see an extrasolar Earth-sized planet? I'm guessing very big (or a large array of them), but the payoff would be huge. Not only could we see the effects of intelligence, but we could also detect non-intelligent life in general this way.
    - Houshalter 12y ago
      >There would be no rational reason to do such a thing Have more imagination. We, as another intelligence species, could eventually evolve into a threat or competition for resources. Such an ancient civilization probably has long term plans for outlasting through the heat death of the universe and beyond, they have a huge incentive to eliminate others. They might also have weird forms of morality and values so alien to us, we can't even speculate about it. They might come to earth to enforce their weird values on us, or just wipe us out and not deal with it. Then there is Paperclip Maximizers: http://wiki.lesswrong.com/wiki/Paperclip_maximizer http://wiki.lesswrong.com/wiki/Paperclip_maximizer Many people believe that most civilizations are eventually overtaken by AIs which are likely programmed with simple utility functions. E.g. and AI programmed with self preservation will make as many redundant copies of itself, store as much mass and energy to preserve through the heat death of the universe, destroy anything that has even a tiny probability of being a threat to it, etc. And you don't need relativistic weapons. A single self replicating nanobot would probably be sufficient. They don't need to go to any effort, if there is a tiny advantage to killing us then we are screwed. The universe is a terrifying place and it's quite possible the only reason we are alive is anthropic bias. Just by chance we happen to be far enough away from other civilizations to evolve to the state we are now. But at any moment another intelligence could expand into our space and wipe us out in the blink of an eye.
      - api 12y ago
        That's basically the sort of thing I was getting at: that motives are by no means straightforwardly rational among humans, let alone aliens. Your point about extremely long-sighted competition is interesting though, and might be a rational motive if the universe were seen as fundamentally zero-sum. On anthropic bias: look up how many times we almost had a nuclear war. Makes me wonder about quantum immortality. Maybe we're just in the universe where we didn't incinerate ourselves. https://en.wikipedia.org/wiki/Quantum_suicide_and_immortality https://en.wikipedia.org/wiki/Quantum_suicide_and_immortalit...
  - drzaiusapelord 12y ago
    Inverse sq law tells us the same thing for free.
- blacksmith_tb 12y ago
  I am having a hard time imagining a screensaver-based radio telescope on the dark side of the moon. SETI is a quixotic project, but that doesn't mean it has no value. It could well inspire geeky kids who go on to work for NASA or ESA etc. on space telescopes.
deckofcrap 12y ago
They already use genderless no form-factors. Its an option available to everyone & more.

18 points by tanglesome 12y ago

SETI is falling for its own kind of "god of the gaps." Oh, no aliens in this radio spectrum? How about that? How about analyzing it differently. How about we do the analysis on a bunch of desktops via a screensaver? Now near IR? SETI comes off as such a useless endeavor, especially when you consider we couldn't even detect a civilization like ours. We'd need something like a planet sized antenna to pick up stray signals from even a trivial distance, by space terms. Thankfully, its cheap and doesn't divert from worthy pursuits, but I wish geeks were more interested in things like a radio telescope on the far side of the moon, something that is almost never publicized or fanboyed, than OMG ALIENZ!

duaneb 12y ago
> SETI comes off as such a useless endeavor, especially when you consider we couldn't even detect a civilization like ours. This is easy to say BECAUSE of SETI. Data supporting the null hypothesis is still useful.
- api 12y ago
  It's easy to say because radiation diminishes with the square of distance. Someone would have to be blasting out a ton of RF in our direction for us to notice. I'm talking about gigawatts at a minimum, probably more like terawatts. Who's going to blast thousands of gigawatts of RF into the cosmos without knowing if anyone is ever going to hear it? Then you have the question of whether or not this would be a good idea. Four words: relativistic kinetic impact weapon. There would be no rational reason to do such a thing, but given what we know of our own species we cannot assume rational motives for others. Intelligence seems to occur in predators more than prey here on Earth, which also means it tends to be coincident with aggressive and territorial behaviors. An intelligence might decide to annihilate you because you are clearly an offense against their God (territorial instincts turned into metaphysics, something humans do a lot). It's likely that another intelligence might reach similar conclusions and lay off the horn. Combine the cost, lack of benefit, and possible danger, and mega-transmissions that SETI might detect are just not that likely. The only SETI I can see being successful are efforts to passively detect large-scale artifacts of life or intelligence. These include telescopes capable of detecting biosphere signatures (e.g. lots of free oxygen and water), detection of hypothetical mega-engineering projects like Dyson swarms or the (physically unavoidable) IR and EM emissions of a relativistic interstellar spacecraft, etc. Either that or finding evidence within our own solar system of current or past visitation, which is absolutely not something we can rule out. We've really barely been anywhere, and there are many bodies such as moons or asteroids where any such evidence might be preserved over geologic time scales. A visit a billion years ago might still leave evidence on a waterless, airless body, especially one far from the Sun. A visitor might also have left things that are intended to be found -- it's a popular sci-fi plot but also can't be ruled out and is more likely to actually be found than a signal over SETI distances. Side question: how big would an optical/infrared scope need to be to actually see an extrasolar Earth-sized planet? I'm guessing very big (or a large array of them), but the payoff would be huge. Not only could we see the effects of intelligence, but we could also detect non-intelligent life in general this way.
  - Houshalter 12y ago
    >There would be no rational reason to do such a thing Have more imagination. We, as another intelligence species, could eventually evolve into a threat or competition for resources. Such an ancient civilization probably has long term plans for outlasting through the heat death of the universe and beyond, they have a huge incentive to eliminate others. They might also have weird forms of morality and values so alien to us, we can't even speculate about it. They might come to earth to enforce their weird values on us, or just wipe us out and not deal with it. Then there is Paperclip Maximizers: http://wiki.lesswrong.com/wiki/Paperclip_maximizer http://wiki.lesswrong.com/wiki/Paperclip_maximizer Many people believe that most civilizations are eventually overtaken by AIs which are likely programmed with simple utility functions. E.g. and AI programmed with self preservation will make as many redundant copies of itself, store as much mass and energy to preserve through the heat death of the universe, destroy anything that has even a tiny probability of being a threat to it, etc. And you don't need relativistic weapons. A single self replicating nanobot would probably be sufficient. They don't need to go to any effort, if there is a tiny advantage to killing us then we are screwed. The universe is a terrifying place and it's quite possible the only reason we are alive is anthropic bias. Just by chance we happen to be far enough away from other civilizations to evolve to the state we are now. But at any moment another intelligence could expand into our space and wipe us out in the blink of an eye.
    - api 12y ago
      That's basically the sort of thing I was getting at: that motives are by no means straightforwardly rational among humans, let alone aliens. Your point about extremely long-sighted competition is interesting though, and might be a rational motive if the universe were seen as fundamentally zero-sum. On anthropic bias: look up how many times we almost had a nuclear war. Makes me wonder about quantum immortality. Maybe we're just in the universe where we didn't incinerate ourselves. https://en.wikipedia.org/wiki/Quantum_suicide_and_immortality https://en.wikipedia.org/wiki/Quantum_suicide_and_immortalit...
- drzaiusapelord 12y ago
  Inverse sq law tells us the same thing for free.
blacksmith_tb 12y ago
I am having a hard time imagining a screensaver-based radio telescope on the dark side of the moon. SETI is a quixotic project, but that doesn't mean it has no value. It could well inspire geeky kids who go on to work for NASA or ESA etc. on space telescopes.

deckofcrap 12y ago

They already use genderless no form-factors. Its an option available to everyone & more.