Can we construct something so we can use the sun as a signaling device?

Discussion in 'Architecture & Engineering' started by cosmictotem, Apr 4, 2015.

  1. cosmictotem Registered Senior Member

    Messages:
    747
    I was just reading about the fast radio bursts scientists are watching to determine their origin. It got me thinking about what ways we might come up with to signal our presence to an intelligent extraterrestrial species.

    It suddenly occurred to me that our own sun is a giant signaling device, basically a lighthouse. Our own scientists monitor the interplay of distant stars and their planets to get a sense of where habitable planets might be.

    What if we could build something large or powerful enough that could orbit the sun (or remain stable on one side of the sun) and manipulate or alter any sunlight that passes through it to produce an amplified and/or recognizable signal to a distant alien species with radio technology that another intelligent species (us) is creating it that signal?

    Could a ring of densely packed laser beams forming a large lens for sunlight to pass through produce any detectible effect? In other words, turning the lasers on and off at assigned intervals to produce a message? (The benefit of deploying this device (or any other device for signaling we can think of) close to the sun is we can use the sun's immense energy to power it. )

    If lasers wouldn't work, is there anything that would which we can build now or in the near future?
     
    Last edited: Apr 4, 2015
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. cosmictraveler Be kind to yourself always. Valued Senior Member

    Messages:
    33,264
    A laser is a very small point of light. If you do not know where to point that point of light you won't communicate with anyone. That point of light would also have to reach a civilization which has the ability to understand what those bursts of light actually mean other than a random flashing on and off. So there are problems with any types of communications lasers or radio waves for we do not know where they will end up. Every type of communication that Earth has received has been shown to be a naturally occurring phenomenon so far. As this new signal will be found to be coming from some type of star, gamma burst or other cosmic event in the long run.
     
    cosmictotem likes this.
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Dr_Toad It's green! Valued Senior Member

    Messages:
    1,830
    Y'all read up on Kardashev civilization types. We'd have to be a type II to control our sun's output in any significant way, and this sort of 'signal mirror' strikes me as that sort of thing.

    And we aren't even civilized yet.

    Please Register or Log in to view the hidden image!

     
    cosmictotem likes this.
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. cosmictotem Registered Senior Member

    Messages:
    747
    Well, the laser array wouldn't be sending a signal of laser light. I'm suggesting that a ring of laser beams be used to interrupt and/or filter the sun's light. The intelligently modified sunlight would be the signal itself. As we know, small interruptions in starlight from distant stars are indications of orbiting planets around those stars. In those cases it is natural interruptions. In the same sense, I am asking if we could artificially block or dim our star's light on its way out into distant space as a signal that an intelligent species is manipulating or artificially filtering its star's light?

    So to recap, the laser array would not be sending the signal. It would only be meant to disrupt our sun's "signal" (which presumedly can already be seen from distant planets) in such a way to indicate an intelligent species is manipulating its star's light.

    As for which direction, it wouldn't matter. This device would simply orbit the sun and send a repeating pattern of messages in all directions, until we detect a reply or suspect a more promising area of space. Then it could be remotely directed to that more specific target, as needed.
     
    Last edited: Apr 5, 2015
  8. cosmictotem Registered Senior Member

    Messages:
    747
    Well, I'm not suggesting we need to harness all or any of our sun's energy. I'm suggesting we try to interrupt its outgoing light with lasers before it travels outward towards the rest of the galaxy. We might be able to use some of the sun's energy to power the lasers but I'm not saying it's required. The laser array would not fire its beams into distant space, it would only fire in a concentric pattern that would create a "lens" through which sunlight would have to pass through and which would generate an alternating on/off pattern to form a message, which would travel out to the distant parts of our galaxy.
     
  9. AlexG Like nailing Jello to a tree Valued Senior Member

    Messages:
    4,304
    Light does not interfere with itself. A laser would have no effect on sunlight.
     
    cosmictotem likes this.
  10. cosmictotem Registered Senior Member

    Messages:
    747
    Assuming lasers are out as an option, what are other possible ways (if any) can we manipulate the sun's light and/or energy to produce an output signal that could be detected across the galaxy?

    Are we just too puny compared to our sun that anything we would have to construct would take more resources than the earth even holds? Obviously, from our vantage point and technology, it is difficult to detect a planet size disturbance in a distant star's output, so it makes sense that anything we do would have to have a planet size impact. Am I asking for the impossible?

    What about, instead of lasers, a ring of "engines" in parallel orbit around the sun that capture the sun's radiated energy and spit it out as a negative image that shutters the sun's light to create an artificial signal? Could it only be a ring or would we have to build a full "screen" of giant proportions with each engine serving as a pixel on the screen?

    Or, is there anyway we can project a planet size shadow or image on the outward face of the sun, thus using the sun's surface itself as a large screen?

    Lastly, would we need a sizable quantity of dust to "dye" the sun a different color? Or could we inject some kind of element or compound that would spread and multiple through some subatomic reaction with the sun? Something that we could inject onto the sun's surface in enough of a quantity that it would alter the color of sunlight enough to be detected across the galaxy? Wait, wouldn't changing the color of light emitted from the sun to the wrong color have serious negative effects on earth?
     
  11. GeoffP Caput gerat lupinum Valued Senior Member

    Messages:
    22,087
    I think you'd need enormous power to produce some kind of spectrum change in the sun that could be picked up by interstellar telescopes. I have no idea the kind of conversion capacity you'd need for that but it sounds daunting. Still, I'm no physicist.
     
    cosmictotem likes this.
  12. cosmictotem Registered Senior Member

    Messages:
    747
    Well, I've been thinking about this and I'm beginning to conclude that perhaps the solution need not be so sophisticated, as my past suggestions have posited.

    All we want to do is periodically disrupt the sun's light on a large scale, right?

    Well, why not just a large but simple "erector set"? A skeletonized screen with millions to billions of cheap hexagonal metal plates that can be independently shuttered on and off (each rotated on a axial) by little accompanying motors all tied into a battery array charged by sunlight through solar panels? The hexagonal plates would act as the pixels of the screen and turn on or off dependent upon whether they were turned parallel or perpendicular to the sun. Because this erector set is so light and cheap, it could be assemble over time with limited or even throw away scrap resources, possibly even undesirable resources on earth. All these plates need to do is be assembled in sufficient size to mimic a planet blocking sunlight. They could even be a polished metal that can reflect light in case we want to put this device to another use.

    We could assemble this device near to earth and test it before we move it into a more suitable position, then operate it remotely.

    As for reservations of whether we can manage the scale of the construction, do you remember "Hand Across America"? Enough people participated that a single continuous line across the continental United States could have been formed in one day. The only thing that stopped them was the line would have meandered through areas too far and not very inhabitable to people, so there were breaks in the chain. But the point was made.

    Ask yourself how many sheets of metal sheathing have been produced in China and world-wide for the construction industry?
     
    Last edited: Apr 5, 2015
  13. GeoffP Caput gerat lupinum Valued Senior Member

    Messages:
    22,087
    Ahh I see. That sounds reasonable, I think: you could place it in the focal path of whatever solar system you were trying to contact. But it would have to be a lot closer to them or just freaking massive beyond any conception of massive presently. Or... Earth-sized, maybe? Physicists claim they can see planets in distant solar systems; I don't know if that's true or how true it is, or if it is just what kind of disruption in signal strength would be required to detect it based on a system we might employ. How big is big enough to see an electrowave blip?

    Speaking as a statistician, would this approach be significantly better than not building it and assuming that other intelligences searching the heavens are using a system that can see us anyway? Or where would they be, in comparison to us, and when? How long will they be looking for? I hate to sound negative, but I guess I also have to ask: if they can see us, what then? If they can't get here, it wouldn't be in aid of much, and we'd never know for a hundred thousand years on average if they had, so the set would have to be in operation at least that long and hundreds of millions of years after.

    Or, maybe, we'd hit on that one civilisation that can both read the signal and get here, or are passing by at close right angles to our system and the device. I'd suggest the 'Greys', but apparently they already know we're here and have seen our bums. Beyond that, I don't know what more interest they could possibly have. (cf. Kingsmen: The Secret Service).
     
  14. cosmictotem Registered Senior Member

    Messages:
    747
    Scientists can indeed detect the presence of planets around distant stars by their disruption of the light coming from those stars. The bigger the planet, the larger the disruption and the easier it is to detect. It is more difficult for scientist to detect the presence of a near earth size planet but they have done it before. My guess is we would have to build something earth size in profile, at the very least.

    I'm not sure how to convert an annual 1538 million metric tons of steel production world wide in to a size metric for determining if we can build it. But based on our annual production figures of dry wall it looks like we are way below the kind of production levels that would enable us to have the excess resources to throw into building such a signal device. But I'm no scientist either. I could be way wrong.

    The only other possible option is if we built it of material nobody on earth wants and we just want to get rid of it.
     
    Last edited: Apr 5, 2015
  15. GeoffP Caput gerat lupinum Valued Senior Member

    Messages:
    22,087
    How about honour? Nobody on earth wants that.
     
    cosmictotem likes this.
  16. cosmictotem Registered Senior Member

    Messages:
    747
    Or poo. We've got plenty of that.

    Please Register or Log in to view the hidden image!

     
  17. billvon Valued Senior Member

    Messages:
    12,757
    Probably the easiest would be an orbiting array of mirrors to periodically block sunlight in one direction. You could modulate the signal by adjusting the size of the mirrors. (For example it would be easy to send an SOS or series of primes with alternating mirrors and open spaces.) Niven uses this idea in his book Ringworld; he calls them "shadow squares." (different purpose, same idea.)
     
    cosmictotem likes this.
  18. cosmictraveler Be kind to yourself always. Valued Senior Member

    Messages:
    33,264
    Again I say that you are guessing that another civilization somewhere will actually see this "blinking" and realize it is made from an advanced civilization somewhere. I don't understand how a laser or lasers can block the sunlight to begin with. Then I don't think that a alien race is looking for "blinking" across the cosmos.
     
  19. cosmictotem Registered Senior Member

    Messages:
    747
    Like an erector set of individually adjustable plates? I agree, as in my subsequent posts after initially posting this thread reveal. However, I've come to the conclusion this array would have to be planetary size in profile to work.
     
  20. billvon Valued Senior Member

    Messages:
    12,757
    Not quite. Nothing moves on this; it's just a solid ring that orbits the sun. Its rotation periodically blocks and passes light, so no motors or movable parts required.
     
  21. cosmictotem Registered Senior Member

    Messages:
    747
    Well, of course, there's no guarantee someone out there is looking out for a signal. But given the Drake equation, why not at least get a working smoke signal set up?

    As for the lasers, I wasn't sure they would be effective either but, to me, since we're dealing with a visual signal a laser beam lens to filter sunlight through seemed a lot easier and cost effective to construct than an actual physical lens. We can span the large distances for which we need to cover a enough large portion of the sun with a fan of laser beams easier than an erector set of physical plates.
     
  22. cosmictotem Registered Senior Member

    Messages:
    747
    Okay. I see. However, you have the same problem as I. These rings would have to have profiles the size of planets.
     
  23. billvon Valued Senior Member

    Messages:
    12,757
    Definitely. They would be neither cheap nor easy - but at least once built they would keep signaling forever.
     

Share This Page