Hello! I'm brand new to halfbakery and this is my first posting so go easy on me ;)
So what's the deal with SETI?
SETI is searching for -radio- signals hoping to randomly come across a signal from "out there". Many scientists have noted that any advanced civilization will have moved beyond
radio or will at least be using so much compression and channel hopping as to sound and look like static to us. In a similar vein, any civilization not as advanced as us obviously won't be transmitting.
But what is the one thing common to -solar- systems? A Sun! Even the earliest civilizations on Earth recognized the sun as a powerful symbol. And what can you see from anywhere in the galaxy? Other suns!
So finally here's the idea. There is a product, I think it's called a Transflective Optical Display but I may be mistaken, that can either be transparent or opaque depending on an electric charge. There was a virtual reality product several years ago that used such a material and rich people use it like window blinds in large panels of glass.
This is where it gets fun. I believe that robots could build and assemble an massive array of these panels and cover at least half of the sun with it. By cover I don't mean right on top of it of course. Far enough away to avoid any damaging heat, but as close as possible so as to require as little material as possible (although the amount of material this requires probably involves mining asteroids). Think of half a Dyson sphere that can make itself opaque or transparent on request. The array would be solar powered by panels on the inside of the array.
If we wish to contact or be contacted by another race I believe this to be the most sure fire way to attract attention. Could you imagine looking up at the sky at night and seeing a star that's been there as long as you can remember one day suddenly blink out? And then on and then off and then on? You would surely then point any receivers and observatories you might have (antennas, satellites, whatever) directly at such a strange thing if you couldn't just go visit it in person.
Now, if we decide that what we want is to NOT be found there's no reason (since we could build the thing in the first place) we couldn't extend the spherical array out to encompass the sun and the earth completely thus concealing our solar system and our planet. In this case we would need to adapt the array to supress the x-rays being generated for maximum effectiveness.
But why only cover half of it for communication or attention? Because some sunlight has to reach the earth. We could cover more than half and still do that but we couldn't cover it all. The array would need to be synchronized with earth's orbit to rotate and always be on the opposite side of the sun.
Such a large project would definitely take a huge amount of time to complete (hundred years maybe?).
That's why I propose creating a fleet of robitc workers that would handle the entire operation. Mining, manufacturing, assembly (each other and the structure), etc.
The array would be effective even at a quarter it's completed size so we could start using it before it's complete. The array could even pipe extra solar power back to earth or other stations.
Communication would be far from instantaneous because it will take the light we block a Very Long Time to reach other solar systems but we have to start somewhere. But maybe all we need is to attract some attention.
If Transflective Optics are to complex to manufacture in space or require to much exotic material maybe there is a device that could block or generate huge amounts of X-Rays?
More details on the structure of the array:
The panels would be hexogonal and connected by a lattice that would distribute power, house solar collectors, and vent heat. The lattice would also allow robotic workers to be brought over it to any point on the array for maintenance or repair.