By comparison, our sun is very bright, and, given the distances involved, very close, and planetary light sources are dim enough to fit within the natural variability of light emissions by their parent star.
The advantage of looking for radio signals is that their modulation helps them stand out from background noise.
The down side is, the shell of our radio transmissions is only about 80 or so light years in diameter, and there isn't all that much in such a tiny section of space, though I do keep my fingers crossed for Gliese 581.
Nice pic, but I disagree with your conclusion.
ReplyDeleteBy comparison, our sun is very bright, and, given the distances involved, very close, and planetary light sources are dim enough to fit within the natural variability of light emissions by their parent star.
The advantage of looking for radio signals is that their modulation helps them stand out from background noise.
The down side is, the shell of our radio transmissions is only about 80 or so light years in diameter, and there isn't all that much in such a tiny section of space, though I do keep my fingers crossed for Gliese 581.