In summary, based on data from searches for radio signals, it is probably safe to say that the likelihood of another civilization with technology similar to our own existing within 10 light years, 100 light years, or 1000 light years of Earth is very small. However, this does not mean that such a civilization cannot exist, only that the odds are low.
I think it fair to say Earth has enjoyed fortuitous circumstances, but, given a jillion galaxies out there, each with hundreds of billions of stars, I am not convinced it is unique.
#38
dodo
697
2
I have one question: how is it that a transmitter with a wider bandwidth gets a poorer reception from a distance? In the link quoted earlier,
I can't really see, to begin with, where the "Bt" (transmitter bandwidth) is used in the formula for the reception range.
P.S.: I think the idea is that the "Br" (receiver bandwidth) has to be at least as wide as the "Bt"; and that noise depends on this receiver's bandwidth. But I didn't quite understand (being a layman in physics) this "Nyquist noise" equation; maybe someone can provide a link, more related to antennas than the Wikipedia page.
Last edited:
#39
dodo
697
2
For what is worth, there is an interesting initiative here: