[fishtank]

http://www.ourpla.net/cgi-bin/pikie.cgi?FermisParadox

Fermi's Paradox

We are alone.

[PatrickHenry]

Lots of explanations here, some good, some goofy, to account for the "silence:" Fermi paradox (Wikipedia).

[RadioAstronomer]

Too many variables to validate "Fermi's Paradox.

Distance is one of the bigs. If a race is radiating into space and they are further away from us in light years than the number of years they have been radiating, we will never see them.