We transmitted several messages to the space and listening to space for signs of intelligent life for years (SETI).
Assuming they have at least the same technology we have, could they detect these messages we sent out?
If not, how powerful transmitter is needed to make our word heard, let's say, from 1000 light years? Which wavelength we should use to transmit?
ps: Apparently not so many ET related questions on this site, maybe I asked on the wrong site?