[meteorite-list] seti

[Jonathan Gore]

Neil Caliva wrote:
> How far could our EM signals generated by humans be detected?

This was answered in the Q&A of the May/June 2005 issue of the 
"Planetary Report"; it says military EM signals could be detected out to 
about 50 light-years if the aliens used a dish the size the of the dish 
at Arecibo and most signals (like TV signals) could be detected out to 1 
light-year or less with antennas similar in size to ours. However, an 
astrophysicist told me that we could be detected out to a few hundred 
light-years if we tried "really hard". But if the source signal is 
directional (most of the EM signals that travel furthest are) wouldn't 
that cause more complications? -- Since you would have to match the 
direction of the EM signal.

Jonathan