Looking for alien lasers, not radios

New Scientist Space ^ | 04/15/06

[rattrap]

Are WE sending out such signals?

Only most all of the over the air signals that have been ever been broadcast. We've been doing it for a miniscule amount of time though on a universal scale.

For example Reginald Fessenden's signal that was broadcast on Christmas eve 1906 has only just now made it 100 light years away (if it made it out of the atmosphere).

[Ronin]

I know that a lot of the signals we have sent out are Theoretically still spreading and could possibly be picked up by an alien civilization, but I am a little dubious that any of those signals are going to be coherently "visible" even to radiotelescopy over more than a handful of light years.

That wasn't really my question. There's a big difference between that and a searchlight type beam of coherent radio signals -- which is what I think we are looking for.

[PeoplesRepublicOfWashington]

Come on--give us all the information we need to solve this story problem! Everyone knows it depends on whether the radio signal was sent via AM or FM, and what the color of the laser beam is.

[Chode]

can't make tooo easy... 8^)