Let’s Make A Galactic Beacon!

 

I remember when the SETI screen saver first used my computer (over 56k dial-up!) to help to try to detect signals made by another civilisation. We never found anything that I know of, but that won’t stop us from trying to send our own signal!  What would it take to get a message to another galaxy?  This interesting presentation by James Benford on Youtube (paper) has a bunch of thought-provoking ideas.