[nbush]

Anyone remotely interested in this idea should check out Stanislaw Lem's His Master's Voice [1], which is an entire (short) novel about how and why an extraterrestrial message would be encrypted. It's worth mentioning how why turns out to be the most compelling question.

1. https://en.m.wikipedia.org/wiki/His_Master%27s_Voice_(novel)

[sn41]

A brilliant book which made me think that this is how science is really done. One of the questions is whether there is a message at all. How this message is first suspected (due to non-pseudorandom behaviour of a fraudulent table of random numbers) itself is a fresh idea. I found the various hypotheses in this book itself to be a very nice. IIRC, there is also an "opera singer" hypothesis that it is not the content of the message which matters, but its frequency.