In the new film "Project Hail Mary", humanity sends an interstellar ship to another star system — Tau Ceti — in a last-ditch effort to save Earth from an alien threat. As it turns out, the key to rescuing our planet is a microbe that evolved on a world orbiting this star.
But how likely is it that the Tau Ceti system actually harbors alien organisms? And out of the thousands of planets discovered in other solar systems, how do researchers determine where to look for life?
