Now that we know planets are common in our galaxy, how can we tell if one holds life? Sure, it will take incredibly powerful telescopes and ambitious new space missions, but what are we looking for? Life on Earth has an expiration date. No matter what humans do, our aging sun will eventually be so hot that we can't survive. If we want to live on, it will have to be beyond Earth. The only question is, will it be us who live on, or just our radio broadcasts and dead satellites?