That's one of the main problems with religions. Always overstating the importance of certain things. For instance, while we live in an amazingly vast universe of billions of galaxies, each containing billions (and sometimes trillions) of stars, there are still those who believe the most important thing in all of existence was some carpenter thought to have lived on Earth around 2000 years ago.
It's going to be really really awkward for them when we do discover some form of life in the universe. Even if it was only a single cell, it would still imply that humans aren't alone in the universe and that there's a chance that God (if he/she/it exists) has his attention focused on a much superior species living somewhere out in the universe. It would really kill the Pope's authority.