Actually, about a year (or more) ago the Vatican DID take a position regarding belief in extra-terrestrial life.
Summarized they said it did NOT create a problem doctrine-wise for Catholics to believe in the possibility of other sentient life forms in our universe. That if they did indeed exist, they were created by the same God that created all of us.
Thanks for your input, and so noted. I meant the Church has not taken a position claiming the existence of aliens, but fair enough.