What Can Catholic Theology Say About Extraterrestrials?

As Arthur Clarke (IIRC) once wrote that Catholicism and Christianity carried an internal time-bomb in the words "God made Man in His own image".

The questions then being "Did God make Aliens in His own image also? What if they are completely different from us? Which Image of God is the correct one? Did God send Jesus down to save the Aliens also? Did the Aliens require 'saving', or were they sinless? If they were sinless can we say that the Aliens are more worthy than us?"

The different between an Atheist and a <member of the religion of your choice> is that the Atheist disbelieves in only one more god that the <member of the religion of your choice>. So a Catholic might disbelieve in 381 'pagan' gods, but if he becomes an Atheist he now disbelieves in 382 non-existent gods.