I understand that Catholics usually believe in evolution, but how could they square away the fact the vast majority of all life could exist without knowing salvation via Christ? Being ignorant of Christ doesn't automatically mean you are damned, but this now means belief in Christ is optional and kind of just a localized thing some humans choose to do.
It really should effect you, if for example aliens claimed their savior was the "real" messiah, how could you dismiss that?
I get that these are just dogmatic questions that arise everytime two religions become aware of each other, but it metaphysically pretty difficult too, like events the Rapture essentially cease to make sense or will have to be radically re-imagined. Questions about whether biblical commands apply to ET life are going to be difficult as well, let alone missionary work.
Upon reflection ET life isn't necessarily bad for the logical consistency of religion as I initially thought, but is more organizationally difficult.