Space Aliens from Roswell, NM UFO Museum
What happens to Christianity if space aliens from another world were to make contact with us? What would they made of the Garden of Eden, the Incarnation, the Crucifixion and a thousand other details that are part and parcel of Christianity? What are the chances that any of the space aliens would ever convert to Christianity?
In fact, all the major monotheistic religions would come across as quaint and primitive. That includes Judaism and Islam. The life experience of creatures from another world would be so radically different that they in turn would affect how (and whom) earthlings worshiped.
I do not necessarily believe that we will ever contact space aliens, but I do wonder what would be the result of such a contact. At worst, it would be like that famous Twilight Zone episode from Season Three of that show entitled “To Serve Man.” (At the end of the episode, it is revealed that the “To Serve Man” book the aliens carried was not an altruistic guide, but a cookbook!) At best, there is the movie The Day the Earth Stood Still (1951) with Michael Rennie’s Klaatu come to warn Earth that it is in danger of destroying itself.
Myself, I am more inclined to think of any space invaders as Conquistadores come to enslave the planet and mine it for its riches.
tarnmoor 
Because we have invented religion, but not a practical form of space travel, does it necessarily mean that any ‘beings’ that have mastered space travel have got their heads around religion any better than us? Just because we aspire to space travel, and fall short of mastering it, we assume that any ‘beings’ that have mastered it must be far more ‘advanced’ than us. Yet, even on our own planet, there are all sorts of creatures that do stuff so much better than us without even thinking about it, and we still consider them somehow our lessers. Space travel may be a piece of cake for lots of things out there, even though they can’t play football or understand the stock market.
They may be just as stupid as us about the concept of God.
But, more likely, it has never even occurred to them.
That’s quite possible.