I came across this story in the UK Sunday Herald about the relation of religion, especially Christianity, to the possibility of extraterrestrial, or even extra-dimensional, life. This is something we don't really think about because we are so used to aliens in movies & TV. If people found out there were really aliens, though, it would be crazy.
“Is original sin something that affected all intelligent beings?” he asks. “Is there a sort of ‘cosmic’ Adam predating even life on Earth? Is Jesus Christ’s redemptive sacrifice sufficient for the whole universe? Would there be a parallel history of salvation on other planets?”
I think people would definitely freak out if it was known that some sort of beings existed and even observing mankind. The idea, though, that alien life was the basis for religion and myths would make people just as bonkers!