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SO… I usually write fantasy, but I decided to try science fiction. (It wasn’t a completely random decision, I read a lot of it and actually, know a lot about it) I’m working on a story set in the future, 2999 at the turn of the century. England moved to Mars beginning in 2125 and finalizing it in 2130, then becoming Martania. My only problem is with how to include Christianity. I know that it would change over the years- just little things like how they celebrate Christmas etc. But how do I make that seem believable? Any ideas? (and please share any tips for worldbuilding a science fiction world!)