Re: Earth (spoilers probably)
If BSG is in a different universe, it doesn't matter what Earth is.
Every show and film and book ever created takes place in a different universe. This is the same. BSG's universe isn't somehow "more different" just because of what Earth might look like.
If not, then how do they explain humans actually evolved on Earth? That would make the Earth in BSG very very far into the future.
So? Then that's what it is.
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