Okay, this is in fact a bunch of related sub-questions, but I'll try and sum them up in one:
How has the physical workings of the Moon -- home to the new central hub of humanity: Luna -- changed in the world of Mutant Chronicles compared to what we have in real life?
How long is a day in Luna?
What's up with gravity?
How does the atmosphere work?
If these resemble Earth IRL, how has humanity achieved that? With what technology? (And hasn't that tech become corrupted by the Dark Symmetry?)
Water? Where does the water (and proper quantity of it) come from?
The core book, as far as I can remember (don't have it on me atm), strongly implies that life in Luna (the greatest city of humanity, located on the Moon) is quite similar to what we have (I mean had, in the noirish 1940s-1950s, to be more precise) on Earth. Days with 24 hours, Earth-like gravity and atmosphere, etc. But real life physics don't really allow that... at all. So, the Moon must have been brutally terra-formed.
Are there official sources on this? Where? If not, are there quality fan explanations? Or do you have a plausible (in game plausible, that is) theory?