That's no moon! The crescent moon has lights shining in the shadow part of it!
OK, so, either it's a moon that's only crescent shaped and nothing else... Or there's something that illuminates the surface on that moon.
But since one moon is full and the other crescent, I'd sooner believe it being a fake moon, since it'd be strange for one moon to be full while the other is only partial, unless the second moon is actually reflecting enough light off the planet to illuminate the first moon...