Oh, Constance Demby is a total babe. This woman must have fallen from heaven. She is so totally inspired. Novus Magnificat is grand, but the most amazing work of hers, imho, is Aeterna. If you have NOT heard Aeterna, and you like neoclassical new age type music, you really must hear it.
As for space music in general, Jonn Serrie is another must-have. Planetary Chronicles I and II are just mind-blowing tours of space. Then, if you want to go into some darker ambient, you should check out Gustaf Hildebrand.

When do we eat?