Here are the things I did for the last week:
1. Found textures for Earth, Moon, Earth’s clouds and some others
2. Made notes (on paper :)) about gameplay, menu, game science and logic.
3. Took part of the core files from RiU, like input, audio, timers, etc. and started to add first classes to the new game.
4. Played a bit with Away3D and decided to use Away3DLite, which is smaller and works faster. (Good tutorials about Away3D are here.)
This is it. I hope to have something visual next week.