Really well-made game, I love the presentation of it (the audio certainly help me with my anger control after 20 overshooting the little astronaut)!
I think I would prefer the camera switch to the asteroid when you land on then to get more view on top, but it's fun exploring the level too! (speaking of space exploration)
Found a bug at level 4, the little blue/cyan/green astronaut jump out of view when I press the space key. Tried restarting the game, but the bug is still there.
Btw, maybe I just suck, but the boss level felt way too hard, hahaha.