You forgot to mention that "Space" is the shoot key.
The game is very well done, especially the Physics. When a rock colides with each other is impressive.
The only problem for me is that the Ship model is very similar to the Rocks.
I'm curious to see your next game, this time with a original concept.
I would love if you could play my game and give me some feedback too, it's called "Touch of Madness":