This seemed like a fun concept, even if you weren't able to accomplish everything you had planned.

I found that with the current behaviour/balancing, I really wasn't able to hold off the asteroids for long before they swamped my planet enough to prevent me from moving. Since the cannon shots didn't destroy the asteroids and lingered in the playspace, they themselves would end up contributing to the clutter

Your game's binary didn't have executable permissions set, so I need to mark you down on Linux compatibility.

Always nice to see a project with sources available. I notice that commit 88ad6f0 mentions fixing damage. I'd love to play an updated build!

Don't forget to make your game public before the submission deadline ^_^