A very fun little game! I quite liked the art style (it gives me similar vibes to late 2000s early 2010s flash games). Audio design is simple and effective. I did encounter a bug where selecting the static defender just broke the game rather than placing down a new permanent defender. Additionally, it would be nice if there was a round timer or 'asteroids remaining' counter so I know when the round is close to ending. An overall strong submission though!
Edit: Tried again after reading another comment and it was just my own incompetence - didn't realise I had to replace one of the other active abilities! Oops! It does raise a similar point they made - a lot of the other active abilities you start with are just outright worse than ones you can get, which pushes people to get passive ones instead.