Art is great but the audio design is actually incredible, it was very fun listen to the track. All the sfx (which was indeed a little loud) also fits very well with the music too.
Pretty interesting take on the theme, but honestly I feel like it was a bit tacked on to fit the theme rather than a focus of the game. I mean, it's about celestial bodies, but you pretty move like a normal top down shooter, except for the bit that there are planets, which are upgrades that orbits around you. I thought the mechanics of being able to shoot your upgrade away is a bit weird as well. I feel like I never really want to do that, I just do it on accident when I try aiming at the enemies and it feels bad when it happens.
Some other nitpicks on the gameplay includes: the asteroids look to samey to the background, which is hard to differentiate, unlike the sun and the mob enemies (red dwarfs). I also thought the arena area is a bit too small for this type of game, so it felt too restrictive.