Really cute graphics, the game looks very nice!
I had some trouble with the controls at first since it was a lot to take in, but after playing the game for a bit I figured it out! Using the thrusters alongside switching between gravity/no gravity was a little difficult though! Maybe because the thruster particles are actual objects? Since you're using Unity, I'd personally use Particle Systems!
Regardless, I do like the story you've created inside of the game, I think it's very cute