Genuinely a very pleasant idea. I love unpausing/pausing the game trying to get the planets to give me the perfect trajectory to my goal. Id love to see some sort of representation of where the ball would be going initially, like how pool games usually have a fading line showing your trajectory. It would also be helpful to have some sort of representation of how fast planets are moving when paused. Another thing that confused me was how the score is drawn from your actions.
But yeah. Super novel idea, I'm surprised I haven't played a game like this before as it could be super fun if properly fleshed out into a full game. Nice work!