What a cool little concept! To be completely honest I already had a blast just dragging the planets around and actually seeing the trajectory change in real time, I know that isn't too easy to do, so I always appreciate it when it's done well! The puzzles weren't too hard, and could have ramped up a bit more in difficulty, but the game wasn't too long so it was quite alright. I loved the little artstyle you had going here, but I do miss some space background music, to really emphasize the broadness of space! Plus sometimes the ship moves a little slow, I think you're actually using something to simulate gravity (?) but I think it would have been just fine to let the ship move along the trajectory at a steady speed, although I appreciate the attention to detail! Good job :)
Edit: my source as to why gravity etc is hard is that I made this game before: https://stevenkuperus.myportfolio.com/atmos