This is a nice game, although I feel like you could have done some more in order to add a bit of a challenge, such as have the larger black holes move around slowly. Also have planets and black holes of higher scales spawn in so once the current stuff is eaten up, there would still be more stuff to do. However, I like the visuals (and the black hole's distortion effect seems cool), and also that the larger planets get yoinked in once you reach a certain scale. Overall, great job!
P.S. I found a bug that doesn't reset your scale when you restart the game.