Nice game! The idea is nice, it is quite intuitive to pick up, and the art/audio is nice as well! Feels really polished.
It just misses a little oomph for me, maybe the fact that your reset to level ? I could not get passed level 3 and it went from fun to frustrating. Maybe a mechanic to push some planet away? Or just resetting on the same level? I am not sure, but it's that little something missing to make me want to come back to it.
But on the positive not, it looks really really good, I am really impressed! Great work :)