Thanks. The stars actually are in 3D space - the whole game is 3D (rendering-wise, not gameplay-wise), just kinda very subtly. I feel like we could have leaned into that a bit more, but we were not sure how. We tried experimenting with a camera that tilts a little but that made it less clear if you were encircling a star or not since the gameplay itself is 2D. Even the worm itself is 3D (with a dynamically generated ArrayMesh). See here for an early visualization of it: 
Unfortunately we did not have enough time to include a tutorial / hints of some sort. So currently it is all just in the game’s description, which is less than ideal. The star color marks which civilization is controlling the star (think Stellaris if you played that).