Sorry if this is the wrong place, but I thought Iād share my complete project. 
I added a rotating solar system backdrop to my levels using textures I found online. The sun is using an emission material and I have a omni light inside it.
I also modeled my own rocket in blender based on a rocket emoji I found on google.
Finally, I used the VisibleOnScreenNotifier3D node to kill the player if they go off-screen.
