I didn't know that. Although it seems as though they're sufficiently far outside what its makers thinks Unity is for that their attempt to go to Unity 5 had big obstacles. Thanks for correcting me!

[Also, another way I was wrong: to make Unity work the centre of the world is the player, and so the universe is implemented in reverse, your orbit around the sun is calculated with you at the middle, this works correctly in our actual Einsteinian universe - no position is privileged, there is no "center", but it would be crazy to do the maths, for the short time Outer WIlds needs it works well enough with their simple Newtonian physics model]