List of my modifications:

  1. 9 planets and 3 satellites.
  2. The relative orbits are in scale with real ones.
  3. The relative sizes of planets and satellites are in scale with  real ones, but 1000 larger then orbits. Sun is 10 times smaller.
  4. The periods of orbital and self rotation are in scale with real ones.
  5. Colorful trails to track orbits.
  6. Several comet spawners to add some randomness to comets.
  7. Made all planets and rotations into prefabs and scriptable objects, so you can easily add more.
  8. I actually added a tool to modify time and scale in Unity on the go, but didn't have time to made it into UI.
  9. Added scale marks and timer, but that realy depends on your PC.
  10. Zoom-In option on click.
  11. Had so much fun!

Download

Download
Windows.zip 25 MB
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MacOS.zip 35 MB