Sonify orbits

[avivajpeyi]

It'd be cool if we could sonify the orbits, similar to how SYSTEM Sounds does.

[avivajpeyi]

• [ ] assign sound to planet based on radius from center
• [ ] if the planet reaches the initial position (complete 1 period), play planet's sound

[avivajpeyi]

To play sound clip: https://gamedevbeginner.com/how-to-play-audio-in-unity-with-examples/

[avivajpeyi]

See #9