Hilda asteroids don't maintain 3:2 orbital resonance with Jupiter over long time-scales

[charliewhitfield]

Hilda orbits degrade and spread out over centuries from J2000, loosing their initial "triangle" clustering (with outer points inside of Jupiter's L3, L4 and L5). There is no mechanism in the code to keep Hildas in 3:2 orbital resonance with Jupiter.

They should maintain 3:2 orbital resonance with Jupiter: https://en.wikipedia.org/wiki/Hilda_asteroid.

I'm pondering more general solutions to resonance that would also include 1:1 (Trojans) or any other ratio. Also, asteroid code is a mess. (It's some of the earliest code in the project and I'm a better coder now than in 2018.)

[charliewhitfield]

The fix is getting close! The problem is that we don't have orbital precessions for asteroids. (We do for planets and moons.) The rate around the sun is the sum of mean orbital motion plus the two orbit precessions: nodal and apsidal. Not having precessions unsyncs their orbit from Jupiter over a few centuries.

All the needed infrastructure is present now in v0.0.14. The precessions are in the asteroid binaries and passed to the asteroid shaders. I just need to implement the precessions!