Nice Model of Giant Planet Evolution
(Morbidelli, Tsiganis, Gomes, & Levison)
- We recently developed a model of giant planet evolution that reproduces many observations.
- In particular:
- System is initially compact with Saturn inside of 1:2 MMR and a massive disk beyond planets.
- Jupiter and Saturn diverge until they hit the 1:2 MMR.
- The resonance excites the eccentricity of both Jupiter and Saturn
Uranus and Neptune go unstable.
- Uranus and/or Neptune scatter off of Saturn, keeping its eccentricity large.
- Uranus and Neptune settle to current orbits due to dynamical friction with the disk.
- This process reproduces the orbital elements of the giant planets fairly well.
- We put an edge to the disk near 30AU, which determines Neptune's location.
- Mass depletion problem is not a problem.
- The other orbital elements are only sensitive to one free parameter - disk mass.
- Needs a disk of about 35M⊕.
- The other free parameters really only effect the time of resonance crossing.