Uranus’s Influence on Neptune’s Exterior Mean-motion Resonances
Severance Graham & Kathryn Volk (2024)
- Published
- Jun 1, 2024
- Journal
- The Planetary Science Journal · Vol. 5 · No. 6
- DOI
- 10.3847/PSJ/ad4707
At a GlanceAI
Uranus’s near-2:1 coupling with Neptune destabilizes Neptune’s distant exterior resonances, reducing scattering TNO resonance sticking beyond ~220 au.
SummaryAI
Neptune’s exterior mean-motion resonances can temporarily trap (“stick”) scattering trans-Neptunian objects as their semimajor axes evolve, but this effect weakens beyond ~200–250 au in standard simulations. This study shows the drop-off is not an inherent feature of scattering dynamics: removing Uranus keeps Neptune’s resonances strong for scattering TNOs to at least ~300 au. The culprit is Uranus–Neptune’s near-2:1 period ratio, whose induced variations in Neptune’s orbit destabilize high-e scattering TNO resonance libration beyond roughly the 20:1 resonance (~220 au), with additional mild weakening of closer resonances from direct Uranus–particle interactions. Because the Uranus–Neptune period ratio changed during planet migration, the paper implies that the ability of distant resonances to trap and sculpt scattering/detached TNO populations likely varied substantially over solar system history.
Method SnapshotAI
Extensive numerical N-body simulations varying the giant-planet configuration to measure resonance strength and sticking behavior in scattering TNOs.
BackgroundAI
Orbital dynamics of mean-motion resonances and the scattering trans-Neptunian population (celestial mechanics of the outer solar system).