Neptune's 5:2 Resonance in the Kuiper Belt

Renu Malhotra, Lei Lan, Kathryn Volk, Xianyu Wang

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Observations of Kuiper Belt objects (KBOs) in Neptune's 5:2 resonance present two puzzles: this third-order resonance hosts a surprisingly large population, comparable to the prominent populations of Plutinos and Twotinos in the first order 3:2 and 2:1 resonances, respectively; second, their eccentricities are concentrated near 0.4. To shed light on these puzzles, we investigate the phase space near this resonance with use of Poincaré sections of the circular planar restricted three-body model. We find several transitions in the phase space structure with increasing eccentricity, which we explain with the properties of the resonant orbit relative to Neptune's. The resonance width is narrow for very small eccentricities but widens dramatically for e ≳0.2, reaching a maximum near e ≈ 0.4, where it is similar to the maximum widths of the 2:1 and 3:2 resonances. We confirm these results with N-body numerical simulations, including the effects of all four giant planets and a wide range of orbital inclinations of the KBOs. We find that the boundaries of the stable resonance zone are not strongly sensitive to inclination and remain very similar to those found with the simplified three-body model, with the caveat that orbits of eccentricity above ∼0.53 are unstable; higher-eccentricity orbits are phase-protected from destabilizing encounters with Neptune but not with Uranus. These results show that the 5:2 resonant KBOs are not more puzzling than the Plutinos and Twotinos; however, detailed understanding of the origins of eccentric, inclined resonant KBOs remains a challenge.

Original languageEnglish (US)
Article number55
JournalAstronomical Journal
Volume156
Issue number2
DOIs
StatePublished - Aug 1 2018

Fingerprint

Kuiper belt
Neptune (planet)
Neptune
eccentricity
orbits
inclination
Uranus (planet)
Uranus
eccentrics
encounters
planets
planet
orbitals

Keywords

  • Kuiper belt objects: individual (2013 UR15)
  • Kuiper belt: general
  • planets and satellites: dynamical evolution and stability
  • planets and satellites: formation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Neptune's 5:2 Resonance in the Kuiper Belt. / Malhotra, Renu; Lan, Lei; Volk, Kathryn; Wang, Xianyu.

In: Astronomical Journal, Vol. 156, No. 2, 55, 01.08.2018.

Research output: Contribution to journalArticle

Malhotra, Renu ; Lan, Lei ; Volk, Kathryn ; Wang, Xianyu. / Neptune's 5:2 Resonance in the Kuiper Belt. In: Astronomical Journal. 2018 ; Vol. 156, No. 2.
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