2013/12/29 by Alessandro Morbidelli, A. Morbidelli, H. S. Gaspar +2 · 5 citations
Physics and Astronomy · #Astro and Planetary Science #Planetary Science and Exploration #Stellar, planetary, and galactic studies #astro-ph.EP
paper · pdf · doi:10.1016/j.icarus.2013.12.023
in press in Icarus
arxiv created 2013/12/29 · openalex publication_date 2014/01/15 · arxiv updated 2015/06/18 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Dawson and Murray-Clay (2012) pointed out that the inner part of the cold population in the Kuiper belt (that with semi major axis a<43.5 AU) has orbital eccentricities significantly smaller than the limit imposed by stability constraints. Here, we confirm their result by looking at the orbital distribution and stability properties in proper element space. We show that the observed distribution could have been produced by the slow sweeping of the 4/7 mean motion resonance with Neptune that accompanied the end of Neptune's migration process. The orbital distribution of the hot Kuiper belt is not significantly affected in this process, for the reasons discussed in the main text. Therefore, the peculiar eccentricity distribution of the inner cold population can not be unequivocally interpreted as evidence that the cold population formed in-situ and was only moderately excited in eccentricity; it can simply be the signature of Neptune's radial motion, starting from a moderately eccentric orbit. We discuss how this agrees with a scenario of giant planet evolution following a dynamical instability and, possibly, with the radial transport of the cold population.