OSSOS. IX. Two Objects in Neptune's 9:1 Resonance—Implications for Resonance Sticking in the Scattering Population
Murray-Clay, Ruth A.
Gladman, Brett J.
Lawler, Samantha M.
Yu, Tze Yeung Mathew
Bannister, Michele T.
Dawson, Rebekah I.
Gwyn, Stephen D. J.
Kavelaars, J. J.
Lin, Hsing Wen
Lykawka, Patryk Sofia
AffiliationUniv Arizona, Lunar & Planetary Lab
KeywordsKuiper belt: general
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationKathryn Volk et al 2018 AJ 155 260
Rights© 2018. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractWe discuss the detection in the Outer Solar System Origins Survey (OSSOS) of two objects in Neptune's distant 9:1 mean motion resonance at semimajor axis a approximate to 130 au. Both objects are securely resonant on 10 Myr timescales, with one securely in the 9:1 resonance's leading asymmetric libration island and the other in either the symmetric or trailing asymmetric island. These objects are the largest semimajor axis objects with secure resonant classifications, and their detection in a carefully characterized survey allows for the first robust resonance population estimate beyond 100 au. The detection of these objects implies a 9:1 resonance population of 1.1 x 10(4) objects with H-r < 8.66 (D greater than or similar to 100 km) on Ksimilar orbits (95% confidence range of similar to(0.4-3) x 104). Integrations over4 Gyr of an ensemble of clones spanning these objects' orbit-fit uncertainties reveal that they both have median resonance occupation timescales of similar to 1 Gyr. These timescales are consistent with the hypothesis that these objects originate in the scattering population but became transiently stuck to Neptune's 9:1 resonance within the last similar to 1 Gyr of solar system evolution. Based on simulations of a model of the current scattering population, we estimate the expected resonance sticking population in the 9:1 resonance to be 1000-4500 objects with H-r < 8.66; this is marginally consistent with the OSSOS 9:1 population estimate. We conclude that resonance sticking is a plausible explanation for the observed 9:1 population, but we also discuss the possibility of a primordial 9:1 population, which would have interesting implications for the Kuiper Belt's dynamical his tory.
VersionFinal published version
SponsorsNASA Solar System Workings grant [NNX15AH59G]; NASA [NNX14AG93G]; NRC-Canada Plaskett Fellowship; UK STFC grant [ST/L000709/1]; Pennsylvania State University; Eberly College of Science; Pennsylvania Space Grant Consortium