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We discuss the detection in the Outer Solar System Origins Survey (OSSOS) of two objects in Neptunes distant 9:1 mean motion resonance at semimajor axis $aapprox~130$~au. Both objects are securely resonant on 10~Myr timescales, with one securely in the 9:1 resonances 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 $1.1times10^4$ objects with $H_r<8.66$ ($D~gtrsim~100$~km) on similar orbits (95% confidence range of $sim0.4-3times10^4$). Integrations over 4~Gyr of an ensemble of clones spanning these objects orbit fit uncertainties reveal that they both have median resonance occupation timescales of $sim1$~Gyr. These timescales are consistent with the hypothesis that these objects originate in the scattering population but became transiently stuck to Neptunes 9:1 resonance within the last $sim1$~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 belts dynamical history.
We report the discovery and orbit of a new dwarf planet candidate, 2015 RR$_{245}$, by the Outer Solar System Origins Survey (OSSOS). 2015 RR$_{245}$s orbit is eccentric ($e=0.586$), with a semi-major axis near 82 au, yielding a perihelion distance o
Observations of Kuiper belt objects (KBOs) in Neptunes 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:
We report the Transiting Exoplanet Survey Satellite ($TESS$) detection of a multi-planet system orbiting the $V=10.9$ K0 dwarf TOI 125. We find evidence for up to five planets, with varying confidence. Three high signal-to-noise transit signals corre
Resonant dynamics plays a significant role in the past evolution and current state of our outer Solar System. The population ratios and spatial distribution of Neptunes resonant populations are direct clues to understanding the history of our planeta
We present spectroscopic measurements of the Rossiter-McLaughlin effect for the planet b of Kepler-9 multi-transiting planet system. The resulting sky-projected spin-orbit angle is $lambda=-13^{circ} pm 16^{circ}$, which favors an aligned system and