Skip to main content# Dynamic evolution of pairs of trans-Neptunian objects

Presentation #350.01 in the session The Sun and the Solar System — iPoster Session.

Published onJun 29, 2022

Dynamic evolution of pairs of trans-Neptunian objects

We perform a search for statistically significant pairs of dynamically correlated objects through those with a semimajor axis greater than 30 au, applying a novel technique that uses Kholshevnikov metrics in the space of Keplerian orbits. The metric ρ_{2} defines the distance between two orbits in the five-dimensional space of Keplerian orbits. The metric ρ_{5} defines the distance in the three-dimensional factor-space of the positional elements. It gives the minimum distance between the orbits among all possible positions of the nodes and the pericenters. If the metrics ρ_{2} and ρ_{5} are small and have similar values, then such a pair of TNOs we considered as a candidate for young pair.

We have used the orbital elements from the AstDyS database. We found 26 pairs with metric ρ_{2} < 0.07 au^{1/2} (e.g., 2003 QL91 — 2015 VA173), 20 pairs in which one of the components is binary, for metric ρ_{2} < 0.12 au^{1/2} (e.g., (275809) 2001 QY297 — 2015 VB169), and 13 pairs of binary trans-Neptunian objects with metric ρ_{2} < 0.3 au^{1/2} (e.g., 2003 QY90 – 2005 CE81). All pairs belong to cold classical Kuiper Belt Objects.

We investigated the dynamic evolution and estimated the age of pairs based on the results of numerical simulations using the Orbit9 software from the OrbFit package. The Orbit9 integrated the major planets and the dwarf planet Pluto consistently. We searched for low relative-velocity close encounters of the TNO in pairs to estimate the age of the pairs. Two conditions for an approach. First, the distance between the TNO is of the order of the radius of the Hill sphere. Second, the relative velocity of the TNO is of the order of the escape velocity to the more massive TNO at the relative distance. We searched for the minimum metric ρ_{2} and simultaneous approaches of node lines and apse lines of objects orbits. We studied the probabilistic evolution for 10 Myr, and we considered 1000 clones for each TNO in pair. After that, we made the numerical integrations for 200 Myr, taking the nominal orbits given by the AstDyS database as initial conditions.

The work was supported by the Ministry of Science and Higher Education of the Russian Federation via the State Assignment Project FEUZ-2020-0038.