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arXiv · 2508.20780

Update of the CODE catalogue and some aspects of the dynamical status of Oort Cloud comets

Piotr A. Dybczyński·Małgorzata Królikowska
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Abstract

The outer Solar System is believed to host a vast reservoir of long-period comets (LPCs), but our understanding of their spatial distribution and dynamical history remains limited due to observational biases and uncertainties in orbital solutions for really observed comets. We aim to provide a comprehensive and dynamically homogeneous orbital database of LPCs to support the study of their origin, evolution, dynamical status, and 6D distribution of orbital elements. We updated the Catalogue of Cometary Orbits and their Dynamical Evolution (CODE catalogue) by computing original and future barycentric orbits, orbital parameters at previous and next perihelion, using full Monte Carlo swarms of real comets for the uncertainty estimation and taking into account the planetary, Galactic and passing stars perturbations according to the latest data and algorithms. This update of the CODE catalogue focuses on the dynamical status of near-parabolic comets. Using current stellar data, we formulated new constraints for dynamically new comets. Now, the CODE database includes 983 orbital solutions for 369 comets with full uncertainty estimates and dynamical classifications, covering nearly all comets with original semi-major axes exceeding 10,000\,au and discovered before 2022, as well as all LPCs discovered beyond 10\,au from the Sun during this period, and over 80\% of the known LPCs with perihelion distances beyond 7\,au.

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Piotr A. Dybczyński, Małgorzata Królikowska. 2025-09-17. Update of the CODE catalogue and some aspects of the dynamical status of Oort Cloud comets. https://doi.org/10.1051/0004-6361%2F202556678

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