Implementation of secular resonance support in the open-source python package "resonances"(pdf)
Smirnov, Evgeny A. · 2026 · Astronomy and Computing
At a GlanceAI
Adds full secular resonance detection to the Python package resonances with flexible frequency parsing and secular-timescale libration tests.
SummaryAI
The paper extends the open-source Python package "resonances" from mean-motion resonances to full identification and analysis of secular resonances. It introduces a flexible parser for arbitrary combinations of fundamental precession frequencies (g, s and indexed terms), enabling both classic linear resonances (e.g., ν5, ν6, ν16) and 70+ nonlinear resonances from the literature. New libration-detection algorithms are tailored to secular timescales with automated parameter adaptation for long integrations, and the secular tools are integrated into the existing mean-motion workflow via consistent interfaces. Validation through automated tests and literature-based examples suggests the implementation is reliable for systematic dynamical studies (including asteroid family applications), with minor exceptions noted.
If you need to identify whether or not an asteroid is trapped in secular resonance, this is the package for you.
— ES
- Method:AI
- Software implementation and validation of secular-resonance identification via expression parsing plus secular-timescale libration detection, tested against literature cases.
- Background:AI
- Basic celestial mechanics of secular resonances (g/s frequencies, ν-type resonances) and familiarity with numerical orbit integration workflows in Python.