Mean-motion resonances in the Solar system
A curated collection of essential papers on mean-motion resonances in the asteroid belt, TNO, and beyond.
T. Gallardo (2006)
Numerical atlas ranks mean-motion resonance strengths across the Solar System and flags unexpectedly strong, populated resonances.
This paper fills a practical gap in celestial mechanics: while resonance locations are easy to compute, their relative dynamical “strength” (especially at nonzero inclination) is not. Gallardo introduces a numerical way to compute a resonance's averaged disturbing function as a function of the critical angle, and defines a simple strength metric from its amplitude to build an "atlas" of resonance strengths from Mercury to Neptune out to 300 au for representative small-body orbits. The atlas predicts several surprisingly strong high-order resonances, and the author confirms this by identifying real asteroids, centaurs, and TNO/scattered-disk objects currently librating in a number of unusual resonances (including new co-orbital candidates and very high-order Neptune resonances). A key implication is that resonance importance cannot be inferred from order alone: inclination and argument of perihelion can strongly reshape resonant dynamics and shift libration centers, affecting capture and long-term transport routes of minor bodies.
Numerical averaging of the planet–particle disturbing function over resonant geometry to map resonant potential shape and derive a resonance-strength metric.
Orbital dynamics/celestial mechanics basics, especially mean-motion resonances and disturbing-function concepts.
A systematic study of the influence of MMRs in the Solar system and a useful metric — strength of the resonance.
— ES