resonance orbit

astronomy

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July 13, 2026

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In astronomy, an orbital resonance occurs when two or more celestial bodies exert a regular, periodic gravitational influence on each other, usually because their orbital periods are related by a ratio of small integers. This gravitational interaction can stabilize their orbits.1

For example, some asteroids are in orbital resonance with Jupiter. The Trojan asteroids share Jupiter's orbit in a 1:1 resonance, while the Hilda group is in a 3:2 resonance. These resonances can create gaps in the distribution of asteroids, known as the Kirkwood gaps. Orbital resonances are also observed among the moons of major planets, such as Jupiter's moons Io, Europa, and Ganymede, which are in a 1:2:4 resonance.1

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asteroid
Distribution and Kirkwood gaps
…in a three-to-one (written 3:1) resonance orbit with Jupiter. Consequently, once every three orbits, Jupiter and an asteroid in such an orbit would be in the same relative positions, and the asteroid would experience a gravitational force in a fixed direction. Repeated applications of that force would eventually change the…
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…in a three-to-one (written 3:1) resonance orbit with Jupiter. Consequently, once every three orbits, Jupiter and an asteroid in such an orbit would be in the same relative positions, and the asteroid would experience a gravitational force in a fixed direction. Repeated applications of that force would eventually change the…
Read More

meteorite
Cosmic-ray exposure ages of meteorites
…the asteroid belt until their orbits intersect a resonance—i.e., a region in the belt where they experience strong gravitational perturbations by the planets, particularly Jupiter—that puts the meteoroids in Earth-crossing orbits. The general drop-off in the frequency of meteorites with older exposure ages and the upper limit for most stony…
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…the asteroid belt until their orbits intersect a resonance—i.e., a region in the belt where they experience strong gravitational perturbations by the planets, particularly Jupiter—that puts the meteoroids in Earth-crossing orbits. The general drop-off in the frequency of meteorites with older exposure ages and the upper limit for most stony…
Read More