For the 2026 Perseids’ parent comet, one orbit takes the time Jupiter takes to complete 11 orbits.
This relationship is called a 1:11 orbital resonance with Jupiter. Comet Swift–Tuttle follows a long, elongated, retrograde orbit around the Sun, while Jupiter completes its much shorter orbit about once every 12 years. The resonance describes a repeating gravitational timing relationship rather than the comet traveling alongside Jupiter.
Orbital resonances can influence the long-term evolution of small bodies by repeatedly arranging gravitational encounters in related positions. In Swift–Tuttle's case, the resonance is notable because it helps describe the dynamical setting of the comet that supplies the Perseid meteoroid stream.
The resonance is separate from the shower's annual visibility. Earth crosses the comet's dust trail every year in July and August, even though Swift–Tuttle itself takes roughly 133 years to circle the Sun. The comet last passed perihelion in 1992 and is expected to return in 2126.