Secular resonance
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A secular resonance is a type of orbital resonance.
Secular resonances occur when the precession of two orbits is synchronised (a precession of the perihelion, of the ascending node, or both). A small body in secular resonance with a much larger one (e.g. a planet) will precess at the same rate as the large body. Over long times (a million years, or so) a secular resonance will change the eccentricity and inclination of the small body.
The effects of secular resonances are most studied in the context of the long-time evolution (millions of years or more) of minor planet orbits within the Asteroid belt.
One can distinguish
- linear secular resonances between a body and a single other large perturbing body (e.g. a planet), and
- nonlinear secular resonances involving more than one large body.[1]
[edit] ν6 resonance
A prominent example of a linear resonance is the ν6 secular resonance between asteroids and Saturn. Asteroids which approach it have their eccentricity slowly increased until they become mars-crossers, at which point they are usually ejected from the asteroid belt due to a close pass to Mars. This resonance forms the inner and "side" boundaries of the main asteroid belt around 2 AU, and at inclinations of about 20°.
[edit] References
- ^ V. Carruba et al (2005). "On the V-type asteroids outside the Vesta family". Astronomy & Astrophysics 441: 819.
