Downloaded from of the orbit of Magnya subjected to the perturbations of the jovian planets for 70 My. Magnya is not presently involved in any resonance, and its motion is regular over the computed time span. The long-term behavior of the characteristic angle of the g s g5 s7 secular resonance is a prograde circulation with a period 1.37 My. The proximity of the asteroid to the secular resonance involving the longitudes of the perihelion and of the node affects the asteroid’s e and i and may explain their high values. About 200 asteroids have been observed in the Magnya region, and about 20 of these asteroids are presently involved in some mean-motion resonances showing chaotic behavior. The majority of the actual asteroids appear to avoid the chaotic domains that indicate the possible existence of important diffusion processes associated with the meanmotion resonances.

Our spectra and orbital dynamic simulations suggest that after the breakup of Magnya’s parent body, the fragments were scattered around a wide region depending on physical parameters such as the impact energy and the strength of the parent body and the sizes and velocities of the ejected fragments. The fragments that fell into the chaotic zones were slowly diffused out of the region, whereas Magnya, and possibly some other fragments, remained in stable orbits outside the zones of chaotic motion.