Chirikov diffusion in the sphere–ellipsoid binary asteroids

The Chirikov diffusion in the sphere–ellipsoid binary asteroids through the spin–orbit resonance model is analytically and numerically studied. The primary and the secondary of the binary system are considered sphere and ellipsoid, respectively. The gravitational potential function is expanded up to the fourth-order. The geography of the first- and second-order resonances is derived and studied for different values of asphericity and dynamical flattening of the secondary asteroid and the semimajor axis and eccentricity of the mutual orbit. The Chirikov diffusion due to overlapping of the first- and second-order resonances is examined. For this end, the previously derived criterion for appearance of large-scale chaos is modified for those binary asteroids in which their secondary has irregular shape.