YS coefficient for the primary as a function of the ratio of spin velocity to mean motion. The primary asteroid has a radius of 1 km, and the secondary has a radius of 0.3 km. Gold circles represent the numerical results. The solid gold curve shows the simple analytical solution from Eq. (6), while the dashed gold curve shows the modified solution from Eq. (12) with α = 1.7. The ω_p/n distribution of confirmed binary asteroids is depicted in the blue histogram, which is truncated at 10.