Dependence of Δa(For Ast1) on the binary asteroid’s relative orbit. The x-axis is the semi-major axis of binary relative orbit the y-axis is the change in the semi-major axis, both in log scale. Dots are from the grid simulations. To make the plot clearer, the dots have been shifted horizontally by a small but random amount (otherwise there are only four values for the x-axis: 200km, 2000 km, 20 000 km and 200 000 km). For panel a, Different colors are used for different μ (red 0.01, green 0.1, blue 0.99). The radii of Ast1 r₁ is 100 km. The three dashed lines are the predictions of Eq. (8). For panel b, different colors are used for different r₁ (red 1 km, green 10 km, blue 100 km, yellow 1000 km). The mass ratio μ is 0.99. The four dashed lines are the predictions of Eq. (7).