Capture radii given by Equations (21) and (22) as a function of . Dashed lines show the case of the prograde trajectories ( ), and dotted lines show the retrograde case ( ). Four sets of lines correspond to the cases with ζ = 10 ⁻⁴, 3 × 10 ⁻⁷, 3 × 10 ⁻⁹, and 10 ⁻¹¹, respectively, from top to bottom. The solid line shows the scaled physical radius of 10 ⁻³ (= , corresponding to a planet with density of 1 g cm ⁻³ at a = 5.2 AU.