As R-r = a₁(1 + e) for the point of impact if the particle be wholly within the orbit of the planet and e the eccentricity of its orbit, we find

e = 2MR/r - RM/r approx.

for the case of no action, the other terms being insensible for the satellites in the table, since in all r < R/400.

Supposing, now, the particles within the orbit of the planet to be equally distributed according to their major axes, then as the velocity of any one of them, taking R-r = R approx. as unity, is

v₁ = (2/1 - 1/a₁)½,

the mean velocity of all of those which may encounter the satellite is, at the point of collision,

⌠¹
((2a₁ - 1)½ / a₁½) da
½

⸻⸻⸻⸻⸻

⌠¹
da
½
1
= 2 [(2a₁² - a₁)½ - 1/√(2) log{(2a₁ - 1)½ + √(2a₁)}]
½
= 0.754;