If 𝜃 < 𝜃 , ∆𝐸 > 0, whereas 𝜃 > 𝜃 , ∆𝐸 < 0. As vt tangents a cycle, 𝜃 = , the maximum ∆𝐸 attains. If A is far enough, 𝜃 ≈ . 𝜃 = is achievable. Furthermore, if 𝜃 = and 𝐹 = 0, A will cycle B with vt. Apart from the attractive force, as A approaches B, θ increases, while as A leaves B, θ decreases. Hence, Eq. 24 describes the elliptic motion. In addition, increasing v0 lifts the frequency of motion and ∆𝐸 . However, since θ is dependent on L, increasing θ0 lowers the frequency but increases the long radius of the ellipse. Therefore, for escaping from B, changing θ0 is more effective. Moreover, Eq. 28 implies that the kinetic energy of a particle will gradually decrease even though it escapes from a planet and travels in a vacuum.