Author(s)

Bijay Kumar Sharma

Department of Electronics and Communication, National Institute of Technology, Patna, India.

Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubation of much heavier planets such as Jupiter and Saturn if the natural satellite lies deep inside the respective host Planet Hill sphere. Each planet has a Hill radius a_H and planet mean radius R_P and the ratio R₁=R_P/a_H. Under very low R₁ (less than 0.006) the approximation of CRTBP (centrally restricted three-body problem) to two-body problem is valid and planet has spacious Hill lobe to capture a satellite and retain it. This ensures a high probability of capture of natural satellite by the given planet and Sun’s perturbation on Planet-Satellite binary can be neglected. This is the case with Earth, Mars, Jupiter, Saturn, Neptune and Uranus. But Mercury and Venus has R₁=R_P/a_H =0.01 and 5.9862 × 10^-3 respectively hence they have no satellites. There is a limit to the dimension of the captured body. It must be a much smaller body both dimensionally as well masswise. The qantitative limit is a subject of an independent study.

Hill’s Radius, Two-Body Problem, Fixed-Point Solution, Lagrange Points, Earth-Moon-Test Particle, CRTBP

Sharma, B. (2024) The Criteria for Reducing Centrally Restricted Three-Body Problem to Two-Body Problem. International Journal of Astronomy and Astrophysics, 14, 1-19. doi: 10.4236/ijaa.2024.141001.