Polar Orbits around the Newly Formed Earth-Moon Binary System

We examine the dynamics and stability of circumbinary particles orbiting around the Earth-Moon binary system. The moon formed close to the Earth (semimajor axis a EM approximate to 3 R circle plus) and expanded through tides to its current day semimajor axis (a EM = 60 R circle plus). Circumbinary orbits that are polar or highly inclined to the Earth-Moon orbit are subject to two competing effects: (i) nodal precession about the Earth-Moon eccentricity vector and (ii) Kozai-Lidov oscillations of eccentricity and inclination driven by the Sun. While we find that there are no stable polar orbits around the Earth-Moon orbit with the current day semimajor axis, polar orbits were stable immediately after the formation of the Moon, at the time when there was a lot of debris around the system, up to when the semimajor axis reached about a EM approximate to 10 R circle plus. We discuss implications of polar orbits on the evolution of the Earth-Moon system and the possibility of polar orbiting moons around exoplanet-moon binaries.