The giant planets of the Solar System host systems of multiple moons, where the Earth has only one large natural satellite, Luna. There are many man-made satellites in residence around the Earth and a handful of small asteroids that can persist as temporary natural satellites. With this observation, one can wonder how many large natural satellites (i.e., moons) could orbit the Earth over long timescales. We perform a series of N-body simulations that consider three different satellite masses (Ceres-, Pluto, and Luna-like), where each mass type is nested around an Earth-mass planet orbiting a Sun-like star. The innermost moon begins orbiting near the host planet’s Roche radius, while additional moons are added using the mutual Hill radius between adjacent satellites. Our simulations reveal, as an upper limit, that an Earth-mass planet could host up to 7 Ceres-mass, 4 Pluto-mass, or 3 Luna-mass moons with an uncertainty of 1 moon respectively. However, the true limitation for moons is likely to be fewer than these upper limits as gravitational interactions with other planets can periodically alter the extent of the host planet’s Hill radius or outward tidal migration (due to interactions with the host planet itself) can force collisions or scattering events.

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