Venus lacks a moon due to tidal physics, study finds

New research published in The Astrophysical Journal suggests that Venus lacks a moon due to natural tidal physics rather than an exotic planetary catastrophe. A study led by planetary astrophysicist Stephen Kane from the University of California, Riverside, utilized computer modeling to track the gravitational interactions between Venus, a hypothetical moon, and the Sun over billions of years.

The simulations indicate that in most plausible scenarios, any moon orbiting Venus would have spiraled inward and been destroyed by the planet’s gravity within the first billion years of its formation. This occurs when a moon crosses the Roche limit, the distance at which a planet’s tidal gravity exceeds the moon’s own gravity, causing the moon to be torn apart into a ring of debris.

According to Kane, a moon would only have survived under a very narrow set of conditions, specifically requiring a fast-spinning early Venus and a moon with a mass no greater than Earth’s Moon.