New computer simulations suggest that Venus may have once possessed a moon, but the planet's extremely slow rotation likely sealed the moon's fate. The research indicates that instead of gradually drifting away from Venus as Earth's moon does, a Venusian moon would have spiraled inward over time.
The slow rotation would disrupt the typical tidal interactions that push moons outward. In the simulations, the moon's orbit decayed until it eventually crashed into the planet's surface. This offers a plausible explanation for why Venus has no moon today, even if one formed early in the solar system's history.
While the study does not confirm that Venus actually had a moon, it provides a mechanism for how such a moon could have been lost. The findings add to our understanding of planetary evolution and the role that rotation plays in shaping moon systems.