ZME SCIENCE - Venus has no moon today. But it may not always have been alone.
A new study suggests that if a giant impact gave early Venus a substantial moon, tidal forces could eventually have reversed the satellite’s path and dragged it back toward the planet. Venus would then have torn the moon apart, briefly producing a ring before much of the debris fell onto the world below.
The study, which will soon appear in The Astrophysical Journal, does not show that Venus ever had a moon. Stephen Kane of the University of California, Riverside, and his colleagues wondered if Venus formed one, could it still be there today? Their answer depends heavily on how fast Venus spun after the impact, the moon’s mass and how the planet’s interior responded to tides.