Scientists: if Venus ever had a moon like ours, it was doomed

Astrophysicist Stephen Kane of UC Riverside modeled the fate of a hypothetical Venus moon: due to the planet's slow rotation (243 Earth days per turn), the satellite almost always fell onto Venus, within 30 million to 1.7 billion years. The work was published in The Astrophysical Journal.

• Venus rotates once per 243 Earth days, so its gravity pulls a moon in rather than pushing it out
• Kane's simulations produced the same outcome in nearly all scenarios: the moon falls onto the planet
• A moon of half to 10 Earth masses fell faster the heavier it was
• NASA's DAVINCI mission in the early 2030s could test the hypothesis