A California-based astrophysicist has proposed a new theory explaining why Venus does not have a moon.

Researchers at the University of California, Riverside, say Venus’ extremely slow rotation would have caused any moon to gradually spiral toward the planet and eventually crash into it.

Computer models showed that hypothetical moons of different sizes would all have met the same fate.

Scientists believe the moon-destroying collision likely happened within Venus’ first billion years, Reuters has reported.

The theory differs from earlier ideas that Venus either never had a moon or lost one in a massive collision with another celestial body.