3 Reasons Why Venus Spins Backwards, According To Astronomers - SlashGear

There are three theories that explain how Venus came to spin the opposite direction of a majority of the planets.

The first theory is that Venus began its life spinning in the same direction as the other planets. But, like Uranus, it was hit by a large object, like a huge asteroid, perhaps even something the siz… [+1556 chars]

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