This image shows different objects that rotate. Rotational period is the time it takes for that object to rotate just once.

Rotational Period

Rotational period is the time it takes for a planet or moon to spin around once. On Earth, this time is 1 day.

Venus spins very slowly! Scientists think this is because a long time ago something big hit Venus and slowed down its rotation. Now, Venus spins so slowly that it revolves around the Sun faster than it spins on its own axis. That means that a Venus day is longer than a Venus year!

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