👉 In physics, a precession is an effect of Earth's rotation that causes objects to rotate on their axis. It occurs when the Earth spins at a different rate from the rotational speed of its own spin. This means that the direction and speed of the object's motion are not exactly aligned with the angular velocity of the Earth's rotation. For example, if you stand on a stationary boat in the middle of a river, it will be spinning at a constant rate. However, when you stand on
