The Earth's been spinning like a top since it began, about 4.6 billion years ago. Swirling clouds of dust and gas came together to form solid chunks of matter, explains 3-2-1 Contact magazine. These chunks turned in circles in the direction the clouds moved. Once an object starts spinning, it keeps going until something makes it stop. That's why the Earth, planets and moons still spin today.
Earth takes about 24 hours to spin once in a circle. At the equator, the Earth moves at a speed of about 1,000 miles per hour!But our world is slowly slowing down. Every day, Earth's oceans creep up at high tide and retreat at low tide. This ocean motion causes friction - the same forces that stop a bicycle wheel's spin. About 50 years from now, your day might last an extra 15 seconds.