Even though we don’t feel it happening, the Earth is rotates completely once every day. If the Earth didn’t rotate there wouldn’t be night and day as we know it. There would be a sunny and dark side of the Earth, which would only change once a year. The sunny side would get very hot, while the dark side would be very cold. It is for this reason that the rotation of the Earth is considered to be an important ingredient for sustaining life. Have you ever wondered what makes the Earth rotate? Read on to find out the answer.
Why does the earth rotate?
There are a number of theories about what caused the Earth to rotate as it does today, but the most reliable and widely accepted is due to leftover momentum from when Earth formed. Basically, all planets rotate because of the way they form. This following a brief description of the formation of a planet:
As gravity pulls matter closer there is a great deal of potential energy. This potential energy turns into kinetic energy and makes the particles come together. As these particles meet and join together the kinetic energy remains. This turns into rotational kinetic energy and causes the planet to rotate. The reason that the planet continues to rotate many years later is that space is a vacuum and there is nothing to stop the rotation. It is believed that the Sun will expand into its red giant phase well into the future and the gravitational forces will eventually stop the rotation of the Earth.