Until about 470 years ago, scientists thought that Earth was at the centre of all things in space. They saw the sun rising on one side of Earth, moving across the sky and setting on the other side of Earth, and concluded that the sun moved around the Earth.

In 1543, a Polish astronomer called Nicolaus Copernicus suggested that the sun, and not he Earth, was the centre of our solar system, and that the Earth and other planets move around the sun. Copernicus explained that the Earth rotates on its own axis once every 24 hours, causing the sun to appear to rise and set. This idea shocked the world at the time, and was only accepted many years after his death.