The study of the Universe is a subject that interests all of humanity. Throughout history, our view of the world and the stars that surround us has changed dramatically several times.

Europeans used to believe that the Earth was at the centre of the Universe and that the Sun, planets and all the stars revolved around it. In 1543, an astronomer named Nicholas Copernicus proposed that the Earth and all the planets orbited the Sun. In fact, he believed that the Sun was at the centre of the Universe. During that same period of time, another astronomer named Tycho Brahe kept accurate measurements of the positions of the stars and planets. His student, Johan Kepler, later used these measurements to prove that all the planets, including Earth, orbited the Sun. At the same time, Galileo Galilei, an Italian scientist, first used a telescope to observe objects in the sky. Before this, people used to use the telescope only to observe objects on the Earth. Galileo discovered spots on the sun, a moon around Jupiter and craters on our Moon. This showed that the Earth is not much different than all the other objects in our Solar System. In previous centuries, scientists used to believe that Earth was very different from all the other planets. They also used to think that the planets and moons were perfect and didn’t have any spots or holes on them.

Today, scientists know that even Copernicus was wrong. He believed that the Sun was at the centre of the Universe. Instead, we now know that the Sun is only at the centre of the Solar System. The Solar System is made up of all the planets, including our own. The Sun is only one of billions of stars in our galaxy, called the Milky Way. Also, our galaxy is only one of billions, if not more, in our Universe.

Astronomy is one field in which scientists no longer follow the ideas that used to be accepted by everyone. Furthermore, the ideas in astronomy greatly influenced and continue to influence the way we humans see the Universe that we live in.

Written by Caitlin Myles