Copernicus 450 ya

In 1543 a Polish astronomer called Copernicus put forward the idea, first thought of by the Greeks, that the Earth moved round the Sun. He showed how this could explain many of the movements of the planets. When, 50 years later, the Italian scientist Galileo pointed one of the first telescopes at the planets he could see that this idea was correct. As he watched night after night he saw moons orbiting the planet Jupiter.