Astronomy Astronomers study one of physics' most fascinating subjects - outer space.
Astronomy is the study of all that is found in space.
It includes everything from amateur star-watching with an ordinary pair of binoculars to the very precise measurements taken by astronomers when they analyse the radio waves given off by stars in distant galaxies. For example, Aristotle, who lived around 400 BC, described the motion of the planets in his work On the Heavens . Aristotle's ideas were accepted until the 1500's when Copernicus suggested that the sun, and not the earth, was at the centre of the universe. Astronomers study many interesting things in space, like planets, galaxies, meteors, comets, and asteroids. Of course, astronomers also study stars.