Copernicus, Nicholas (1473–1543)
- Polish astronomer who established the idea that the Earth moves through space while the Sun stands still at the centre of a solar system of planets. This scheme, now accepted almost universally, is known as the Copernican system. His great book ‘De Revolutionibus Orbium Coelestium’ used his own and others’ observations to demonstrate that this logic – using a circular orbit for the Earth rather than the elliptical ones introduced by Kepler – was a simpler way of explaining the apparent movement of the planets. At the time he first published these thoughts the Catholic church, of which he was a Canon, was more amenable to the idea than it later became in its dealings with Galileo and others. But Copernicus’s ideas – developed at a time of great upheaval, with Copernicus himself caught up in the warfare of the reformation – did not catch on in his own lifetime, and the first copy of ‘De Revolutionibus’ was brought to Copernicus on his deathbed. The Copernican principle is the idea that the Earth’s position in the universe is not special, one of the most powerful ideas in science. The astronomical observatory Copernicus was launched in 1972 for ultraviolet astronomy.