Ole Rømer was most of all an astronomer. In 1672 he discovered the speed of light, at that time it was called the hesitate of the light. In 1681 he became professor at the University of Copenhagen. Besides being a professor, he also worked as mayor of Copenhagen and as chief constable.

He carried out a new system for weights and measures in Denmark, so a Mile or a Pound were equal all of the whole country.

Other Danish scientists: Niels Bohr Tycho Brahe Ole Rømer