Illustration taken from 'Uranometria' (1603) by Johann Bayer, showing the star constellation of Ursa Major (the Great Bear). German astronomer and lawyer Johann Bayer (1572-1625) invented the system for naming stars using letters from the Greek alphabet, a system still used today for the brighter stars - those visible to the human eye without the aid of a telescope. 'Uranometria' depicts the positions of nearly 1000 stars in addition to those identified by Tycho Brahe. Ursa Major is posibly the best known of all the constellations as it contains the group of stars known as the Plough or the Big Dipper, which form the tail of the bear. It has traditionally been useful to navigators as a means of locating nearby Polaris, the North or Pole Star.
© Science Museum / Science & Society Picture Library