The constellation Virgo, 1603.
© Science Museum / Science & Society Picture Library
Illustration taken from 'Uranometria' (1603) by Johann Bayer, showing the constellation of Virgo (the Virgin). 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. The second largest constellation in the night sky, Virgo is notable for containing a supercluster of galaxies. 11 of the 103 galaxies and nebulae clasified in the 18th century by the French astronomer Charles Mesier (1730-1817) are situated in Virgo. Only Sagittarius, with 15, contains more.