Title page from Galileo's book on astronomical theory, 1610.

Title page from 'Sidereus, nuncius magna' (known as 'The Starry Mesenger', Venice, 1610) by Galileo Galilei (1564-1642), a book of astronomical theory and observations. Galileo was an Italian astronomer and physicist and outstanding representative of the movement which transformed medieval natural philosophy into modern science. Regarded as one of the greatest scientists of all time, Galileo discovered Jupiter's moons and the laws governing falling bodies. Although Galileo was not the inventor of the telescope, he was the first to use it succesfully for astronomical observation.