Title page of 'Dialogue' by Galileo, 1632.
© Science Museum / Science & Society Picture Library
Title page of 'Dialogo' ('Dialogue on the two chief world systems') by Galileo Galilei (1564-1642), published in Florence in 1632. Italian astronomer and physicist Galileo is one of the greatest scientists and his achievements include the discovery of Jupiter's moons and the laws governing falling bodies. In Dialogo, Galileo defended the Copernican planetary system which states that the planets revolve around the sun. The sale of the book was prohibited by the catholic authorities, and Galileo was forced to recant under the threat of torture, after which he lived under house arrest.