Date context
1564–1642
Teaching and mathematics
Born in Pisa, Galileo initially studied medicine before turning to mathematics. Teaching in Pisa and later Padua, he investigated motion, mechanics and instruments. University employment, private instruction and instrument-making provided the practical setting for this work.
References: [1]
Evidence through the telescope
From 1609 he improved telescopes for astronomical observation. His 1610 Sidereus Nuncius reported discoveries including Jupiter’s satellites. Bodies orbiting Jupiter showed that celestial motion need not all centre on Earth; that observation alone did not establish Earth’s motion around the Sun.
References: [1]
Publication and trial
The Dialogue Concerning the Two Chief World Systems appeared in 1632. In 1633 the Roman Inquisition tried Galileo and required him to renounce claims about Earth’s motion. His sentence of imprisonment was subsequently served under house arrest.
References: [2]
The study of motion
Astronomical controversy was only part of his work. Galileo also studied falling bodies, inclined planes and projectiles, seeking mathematical descriptions of repeatable phenomena. These investigations should be considered alongside, rather than reduced to, the much better-known trial.