1. Galileo the heretic
Much of Galileo’s work was withdrawn and banned during the 17th century by order of the Church. It wasn’t until 1718 that reprinting was allowed again.
2. More inventions
In addition to the objective lens and thermoscope, Galileo also invented a geometric compass, a microscope, a pendulum clock and contributed greatly to many other technologies too.
In 1638 – towards the end of his life – Galileo went blind. Yet even in his final few years he continued with his work, taking on an apprentice to help him who was with Galileo until his death.
4. Not always right
Sometimes Galileo was far from being correct. For example, he disagreed with Kepler’s theory that the Moon caused the Earth’s tides and believed that they were down to the rotation of the Earth and orbit of the Sun.
5. Jupiter’s moons
Galileo discovered the Jovian moons Io, Callisto, Ganymede and Europa, naming them the Sidera Medicea (Medicean stars) after his patron Cosimo II de’ Medici. They were later renamed the Galilean moons.