Callisto (Jupiter IV)

Sidereus nuncius, 1610

In this book Galileo reported the astronomical capabilities of his new spyglass. His drawings of the pitted lunar surface and Jupiter’s moons provided evidence to support theories of a Sun-centred Solar System. Sidereus nuncius could also be considered Galileo’s job application for a position at court in Florence. He called his newly discovered satellites of Jupiter ‘Medicean stars’ to impress the Grand Duke Cosimo II de Medici.