It isn’t hard to find the influence of Galileo Galilei (1564–1642) on the history of astronomy. After all, he was the first to use a telescope to study the heavens systematically and objectively. He discovered the Moon’s craggy mountains, Jupiter’s four major satellites, and the phases of Venus.

But that’s Galileo the scientist. Who was the man?

To find some clues, I went to Rome and Florence, where Galileo spent the prime of his life and ended up under house arrest for life after a disastrous encounter with the Roman Catholic Church. I decided to retrace the master’s footsteps in Italy — to visit the places where he lived and worked in hopes of absorbing something of the spirit of the times in the 17th century when Galileo helped overturn what people thought they understood about the celestial realm.