15 February: Galileo Galilei

Born on this date in 1564 was Galileo Galilei. 10 facts about him:

1. While it may seem strange to us for a person’s given name and surname to sound so similar, back when Galileo was born, people would generally only use one name, occasionally supplemented with their occupation, town of origin, father’s first name or traditional family name. The name Galileo actually means “of Galilee”.

2. Galileo’s father Vincenzo was a musician and composer. He played the lute, and apparently some of his compositions can still be purchased as modern recordings on CD today. Hence Galileo himself learned a lot about Music as he was growing up. He could play the lute, too, and was also well versed in art, considering a career as a painter at one point.

3. He also considered the religious life. As a boy, he studied at a monastery and decided he wanted to become a monk. However, his father didn’t want that life for his son and eventually intervened by taking him out of that school.

4. When Galileo started university he was studying medicine, but soon realised he was much more interested in maths and began studying that instead. He never completed his studies, though, as in 1585, financial constraints meant he had to drop out. However, he continued to study on his own, supplementing his income by giving private lessons. He became a teacher at the university in 1589.

5. His family weren’t well off, and as well as supporting himself, Galileo found himself having to support his siblings. His younger brother Michelangelo became a musician but not an especially successful one and often borrowed from his older brother to support his musical projects. Galileo also found himself having to pay the dowries his father had promised for his sisters. It may be that his inventions, such as the thermoscope and military compasses, were inspired by a need to make money. He also made money by teaching students about Astrology and how to cast horoscopes. At the time, such knowledge would have been in great demand. As well as family support, Galileo wasn’t keen on the university dress code for teachers and often refused to wear the required formal robes, for which his pay would be docked.

6. While he didn’t actually invent the Telescope – Dutch eyeglass maker Hans Lippershey is generally credited with that – but he did make improvements to Lippershey’s designs. Back then, telescopes were used for looking at things on Earth, such as sailors using them at sea. Galileo was the first person to think of looking at the Sky with them. Until Galileo looked at the Moon with a telescope and observed the mountains and craters, it was generally believed that the moon’s surface was smooth.

7. Galileo never married but he did have a lover called Marina Gamba, and had three children with her, two girls and a boy. Concerned that his illegitimate girls would never find husbands due to the stigma, he put them both in a convent where they stayed all their lives. Galileo’s son, Vincenzo, born in 1606, studied medicine at the University of Pisa, married well in spite of being born out of wedlock, and lived in Florence.

8. Galileo’s observations led him to support the 1543 theory of Nicolaus Copernicus, that the Sun is the centre of the universe and the Earth and other planets revolve around it. The Catholic Church, however, declared Copernicus’s theory heresy and while they didn’t forbid Galileo from studying Copernicus’ ideas, he wasn’t allowed to hold or defend them. Never one for doing as he was told, Galileo published a book about it anyway in 1632: Dialogue of the Two Principal Systems of the World. It was presented as a discussion between friends about the ideas of Ptolemy and Copernicus, but the book was seen as supporting the Copernican model and Galileo was sentenced to life in prison.

9. However, the sentence was commuted to house arrest, so he spent his final years at Villa Il Gioiello (“the Jewel”), his home in the town of Arcetri, near Florence. Although he wasn’t allowed to see friends, he had plenty of visitors including philosopher Thomas Hobbes and poet John Milton. He was forbidden from publishing books as well, but nevertheless managed to smuggle out a manuscript for a book called Discourses and Mathematical Demonstrations Concerning Two New Sciences, about physics and mechanics, which was published in The Netherlands in 1638.

10. When Galileo died in 1642 at the age of 77, the Vatican refused to allow his remains to be buried alongside family members in Florence’s Santa Croce Basilica. He had to be buried in a side chapel instead. About 100 years later his reputation had improved and his remains were moved to the main basilica, although a few of his body parts went missing in the process. The middle finger of his right hand has been housed at various museums in Italy since the early 1800s.