Galilei, Galileo (1564–1642)

Italian mathematician, astronomer, and physicist Galileo Galilei is considered to be the founder of the modern scientific method. He pioneered verification by experimentation and critical analysis of phenomena. Galileo was the first person to use a telescope to make and interpret systematic astronomical observations and made many discoveries regarding the solar system. Galileo's observations of the eclipses of Jupiter's moons led to his discovery of a cosmic clock that, in effect, recorded absolute time. The Galilean transformations of space and time variables led to the development of the Newtonian laws of mechanics. His theoretical work in physics laid the groundwork for the future exploration of relativity and the laws of motion. Although Galileo himself did not invent the pendulum-regulated clock, his initial designs inspired others to do so. His preliminary research and design of an escapement mechanism led to the development of the first pendulum-regulated timepiece. Galileo's quest to measure very small quantities of time accurately paved the way for discoveries about sound and light waves that eventually led to modern investigations of quantum physics.

Galileo was born in Pisa, Italy, on February 15, 1564. He was the first of six, possibly seven children born to Vincenzo Galilei, a musician, composer, and wool trader; their mother was Giulia Ammannati of Pesscia. Three days later the famous artist Michelangelo died. Leonardo [Page 556]da Vinci had passed away 45 years prior to Galileo's birth. Nicholas Copernicus had been dead for 21 years. William Shakespeare would be born 2 months later. This was the time of the Renaissance. A new awakening had arrived for philosophy, music, art, the sciences, literature, and discovery.

Figure: Galileo first put forth his observations on the moons of Jupiter in his book Siderius Nuncius. He studied Jupiter over the course of a month and was able to show the movement of the satellites around Jupiter

Source: Library of Congress, Prints & Photographs Division, LC-USZ62–7923.