He was born in Pisa, the Tuscany region of Italy, on February 15, 1564. He died in 1642 after studying and working in Florence, Italy.

He taught geometry, mechanics, and astronomy. During this time he explored science and made many landmark discoveries. Such as being the first to plainly state that the laws of nature are mathematical. Galileo also contributed to the separation of science from philosophy or religion, which was unheard in his lifetime. Mathematically, he asserted that the parabola was the theoretically-ideal trajectory, under the absence of friction and other disturbances. More remarkably, he stated limits to validate his theory. Galileo also gave much to the field of astronomy. He improved the telescope, was one of the first to use it to observe the sky, and for a time, was one of very few people able to construct one good enough to search space. With his telescopes he discovered three of Jupiter's four largest satellites; Io, Europa, and Callisto. He discovered Ganymede four nights later. He was one of the first Europeans to observe sunspots, and the first to report lunar mountains and craters, which he discovered from the patterns of light and shadow on the Moon's surface. He even estimated the mountains' heights from these observations. This led him to the conclusion that the Moon was "rough and uneven, and just like the surface of the Earth itself," rather than a perfect sphere as Aristotle had claimed. Along with the moon, Galileo observed the Milky Way and the planet Neptune. Although Galileo worked so hard at astronomy, he also contributed main ideas to the science of physics. Possibly the most important one being the theory he created on uniform acceleration.

Galileo's life was not only productive, but also fascinating. He began his life being one of seven kids. While undergoing his research, Galileo was ordered to be imprisoned; although the sentence was later commuted to house arrest. The church was angry with him because he believed in Copernicus’ hypothesis that the Earth revolved around the sun, also known as the Heliocentric Theory. Galileo was so important to the world of science that he is often referred to as the "father of modern astronomy," the "father of modern physics," and as the "father of science."