Galileo Galilei (1564-1642) was an Italian astronomer, physicist, and engineer. He is often referred to as the "father of observational astronomy," the "father of modern physics," and the "father of the scientific method." He made pioneering observations of nature with long-lasting implications for the study of physics. Galileo improved the telescope, allowing him to make significant discoveries such as the four largest moons of Jupiter (now known as the Galilean moons), the phases of Venus, and detailed observations of sunspots and the lunar surface. His support for heliocentrism (the idea that the Earth orbits the Sun) brought him into conflict with the Roman Catholic Church, leading to his trial and house arrest. Despite his challenges, Galileo's work laid the foundation for modern science and influenced future scientists like Isaac Newton. He was born on February 15, 1564, in Pisa, Italy, He passed away on January 8, 1642, in Arcetri, near Florence.