Galileo Galilei was a famous Italian astronomer, engineer, physicist, philosopher and mathematician who lived between 1564 and 1642. He advocated many advances in science and astronomy and played a key role in the Scientific Revolution. Later in life he was sentenced to house arrest by the Holy Office and wrote one of his best works "Discourses and Mathematical Demonstrations Relating to Two New Sciences."
One of Galileo's first inventions was the ancestor of the thermometer named the thermoscope. When he wrote a book on his invention of a hydrostatic balance, he gained the notice of the scientific world. Galileo went on to write the book "On Motion," in which he stipulates that in a vacuum, objects fall with equal momentum regardless of density. He went on to invent and patent a pump model, and then invented the telescope.
Using his telescope, Galileo identified four of Jupiter's moons, noticed sunspots and watched a supernova. Based on his observations, he validated the Copernican claim that the Earth orbits the sun. The subsequent publishing of the book, "Dialogue Concerning the Two Chief World Systems" in which he elaborated on the Copernican theory, led to his permanent house arrest in his house near Florence.
Pope John Paul II acknowledged in 1992 that Galileo's trial was unjust, and the Holy Office made a mistake. A plan to build a statue of Galileo on the Vatican grounds was proposed, and then suspended. Albert Einstein has named Galileo "the father of modern science."