Galileo Galilei (1564-1642) Galileo Galilei was born near Pisa, Italy, on February 15, 1564 (Drake). Galileo was the first child of Vincezio Galiei, a merchant and a musician (Jaki 289). In 1574, Galileos family moved from Pisa to Florence, where Galileo started his formal education (Jaki 289). Seven years latter, in 1581, Galileo entered the University of Pisa as a medical student (Drake). In 1583, home on vacation from medical school, Galileo began to study mathematics and physical sciences (Jaki 289).
A Family friend and professor at the Academy of Design, Ostilio Ricci, worked on translating some of Archimedes, which Galileo read and became interested in. This is where Galileo got his deep interest in Archimedes (Jaki 289). When returning to medical school, medical school became less appealing to Galileo, and his deep interests in Archimedes and mathematics drew him in, Galileo left without a degree in 1584 (Drake). Starting his studies, in 1585, in Aristotelian physics and cosmology, Galileo had to leave the University of Pisa before he got his degree, because of financial problems (Jaki 289).
Going back to Florence, Galileo spent three unsuccessful years looking for a teaching position (Jaki 289). During this time Galileo was increasing his understanding of physics and mathematics. Also during this hard time Galileo wrote two discourses one about principles of balancing and the other about center of gravity of different solid objects (Jaki 289). These writings were circulated in manuscript form only, but they made Galileo well known in the scientific community.
Galileo became renowned in 1588, when he gave a lecture at the Florentine Academy on the topography of Dantes Inferno, where he showed his extensive knowledge on mathematics and geometry (Jaki 289). In 1589, Galileos rising reputation as a mathematician and natural philosopher (physicist), earned him a teaching spot at the University of Pisa (Jaki 289). Galileo spent three years at the University of Pisa. This move changed his concepts of physics in two ways.
The first way was when he was at the university he was exposed to the writings of Fiovanni Battista Benedetti, which got his ideas from 14th century scientist Jean Buridan and Nicole Oresme at the University of Paris (Jaki 289). These writing made him break away from Aristotelian physics and start his own route through physical theories. The second part was when Galileo started teaching he argued and hated the fact that teachers had to wear academic robes while teaching. He would accept wearing ordinary clothes, but he rather that it would be the best to be naked (Jaki 289).
In 1591, Galileos father died and he had the burden to take care of his mother, brothers, and sisters (Jaki 289). Looking for a better position to support his family, Galileo found one in the University of Padua, part of the Venetian Republic (Jaki 289). There according to him he spent the happiest eighteen-years of his life (Jaki 289). He often visited Venice and made many influential friend, among them Giovanfrancesco Sagredo, whom he later immortalized in the Dialogue as the representative of judiciousness and good sense (Jaki 289). In 1604, Galileo publicly declared that he was a believer of the famous astronomer Copernicus (Jaki 290).
In three public lectures given in Venice, before an overflow audience, he argued that the new star which appeared earlier that year was major evidence in support of the doctrine of Copernicus. (Actually the new star merely proved that there was something seriously wrong with the Aristotelian doctrine of the heavens) (Jaki 290). More important was the letter Galileo wrote that year to Father Paolo Sarpi, in which he stated that the distance covered in natural motion are proportional to the squares of time intervals, and there fore, the distances covered in equal time are as the odd numbers beginning from one (Jaki 290).
What he proposed was the law of free fall, later written as s = (gt2), where s is the distance, t is time, and g is the acceleration due to gravity at sea level (Jaki 290). In 1606, he published a small booklet, The Operations of the Geometrical and Military Compass (Jaki 290). He defended that he move to University of Padua and said it was because of personal reasons (Jaki 290). In 1609, a Dutch spectacle maker, Hans Lippershey, combined two lenses and made a refracting telescope (Evans). Galileo reading about Hans Lippershey discovery made a telescope, which became the first telescope for astronomical purposes (Evans).
He submitted the invention to the Venetian Senate and the telescope was a success. This invention secured him a life long contract at the University of Padua (Jaki 290). With the new invention of the telescope Galileo was able to see 40x (Jaki 290). This enables Galileo to observe the mountains on the moon and the moons of Jupiter. For four year Galileo observed the planets, moons and stars, and he published his work in a book called Sidereus nuncios (Jaki 290). During this time Galileo was very selfish when he was publishing his work. Galileo wanted to be the sole contributor to modern physics and astronomy.
Dedicated in his work he left behind his common-law wife, Marina Gamba, and his young son, Vincenzio, and placed his two daughters in the convent of S. Matteo in Arcetri. Moving back to Florence he published Discourse on Bodies in Water, which told about the discovery phases of Venus and the most important fact it proved Copernican theory (Jaki 290). In 1616, as a result of proving Copernicus theory the church got mad at Galileo and called him before the inquisition (Jaki 290). The inquisition pardoned Galileo because Galileo was a loyal Catholic who remained loyal throughout this entire ordeal.
The Cardinal who help Galileo though the ordeal latter became Pope Urban VIII (Jaki 290). Galileo spent the next six years writing the book Dialogue concerning the Two Chief World Systems (Jaki 291). It had four parts to it relating to the earth and the moon. The first part was the universe is not perfect like the surface of the moon is rough. Second, was explanation of celestial phenomena. Third, was the debate of the earth going around the sun and was explained by the moving of the stars and that the earth moved in two way and it didnt affect the earth.
And forth, the tides prove the earths two ways of motion (Jaki 291). In 1632, the Dialogue caused Galileo to be brought before inquisition for the second time because of his belief and teaching of Copernicus doctrine (Jaki 291). This time the inquisition didnt have the sympathy for Galileo as they had the last time. Falsely proving his theories were wrong, the inquisition forced him to revert what he said or not only he but also his family will be harmed. Submitting to the inquisition Galileo was let go. While leaving the room his said Eppursi muove (And yet it does move) (Jaki 291).
Galileo went back to his professorship at the University of Padua. There his did work that did conflict with the church doctrines, mostly dealing with physics not cosmology (Jaki 292). The published his work a book similar Two New Sciences. It had four parts to it. First, were the mechanical resistance of metals and the atomic constitution of matter. Second, was the properties of lever is mathematics. Third and forth, was the analysis of projectile motion. Galileo spent his last years partially blind and died on January 8, 1642 (Jaki 292).
Jaki, Stanley L. Galileo. Encyclopedia of World Biography. 1973 ed. Drake, Stillman. Galileo Galilei. 1999 Grolier Multimedia Encyclopedia. Grolier Interactive Inc. 1998. Evans, David S. Telescope, optical. 1999 Grolier Multimedia Encyclopedia. Grolier Interactive Inc. 1998.