An Italian physicist, mathematician, astronomer, and philosopher, Galileo Galilee is best known for his major role in the Scientific Revolution. An ardent supporter of Copernicanism, he brought about great improvements in the telescope as well as the consequent astronomical observations. His is also credited with discovery of the four largest satellites of Jupiter (named Galilean moons), and the observation and analysis of sunspots. For his contributions to the world of science and astronomy, he is often known as 'Father of Modern Observational Astronomy', 'Father of Modern Physics', 'Father of Science' and 'Father of Modern Science'.

Early Life & Education
Galileo Galilee was born in Pisa, Italy, on February 15, 1564. He was the first of six children of Vincenzo Galilei, a famous lutenist and music theorist, and his wife Giulia Ammannati. Although Galileo's father was a musician and wool trader, he wanted his visibly talented son to study medicine. So, at the age of eleven, Galileo was sent off to study in a Jesuit monastery. After four years, Galileo announced to his father that he wanted to be a monk. Following this, he was hastily withdrawn from the monastery.

In 1581, when he was 17 years old, Galileo entered the University of Pisa, to study medicine, as his father wished. There, he got attracted to mathematics. He even started taking private instruction in math from Ostilio Ricci, and progressed rapidly. Galileo left the University in 1585 without a degree and returned to Florence to study Archimedes and Euclid. He supported himself by teaching mathematics in Florence and Siena.

Career
In 1589, Galileo became a professor of mathematics at Pisa. In 1592, Galileo's contract at Pisa ended and was not renewed. However, he got the chair of mathematics in Padua, where he remained for 8 years. There, he started teaching geometry, mechanics, and astronomy. He remained at the university until 1610. During this period, Galileo made significant discoveries in both pure science and applied science. The great scholar also made huge advances and enhanced his reputation.

Experiments With Science and Mathematics
Through experiments, Galileo proved that light hits the ground at exactly the same time as the heavy weight. Galileo continued to be interested in how things fall. Galileo found that when things fall they don't move at a constant speed, but they accelerate, or get constantly faster. He found a new rule. The distance traveled when you are falling is proportional not to the time, but to the square of the time. He experimented and worked out a rule for pendulums. The time of the swing is not proportional to the length of the pendulum, but the time is squared.

Telescope And Astronomic Discoveries
In 1609, Galileo heard about the invention of the spyglass, a device that made distant objects appear closer. Galileo used his mathematics knowledge and technical skills to improve upon the spyglass and build a telescope. Later that same year, he became the first person to look at the Moon through a telescope and make his first astronomy discovery. He subsequently used his newly invented telescope to discover four of the moons circling Jupiter, study Saturn, observe the phases of Venus, and study sunspots on the Sun.

Galileo's observations strengthened his belief in Copernicus' theory that Earth and all other planets revolve around the Sun. After Galileo began publishing papers about his astronomic discoveries and his belief in a heliocentric or Sun-centered Universe, he was called to Rome to answer charges brought against him by the Inquisition (the legal body of the Catholic Church). Early in 1616, Galileo was accused of being a heretic, a person who opposed Church teachings. Galileo was cleared of charges of heresy, but was told that he should no longer publicly state his belief that Earth moved around the Sun.

Imprisonment & Death
Galileo continued his study of astronomy and became more and more convinced that all planets revolved around the Sun. In 1632, he published a book that stated, among other things, that the heliocentric theory of Copernicus was correct. Galileo was once again called before the Inquisition and this time was found guilty of heresy. He was sentenced to life imprisonment in 1633. Because of his age and poor health, he was allowed to serve his imprisonment under house arrest. Finally, he left for the holy abode on January 8, 1642.