Galileo Galilei was an astronomer, mathematician and physicist.

He was born at Pisa, Italy in 1564. He was born of an lower class Italian nobility and financially less well off. His father was hoping he will be a merchant but realized his intelligence. Galileo, was sent to study medicine at Pisa. He couldn't get a scholarship. Galileo showed them that a pendulum of any length would swing at a constant frequency but it was to no avail and he left without a degree.

From there on he experimented at home. He invented a hydrostatic balance and wrote an article on it. This scientific paper got him a place as a lecturer in mathematics at Pisa. Then he moved to Padua and became the chairman of mathematics in 1592.

He spent 18 years there and laid the foundation of science of moving bodies - dynamics.

Galileo also worked with the telescope which was invented in 1608 by a Dutch spectacles-maker and Galileo altered it to a higher quality a year later.

Galileo's first discovery was that there were four moons of Jupiter. This discovery was controversial to the belief that the Universe revolves round the earth. He published a paper on his findings and left Padua in 1610.

He then became a philosopher and mathematician to Cosimo II deMedici, the Duke of Tuscany. Galileo found the Sun's spot and issued a publication on that, An observation of Galileo told us about the oval shape of Saturn, and that the Venus moves round the Sun.

Galileo was born 20 years after Nicholas Copernicus who stated that the Earth was a planet and moves round the Sun, not the centre God's universe. Galileo believed in that theory and spent his life in fear of ridicule and of public menace.

Nicholas Copernicus, Galileo and Johannes Keppler laid the foundation for Isaac Newton's laws of motion.

He eventually was provoked into writing an open letter and with that got into confrontation with the Church. In 1616 the Pope denounced Copernicus and Galileo was forbidden to teach the new science.

Till 1832 Galileo never published anything. Then he wrote 'Dialoque on the Two Great Systems of the World', which got him into trouble with Rome. At an Inquisition in Rome he was sentenced to house arrest; his health deteriorated and he became blind, Galileo died in 1642.