Italian astronomer and experimental philosopher was born at Pisa on Feb. 15, 1564. he came of a noble but impoverished Florentine Family; his father Vincenzio Galilei was a competent mathematician and an able musician. Galileo received his early education at the monastery of Vallombrosa, near Florence. Here he studied Greek, Latin and logic but showed distaste for the science he was taught. He acquired a reputation for intellectual aptitude as well as for mechanical invention. In 1581 his father sent him to the University of Pisa to study medicine.
Galileo was a skillful musician and showed a taste for painting. He was endowed with many natural gifts. In 1581 while watching lamp set swinging in the cathedral of Pisa, he observed that, whatever the range of its oscillations, they were invariably executed in equal times. The experimental verification of this fact led him to the important discovery of the isochronisms of the pendulum. He applied the new principle to the timing of the human pulse.
Up to this time he was entirely ignorant of mathematics, Accident, however happens and a lesson in geometry which he overheard by chance awakened his interest and with his father’s reluctant permission he began to study mathematics and science.
In 1585 he withdraw from the university, through lack of means, before he had taken a degree, and returned to Florence. He lectured to the Florentine academy and in 1586 he published an essay descriptive of his invention of the hydrostatic balance, which rapidly made his name known throughout Italy.
During this he wrote a treatise, in 1588, on the centre of gravity in solids, at the request of his first patron, the Marches Guildubaldo, a man of science. Because of this treatise he obtained post of mathematical lecture at the Pisan University.
During the ensuing two years (1589-91) he carried on that remarkable series of experiment by which he established the first principles of dynamics. He showed that path of projectile is a parabola. His sarcasm roused the anger of men holding different views. He became unpopular, resigned his professorship and withdraw to Florence in 1591.
Galileo seems at an early period of his life, to have adopted the Copernican theory of the solar system, but wad deterred from avowing his opinions by the fear of ridicule. A amour of invention of telescope which reached Venice in June 1609, sufficed to set Galileo on the track to produce a telescope of power of 32. He began to make observation with telescope and the Sidera Medicea in 1610.
Galileo observed the mountainous configuration of the moon and he showed that the Milky way was a collection of lesser stars. An important discovery was that of Jupiter satellites first seen by Galileo on Jan 7, 1610. This was strong confirmation of Copernican theory. Later he observed what happened to him as the triple or of Saturn the phase of Venus and sun spots.
In Sept. 1610 Galileo finally abandoned Padua for Florence. His researches with telescope had been rewarded by venetain senta with the appointment for life to his professorship at a high salary. He was also appointed as philosopher to grand duke of Tuscany.
In 1611 Galileo visited Rome and exhibited the telescopic wonder of heavens to the eminent personage at the pontifical court. In 1612 he published a book which refused Aristotle’s ideas and supported Archimedes’ principle. Galileo’s brilliant researchers enhanced by his formidable dialectic zeal drew the attention of authorities to the discrepancies between the new view of the solar system and certain passage in the Scriptures.
He had no desire to raise the theological issue. Not only did Galileo explain adverse texts but he tired to produce scriptural confirmation of the of the Copernican system. The agitation against him increased and in 1615 he received a semi-official warning to avoid theology and limit himself to physical reasoning.
In Feb. 1616 the consulting theologians of the Holy Office characterized the proposition that sun is immovable in the centre of the world and that earth has diurnal motion of rotation as heretical. Shortly afterwards Galileo was admonished by the Pop Paul V, not to hold, teach or defend the condemned doctrine. The injunction he promised to obey.
Galileo returned to Florence and for seven years he led of a life of to studious retirement at Bellosguardo but at the end he appeared in public with his “Saggiatore” in which he dealt with the nature of comets. It had passages containing a defense of Copernican theory and was received with acclamation by ecclesiastical no less than by scientific authorities.
He set himself to complete his book and finished it in June 1630. “Dialogo die due massimi sistemi del mondo” was published in 1932. It was concerned with two chief world systems. It was not astronomical, on attack of an ancient idea of earth. A trumult of applause from every part of Europe followed its publication.
Towards the end the sale was prohibition. He pleaded his age and health but no excuse was admitted. On June 21 he was finally examined by inquisition and on following day Galileo was sentenced to incarceration. He was ordered to recite once a weak fore three years the seven penitential psalms.
Galileo remain in custody of inquisition from 21st of June. On July 6 he was permitted to leave for Siena. He spent several months with archbishop Ascanio Piccolomini.
On his return to Florence his prodigious mental activity continued to last. In 1637 his last discovery that of moon’s diurnal and monthly liberations was made, only a few months before he became blind. He continued his scientific researches and later he was engaged in dictating to his disciple. He was seized with the slow fever which resulted his death in Jan. 8, 1642.