454 years of the birth of Galileo Galilei.
The physicist and astronomer Galileo Galilei propitiated the scientific revolution that took place during the Renaissance.
If there is an emblematic character in the history of astronomy, that is Galileo Galilei. He was born on February 15, 1564, in Pisa (then part of the Duchy of Florence), Italy.
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He studied at the Camaldolese monastery in Vallombrosa, seriously considering the priesthood, but urged by his father he entered the University of Pisa in 1581, where he intended to study medicine. Soon he left medicine because he realized that his true vocation was in mathematics and philosophy, where he demonstrated the error that Aristotle had made in stating that the speed of falling bodies was proportional to his weight, dropping from the Leaning tower of this city two objects of different weights.
Galileo never came to build a pendulum clock that worked properly.
In 1592, he moved to the University of Padua to be admitted to the chair of mathematics, and where he taught geometry, mechanics, and astronomy until 1610. There he invented the compass of calculation to solve practical problems of mathematics.
From speculative physics he went on to precise measurements, discovering the laws of the fall of bodies and the parabolic trajectory of projectiles, he dedicated himself to study the pendulum movement and investigated the mechanics and resistance of materials. He left aside astronomy, although from 1595 he was inclined to the theory of Copernicus, which claimed that the Earth revolved around the Sun.
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In 1609 he presented to the Duke of Venice a telescope of a power very similar to binocular binoculars. With his twenty-magnification telescope he discovered mountains and craters on the Moon, he could see that the Milky Way was composed of stars and discovered the four largest satellites of Jupiter. A few months later he published The Messenger of the Stars, a book in which he spoke these discoveries.
In his last years of life, he lost his sight, so he hired an apprentice to help him write and carry out his experiments.
In December of 1610, he saw the phases of Venus, which went totally against the astronomy of Ptolemy and confirmed his acceptance of the theories of Copernicus. It was criticized by professors of philosophy since Aristotle had claimed that in heaven there could only be perfectly spherical bodies and that it was not possible for anything new to appear.
Many scientists discussed the findings and theories of Italian, because they contradicted those that had coined Aristotle, and at that time, to question what he said, was a heresy.
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What was Galileo Galilei's sin? Defend the heliocentric model of Nicolaus Copernicus, which proposed that the Earth and the planets revolve around the Sun; therefore, ridiculed geocentrism, which placed the Earth at the center of the Universe, an idea that was based on Aristotelian physics.
He was one of the pioneers in studying the Milky Way, so he discovered that it was not a nebula, but a group of stars.
In 1612 Although the Catholic Church was reluctant to his ideas, he left it to publish the book Dialogue on the two highest systems of the world, text in which he confirmed the heliocentric model. Even so, the Inquisition called him to appear in Rome, in a trial for grave suspicions of heresy.
It was April 12, 1633, when the Italian scientist was 69 years old, he showed up for his appointment before the Holy Office. Because of his ideas, he was sentenced to life in prison. But on June 22, 1633, Galileo was forced to pronounce on his knees the abjuration of his doctrine before the commission of inquisitors, under the orders of Pope Urban VIII, who had been his friend.
He was forced to say "I Galileo Galilei abandoned the false opinion that the Sun is the center and is motionless. I abjure, curse and detest such errors " when he stood up after this imposed argument, he muttered:" E pur si muove "(And yet he moves), referring to the Earth around the Sun.
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His sentence was commuted and he was sentenced to live under house arrest. But that was not all punishment because he was also ordered to burn all copies of his book and his sentence had to be read publicly in the universities. His last work was Considerations and mathematical demonstrations on two new sciences, published in Leiden in 1638.
In reality, Galileo was not the inventor of the telescope. This instrument was invented in 1608, in the Netherlands. The astronomer only improved it by adding more powerful lenses.
Galileo died on January 8, 1642, at age 77, in Florence. The Grand Duke of Tuscany, Ferdinand II, wanted to be buried in the main body of the Basilica of Santa Croce, next to the tombs of his father and other ancestors, and to erect a marble mausoleum in his honor. These plans were annulled by Pope Urban VIII and his nephew, Cardinal Francesco Barberini, protesting that Galileo had been accused by the Catholic Church of "heresy". He was buried in a small room next to the novices' chapel at the end of a corridor from the southern transept of the sacristy basilica. His remains were buried in the main body of the basilica in 1737 in a monument erected in his honor.
Among his works we have:
- 1586 - The bilancetta.
- 1590 - De motu.
- 1606 - Operazioni del compasso geometrico et militare.
- 1600 - Le meccaniche.
- 1610 - Sidereus nuncius.
- 1615 - Letter to the Grand Duchess Cristina.
- 1616 - Discorso del flusso e reflusso del mare.
- 1619 - Discorso delle comete.
- 1623 - Il saggiatore.
- 1632 - Dialog sopra i due massimi sistemi of the toledo and Copernican mondo.
- 1638 - Discorsi e dimostrazioni matematiche, intorno a due nuove scienze attenenti alla meccanica & i movimenti locali.
Among his innumerable quotations, these five can be selected as a synthesis of his thought and legacy.
"Mathematics is the language with which God has written the universe."
"Where the senses fail us, reason must intervene".
"Know yourself, that is the greatest wisdom".
"Both the Sacred Scriptures and nature come from the divine Word, truths can not contradict one another."
"God is known by nature in his works and by the doctrine in his revealed word".
For more information visit:
- https://www.biography.com/people/galileo-9305220
- https://en.wikipedia.org/wiki/Galileo_Galilei
- https://www.britannica.com/biography/Galileo-Galilei
- http://www.bbc.co.uk/history/historic_figures/galilei_galileo.shtml
excellent ... I'll follow you every day and vote for you all ... do the same.
I recommend the excellent play by Bertold Brecht: Life of Galileo