21 Impressive Galileo Galilei Facts For Kids That Love Modern Science

Arpitha Rajendra
Jan 23, 2024 By Arpitha Rajendra
Originally Published on Jan 19, 2022
Edited by Jacob Fitzbright
Read these amazing Galileo Galilei facts here.
Age: 3-18
Read time: 10.1 Min

Galileo Galilei was able to work under the blessing of the Church for a long time.

In his early 70s, Galileo Galilei lost his eyesight completely. Currently, it is believed that the cause of blindness was either chronic glaucoma or a complicated cataract.

Galileo Galilei's full name was Galileo di Vincenzo Bonaiuti de' Galilei and was from Pisa, Italy. Galileo was born on February 15, 1564, the first child of Vincenzo Galilei, a music theorist, lutenist, and composer, and Guilia Ammannati. They had six children. Galileo was an engineer, physicist, and astronomer and sometimes referred to as a polymath. He studied the principle of relativity, free fall, gravity, velocity, speed, projectile motion, and inertia. He also worked on hydrostatic balances, properties of pendulums, and applied science and technology. Galileo Galilei invented several military compasses and thermoscopes and made use of the telescope to observe celestial bodies, scientifically. He observed Jupiter's four largest moons, rings of Saturn, confirmed the phases of Venus, and analyzed sunspots. Although he considered taking up the priesthood, Galileo enrolled for a medical degree at the University of Pisa in 1580 due to insistence from Galileo's father. Ealy works of Galileo Galilei on scientific instrument description includes 'La Billancetta' or 'The Little Balance' in 1586 and 'Le Operazioni del Compasso Geometrico et Militare' in 1606.

Galileo Galilei Life History

Galileo's family moved to Florence when he was eight years old, however, for two years, Muzio Tedaldi took care of him. He moved to Florence to live with his family when he was 10. He was particularly educated in logic in Vallombros Abbey between 1575-1578. Galileo Galilei usually only referred to himself by the given name. Both his family and given name were derived from his ancestor, vital professor, politician, and physician of France called Galileo Bonaiuti. Young Galileo kept away from studying mathematics because a physician earned a lot more than a mathematician did. He later attended a geometry lecture accidentally, after which he talked to his father to not only let him study mathematics but also natural philosophy rather than medicine.

  • As a music teacher, Galileo's dad taught him to play the lute and this sense of music might have helped Galileo in his scientific works.
  • Galileo Galilei had three children with Marina Gamba out of wedlock. Virginia (daughter) was born in 1600, Livia (daughter) was born in 1601, and Vincenzo (son).
  • Due to financial concerns, Galileo Galilei left the University of Pisa in 1585.
  • Galileo Galilei found his life mission and got many followers working at the University of Padua and also gave lectures.
  • His two daughters joined Arcetri's San Matteo convent, where they become nuns and stayed there until their death.
  • Some astronomers and the Roman Catholic church opposed Galileo's work on the daily rotation of the Earth and revolution around the sun, or the Copernican system.
  • The Roman inquisition concluded that Galileo's Copernican theory was, indeed, correct.
  • In 1632, the Catholic church trial presided by Pope Urban VIII found Galileo Galilei to be 'vehemently suspect of heresy', sentencing him to life in prison and placing him under house arrest.
  • Pope John Paul II initiated the investigation on Galileo's condemnation by the Catholic Church in 1979.
  • The Catholic Church closed the investigation on this matter in 1992, officially apologizing. This statement blamed the clerks who worked on Galileo's case except for Pope Urban VIII.
  • Galileo Galilei died in 1642 at the age of 77 due to heart palpitations and fever. He was buried in Basilica di Santa Croce, next to his dad and other ancestors. His daughter, Virginia, is also buried in Santa Croce.
  • In the year that Galileo Galilei died, another famous scientist, Isaac Newton was born.
  • Galileo Galilei showed appreciation for the accurate relationship between theoretical physics, experimental physics, and mathematics.
  • Giovanni Demisiani, a Greek mathematician coined the term 'telescope' for Galileo's instrument in 1611 at a banquet held by Prince Federico Cesi for making Galileo Galilei a member of the Accademia dei Lincei.

Galileo Galilei Greatest Inventions

The scholarly world first got to know about Galileo Galilei when he made the forerunner of a thermometer, a thermoscope, and then published the hydrostatic balance design book, in 1586. Galileo studied 'disegno', a word that included fine arts. He got the role of an instructor at the Academy of the Arts of Drawing or Academia Delle Arti Disegno of Florence and taught chiaroscuro and perspective. He was selected to lead mathematics in Pisa in 1589. In 1604, Galileo observed Kepler's Supernova. He then concluded that Supernova was a distant star. Based on the ambiguous descriptions of Hans Lippershey's first practical telescope that he first tried to patent in 1608, Galileo created a telescope that had three times magnification. He again updated this version up to 30 times more magnification.

  • Astronomical investigations and discoveries on the Copernican heliocentrism led to Galileo's lasting legacy including the grouping of the four moons of the planet Jupiter as the Galilean moons.
  • The four moons or Galilean moons are named Ganymede, Lo, Europa, and Callisto. He first named the moons of Jupiter as 'three fixed stars'.
  • Galileo Galilei went on to name these fixed stars as Medicean stars, honoring the Grand Duke of Tuscany, Cosimo II de Medici, and his three brothers.
  • The first of Galileo's telescopes were built in the year 1609.
  • Galileo Galilei invented Sector, which was an instrument that helped with the calculation of division, multiplication, trigonometry, and proportion problems. It was used until the 19th century.
  • Galileo Galilei discovered a principle of how liquid density changes with temperature. The Galileo thermometer also works on the same principle.
  • Galileo spent years experimenting on magnetic declination, arming of magnets, and magnetic needles.
  • Galileo Galilei was not the first man to observe the night sky using a telescope, but it was an Englishman named Thomas Harriot. However, Galileo additionally made conclusions on his observations.
  • The moons of Jupiter discovered by Galileo Galilei were the first moons known to mankind that orbited around a planet other than our own planet.
  • The earliest design of escapement mechanism in a pendulum clock was created by Galileo Galilei when he was totally blind.
  • It was previously said that the cause of blindness in Galileo Galilei was the long observations of the sun using his telescope while he was spotting sunspots. However, this was proved to be false later.
  • The invention of the military compass to aim at cannonballs is also credited to Galileo.
  • Galileo Galilei was the first human being to discover that Milky Way was made of stars.
  • Galileo Galilei opposed the theory of Kepler, which stated that the Moon was the reason for tides on our planet and instead stated that our planet's rotation caused tides.
  • Kepler also showed support for Galileo's work by publishing letters.
  • Due to the narrow field of view, Galileo Galilei could only see half the moon's width through his telescope.
  • As per legends, Galileo Galilei started his studies on the moving pendulum when he was at the Cathedral of Pisa, after looking at the lamp that swung back and forth. However, he was not successful in building a working pendulum clock.
  • Galileo Galilei was one of the first modern scientists to agree to the fact that all laws of nature are mathematical.
  • His inventions also led towards the separation of religion and philosophy from science, which was the greatest development that would influence human thought in the future.
Galileo Galilei made the first contributions to the science of motion by the innovative combination of mathematics and experiments.

Galileo Galilei Famous Quotes

Galileo Galilei contributed a lot to the scientific community. He observed many celestial objects of the solar system. Galileo was first to infer that the uneven waning on our moon was light occlusion caused by craters and lunar mountains. Galileo's observations of Jupiter's moons created a revolution in the field of astronomy. In 1611, he continuously observed satellites for 18 months and gave a remarkably precise estimation of their periods. Galileo observed Venus from September of 1610 and noted that this planet exhibited phases identical to that of our Moon. He then observed Saturn, however, he first thought that Saturn's rings were a planet. In 1612, Galileo Galilei observed Neptune. He also studied sunspots with his naked eye and his telescope. Some of his famous quotes include:

  • 'You can't teach anybody anything, only make them realize the answer's already inside them.'
  • I have never met a man so ignorant that I couldn't learn something from him.'
  • 'All truths are easy to understand once they are discovered, the point is to discover them.'
  • 'The laws of nature are written by the hand of God in the language of mathematics.'
  • 'In the sciences, the authority of thousands of opinions is not worth as much as one tiny spark of reason in an individual man.'
  • 'To understand the universe, you must understand the language in which it is written, the language of mathematics.'
  • 'I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use.'
  • 'Knowing thyself, that is the greatest wisdom.'
  • 'Two truths cannot contradict one another.'
  • 'To be humane, we must ever be ready to pronounce that wise, ingenious, and modest statement 'I do not know.''
  • 'Although it does move... And yet it moves.'
  • 'The Milky Way is nothing else but a mass of innumerable stars planted together in clusters.'
  • 'I have loved the stars too fondly to be fearful of the night.'
  • 'Thought is the most pleasing ability gifted to humankind.'
  • 'The sun with all those planets revolving around it and dependent on it can still ripen a bunch of grapes as if it had nothing else in the universe to do.'
  • 'The prohibition of science would be contrary to the Bible, which in hundreds of places teaches us how the greatness and the glory of God shine forth marvelously in all His works and is to be read above all in the open books of the heavens.'

Galileo Galilei Books

Galileo wrote mainly about the description of scientific instruments. In the last years of Galileo's life, he kept around 598 volumes at the Villa il Gioiello, Florence. Although he was restricted to writing and publishing his ideas, he received visitors until his death, and through them he constant supply of Nothern Europe's lastest research. Two of his visitors under house arrest were Thomas Hobbes, the philosopher, and poet John Milton. His early written works on mechanics, the science of motion, and dynamics were recorded in his Le Meccaniche circa 1600 and De Motu circa 1590. It is believed that Galileo dropped two balls of different masses but the same material from the leaning tower of Pisa to demonstrate how the time of descent was independent of the mass of an object. However, Galileo Galilei himself did not include this incident in any of his works.

  • Galileo's 'Sidereus Nuncius', or 'The Starry Messenger', published in 1610 was the first-ever scientific written work based on telescopic observations to be published.
  • 'The Starry Messenger' consisted of the roughness of the surface of our Moon, Galilean Moons, variations between the appearance of fixed stars and planets, and the existence of many stars that were not visible to our naked eyes.
  • In 1613, Galileo Galilei published 'Letters on Sunspots' that consisted of descriptions of sunspots.
  • Some of his other works include 'Discourse of the Comets', 'Discourse on the Tides', and 'The Assayer'.
  • His objective lenses and two telescopes are still kept in a museum in Itay.
  • During Galileo's time under house arrest, Galileo Galilei wrote 'Two New Sciences' in 1638.
  • The church banned the book 'Dialogue Concerning the Two Cheif World Systems' written by Galileo Galilei at that time. This ban was only lifted by the church after 200 years in 1835.
  • The favorite scientist of Albert Einstein was Galileo Galilei. Albert Einstein also stated that Galileo's works marked the true beginning of physics.
  • The principle called Galileo's relativity or Galileo's invariance, stating that laws of motion do not change in any inertial frame became central to the special theory of relativity by Einstein and foundation for the Newton's laws of motion.
  • Bertolt Brecht, a German playwright made a popular play known as 'Life of Galileo'.
  • An unmanned spacecraft called 'Galileo' was launched by America in memory of this famous astronomer. This spacecraft was sent to study Jupiter and its Galilean moons.
  • 'Galileo' was also the name of the global satellite system developed by Europe for civil navigation.

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Written by Arpitha Rajendra

Bachelor of Engineering specializing in Aeronautical/Aerospace Technology, Master of Business Administration specializing in Management

Arpitha Rajendra picture

Arpitha RajendraBachelor of Engineering specializing in Aeronautical/Aerospace Technology, Master of Business Administration specializing in Management

With a background in Aeronautical Engineering and practical experience in various technical areas, Arpitha is a valuable member of the Kidadl content writing team. She did her Bachelor's degree in Engineering, specializing in Aeronautical Engineering, at Nitte Meenakshi Institute of Technology in 2020. Arpitha has honed her skills through her work with leading companies in Bangalore, where she contributed to several noteworthy projects, including the development of high-performance aircraft using morphing technology and the analysis of crack propagation using Abaqus XFEM.

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