Galileo Galilei
Galileo, who made significant contributions to the field of mathematics and the acceptance of a now heliocentric based solar system is widely regarded as the “Father of Modern Science”. (Portrait of Galileo (1636) by Justus Sustermans/Wikipedia)
A Starry Realization
“All truths are easy to understand once they are discovered; the point is to discover them”
On a starry night in Padua, Northern Italy 400 years ago, one man first turned a telescope to the sky, and discovered something absolutely outrageous; something alarming; something phenomenal and purely delightful.
The Sun, the man, hypothesized: “remains fixed in the centre of the circle of heavenly bodies, without changing its place; and the Earth, turning upon itself, moves around the Sun.”
A fascinating idea, but one that faced harsh rejection from very fierce authorities of the time: the Catholic Church. Outraged by theories that a sun-centred, or Copernican heliocentric based solar system could exist, the church viewed such ideas as impossible, making their intentions clear: that if he continued to promote heretical ideas and not leave them be, he would be sentenced to indefinite imprisonment.
Keen on exploration, and knowing it to be “impossible to deceive the laws of nature,” such threats did not stop the man from seeking truth, and fighting against impossible ideas: impossible ideas so deceiving and nefarious that they would, in time, revolutionize the foundations of astronomy, and pave the way for a new, and modern, view of the solar system forever.
But, who came up with these astounding ideas, and how were they inspired?
Galileo Figaro Magnifico
In 1564, Galileo Galilei, a famous Italian astronomer, mathematician, and inventor was born in Florence as the oldest son to Vincenzo Galilei, a musician who made important contributions to the theory and practice of music.
Finding meaning in the theory and practice of things himself, Galileo took over his father’s work in his own way by making fundamental contributions to the sciences of motion, astronomy and strength of materials.
Armed with prodigious intelligence and drive, he became fascinated with many subjects, and in 1583 enrolled at the University of Pisa, where he studied medicine. While at Pisa, Galileo was exposed to the Aristotelian view of the world, then the leading scientific authority and the only one sanctioned by the Roman Catholic Church.
Supporting the Aristotelian view like other intellectuals of the time, Galileo was en route to become a university professor. With financial difficulties holding him back, however, he left the university in 1585 before he could even earn his degree.
His study of mathematics continued past his leaving the university, and he continued to support himself with minor teaching positions. In this time, he also began a two-decade study on objects in motion and published The Little Balance which described the hydrostatic principles of weighing small quantities. This brought him some fame, and earned him a teaching post at his own alma mater in 1589.
His time at the University of Pisa was short-lived and his contract ended in 1592, presumably due to his creation of a manuscript entitled De Motu (On Motion), which disputed the Aristotelian views of motion and falling objects. This left Galileo open to criticism and, isolated from his colleagues where he, subsequently, found a new position at University of Padua. In his 18-year tenure at Padua, he gave lectures and attracted large crowds of followers, further increasing his fame and his sense of mission.
Scanning The Heavens
Determined to learn and extend his knowledge further, in the summer of 1609 Galileo developed an eye for using lenses after he learned about a simple telescope built by Dutch eyeglass makers. Curious, he soon built one of his own using concave and convex lenses and repositioning them in such a way that the telescope refracted light through a spherical lens to form an image.
With the telescope built, albeit via a trial and error process, in the fall of 1609 Galileo made a fateful decision to turn his eye toward the heavens.
Two of Galileo's first telescopes; in the Institute and Museum of the History of Science, Florence. (Encyclopedia Brittanica)
Using this new instrument - which became later known as the Galileo telescope or the first prototype of the refractory telescope - to explore the universe, Galileo observed the moon and found planets like Venus had phases like the moon, and proved that Venus rotated around the sun. Witnessing these discoveries, and finding that “questions of science, the authority of a thousand [were] not worth the humble reasoning of a single individual,” he afterwards made his rejection of the popular Aristotelian doctrine very clear. In 1632, he published one his most important works, Dialogue Concerning the Two Chief World Systems.
Dialogues followed a discussion among three people: one who supports Copernicus' heliocentric theory of the universe, one who argues against it, and one who is impartial. Though Galileo claimed his work was neutral, it was not, and the advocate of the Aristotelian doctrine that the Earth is the centre of the universe came across as a simpleton, getting caught in his own arguments.
Heresy And Fame
With Dialogues published, the church’s reaction to the works, advocating for a Copernican theory, was swift, and Galileo was summoned to Rome to hold trial.
Cardinal Maffeo Barberini, who was elected as Pope Urban VIII, and was a personal friend of Galileo’s, normally allowed Galileo to pursue his work on astronomy and even encouraged him to publish it, under the condition that it be objective and not advocate Copernican theory. Galileo objected and advocated the theory regardless, noting that: “It is harmful to souls to make it a heresy to believe what is proved.” Under trial, for the first time, he was allegedly treated with respect and never imprisoned. However, in order to make an example of him and obtain a confession, Galileo was threatened with torture, and he finally admitted he had supported Copernican theory, and privately held that his statements were correct. He was convicted of heresy and spent his remaining years under house arrest.
Ordered not to have any visitors nor have any of his works printed outside of Italy, he ignored both. In 1634, a French translation of his study of forces and their effects on matter was published, and a year later, copies of the Dialogue were published in Holland.
A few years later, his health had begun to fail, but he managed to write Two New Sciences which was subsequently published in Holland in 1638 before he died in 1642.
Though he faced immense resistance, the church, nearly a century after his death, couldn’t deny the truth in science and lifted the ban on works supporting Copernican theory. It wasn't until 1835 that the Vatican dropped its opposition to heliocentrism altogether.
Galileo's contribution to our understanding of the universe was significant not only for his discoveries, but for the methods he developed and how he used maths to prove them. He played a major role in the Scientific Revolution, and is also credited with developing major breakthroughs, including a universal law of acceleration, as well as modern day thermometers; thermometers which are based on his understanding of falling objects where, as liquid rises and falls in a glass tube, temperature of the liquid rises or falls as well. Since his death, he has earned the title as “The Father of Modern Science.”