In 1564, the year Galileo Galilei was born, Michelangelo and John Calvin both died. The Renaissance was well underway by then, and the royal courts of Europe and the Catholic church were becoming accustomed to bestowing favors upon individuals in return for deeds or cash. The Middle Ages had been marked by pestilence and famine. Now that the blights had ended, the growing reformation movement had reform in mind. Reform had already led to the killing of a leading scientist of the day. For his sin of opposing infant baptism among other heresies, Michael Servitus, astronomer, mathematician and geographer, had been burned at the stake outside the gates of Geneva in 1553. Into this changing world the father of science (alternatively the father of astronomy, the father of physics) was born.

Also Born in 1564 – William Shakespeare

Galileo was the oldest of six born to a famous lute player in Pisa, Italy. His father was a man of modest means, but he had scientific leanings, keen observation skills and, it is said, pretensions to royalty. The elder Vincenzio had designs that his boy would get a medical degree from the University of Pisa. But Galileo changed his major before graduating and by age 25 had been appointed head of the math department. Unfortunately his father died two years later. This left Galileo, ten years older than any of his siblings, the head of household. To meet a family obligation to pay a dowry incurred by the marriage of his sister, Galileo soon accepted a position at the University of Padua. He was chairman of the math department and taught geometry and astronomy. He would stay at Padua for 18 years, giving classes on the side in surveying, cosmography and optics while trying out one entrepreneurial venture and another. He wasn't always working though. Galileo sired three children in Padua by his housekeeper, Marina di Andrea Gamba.

Crimes of Passion

Though he was a Roman Catholic, Galileo apparently suffered no penalty for having children out of wedlock. The two girls did. They were put into San Matteo convent in Arcetri while still children. One was sickly and died very young. The other took the name Maria Celeste when she took the veil. Despite her tenure at the impoverished convent she was Galileo's favored child. Galileo conducted household repairs at the convent personally, and Maria Celeste was a constant advocate for him and a devoted, loving correspondent. Galileo's son Vincenzio was pronounced legitimate post-partum by order of the Grand Duke of Tuscany and grew up to become a lute player like his grandfather.

By 1610 Galileo's lectures and tutoring had become very popular in Padua. The school offered him tenure, but Galileo was disappointed with the benefits package. Soon afterwards, he was offered a lifetime appointment as "Chief Mathematician of the University of Pisa and Philosopher and Mathematician to the Grand Duke." The Grand Duke of Tuscany, that is. The royal patronage was what Galileo wanted. He moved back to Pisa. Several years later his son joined him there, while his mother Maria Gamba stayed in Padua and finally married a local boy.

The Work

Beginning as an undergraduate Galileo had begun to notice some of the physical phenomena that were precursors to his more important discoveries. He realized that the duration of a pendulum’s swing remains the same no matter how far it swings. Eventually this resulted in the invention of pendulum clocks and for medicine, a means of taking an accurate pulse. That means was a pocket-sized device designed and sold by Galileo. He recognized that the path of a projectile is parabolic. He applied his new science by inventing the 'sector,' a compass-like device inscribed with slide-rule like markings for measuring the elevation of a cannon and therefore adjusting the trajectory of the projectiles with a greater accuracy than in the past. He sold sectors in his classes with accompanying documentation, and tutored his students in their use. He hit upon his law of falling bodies in 1606, proving its validity mathematically three years later. He invented and patented a horse-drawn water pump and a primitive sort of thermometer. He studied and codified hydrostatics, which could be called no-velocity fluid dynamics, or the mathematics of water-pressure standing at rest in a tank.

The Controversy

Though Galileo was never called to task by the brain police for his off-duty passions with his housekeeper, he suffered from other sorts of legal trouble. When he heard that a 'new star' had become visible he observed the event carefully. He was actually observing a supernova. His observations and calculations by triangulation proved that the supernova was further away than the moon (it still is) and therefore must necessarily be in the Heavens. He delivered three public lectures asserting that the Heavens are not static and permanent. Things change there, too. Johannes Kepler in Prague was reaching the same conclusion. The proof, unfortunately, flew directly in the face of papal wisdom.

As fate would have it in late 1608, and with the heightened interest in the Heavens following the worldwide observation of the supernova, Hans Lipperhey in the Netherlands had applied for a patent for a 3x telescope, calling it a 'device for seeing things far away as if they were near.' It was a simple apparatus. By the following year many people were making them. Galileo made a 20x model and began observing and mapping the moon. Soon after, in the spring of 1609, Galileo saw three little moons moving around the behemoth that is Jupiter. He wrote some academic works describing his work in detail. Soon afterward, he found a fourth moon of Jupiter and traveled to Rome to let scholars see them for themselves.

Showdown

Since that time a total of 63 moons of Jupiter have been observed, but the idea that Jupiter is a planet orbiting the sun just like Earth, with its own moons just like Earth, was a challenge to a status quo unaccustomed to being challenged. At that point the previous cosmologies of Aristotle and Ptolemy, asserting God’s Green Earth as the center of the universe, had been acceptable reality for over 1000 years.

The upshot was that within four years after his discovery, a schism had occurred. Clergy had begun condemning the heliocentric views of Galileo, Copernicus and Kepler from the pulpit. The controversy grew and grew even while Galileo continued his work. He invented the microscope. And carefully, while trying not to offend the sensibilities of the papacy, he continued to write on astronomy. He discovered the rings of Saturn, sunspots, and craters on the moon, all suggestions to a critical eye that he was asserting the universe to be something other than perfect. He attempted to calculate the speed of light but failed due to inadequate instruments. More than all of these, he practiced a scientific method that demanded rigorous, objective observation.

The Inquisitors

In 1616 he was admonished by a Cardinal Bellarmine for his dangerous teachings. The cardinal had recently ordered heliocentrist scholar Giordano Bruno burned at the stake for heresy. Galileo kept a low profile for a while after that, always sure to keep his arguments hypothetical. In 1630 he went to the mats. He had an advocate in the new Pope Urban, and he was given permission to write a book. But his book Dialogue Concerning Two Chief World Systems upset the Vatican. He had been ordered to present both points of view. He did not. Further, his portrayal of the position of Pope Urban on the subject was generally seen as unflattering. He was summoned to Rome by the Inquisition and charged with heresy.

By 1633 he was convicted. Though the church never took issue directly with validity of heliocentrism, it demanded he recant his position that the sun is the center of the solar system. It banned his book and placed him under arrest. Fortunately for him, his arrest was of a more genteel type than experienced by most victims of the inquisition. He became the houseguest of the Archbishop of Siena, a supporter and friend, and six months later was allowed to move to a villa in Arcetri, near the convent where his daughter lived.

There he lived until his death in early 1642, writing a treatise on motion and acceleration called Dialogue Concerning Two New Sciences and otherwise publishing from his remaining notes. Wisely, he had his remaining works published in the Netherlands.

Referring principally to his last book, both Albert Einstein and Stephen Hawking called Galileo the most important natural scientist that ever lived.

NaSPA member Jim Rue writes about computers and conducts training and field service in Orange
County, CA. He can be reached at Jim [at] NFWriter [dot] com.