“Galileo was that guy whoinvented the telescope.” This is what most people say whenthey think about Galileo. However, Galileo did not eveninvent the telescope; he only made improvements to it so itcould be used for astronomy. Galileo did use it to makemany important discoveries about astronomy, though; manyof these discoveries helped to prove that the sun was thecenter of the galaxy. Galileo also made many importantcontributions to Physics; he discovered that the path of aprojectile was a parabola, that objects do not fall withspeeds proportional to their weight, and much more. Forthese discoveries, Galileo is often referred to as the founderof modern experimental science. Galileo Galilei was born inPisa, Italy on February 15, 1564.
Until he was about 10years old, Galileo lived in Pisa; in 1574 the family moved toFlorence where Galileo started his education atVallombroso, a nearby monastery. In 1581, Galileo went tothe University of Pisa to study medicine, the field his fatherwanted him to peruse.
While at the University of Pisa,Galileo discovered his interest in Physics and Mathematics;he switched his major from medicine to mathematics. In1585, he decided to leave the university without a degree topursue a job as a teacher. He spend four years looking for ajob; during this time, he tutored privately and wrote on somediscoveries that he had made. In 1589, Galileo was given thejob of professor of Mathematics at the University of Pisa.
His contract was not renewed in 1592, but received anotherjob at the University of Padua as the chair of Mathematics;his main duties were to teach Geometry and Astrology.
Galileo taught at the university for eighteen years. Galileomade many important discoveries from the time he was bornto when he left the University of Padua, 1564-1610. Whileattending the University of Pisa, 1584, Galileo discoveredthe principle of isochronism. Isochronism showed that theperiod of a pendulum remains the same no matter what theamplitude is. Galileo was said to have discovered this whilewatching a chandelier swing in the cathedral next to theLeaning Tower of Pisa. Galileo proved the isochronism of apendulum in 1602. He later used his discovery to design aclock that used pendulums. While Galileo was looking for ajob after he left the University of Pisa, 1856, he invented thehydrostatic balance. This was a device that found thespecific gravity of substances by weighing them under water.
This is what gave Galileo his first notice from the public.
Galileo also discovered that Aristotle’s belief that objects fallat velocities proportional to their weight was wrong. Hefound that all objects fall at the same rate; it is only thedensity of the median they fall through that causes largerobjects to fall slower. He believed that all objects would fallthe same rate if they were in a vacuum. It is said Galileoshowed his students at the University of Pisa his discoveryby dropping a musket ball and a cannon ball at the sametime from the Leaning Tower of Pisa. Some scientists in anarticle in New Scientist claim that Galileo was wrong insaying that all objects fall at the same rate. They base theircalculations on the quantum theory.
Particles in the objectsare constantly absorbing and releasing photons; thisabsorbing and releasing changes the total energy that theparticles carry, which depends on temperature. This thenchanges the inertial mass of the object. From this thescientists concluded that heavier and cooler objects will fallfaster than those objects that are lighter and hotter.
Althoughthis disproves what Galileo found, Galileo was still fairlycorrect in his findings; the effect these scientists found is verysmall. It is almost impossible to measure the difference in thetime it takes two objects of different weights to reach theground. (“Galileo Got it Wrong”, p. 36.) Galileo also mademany discoveries while he was teaching at the University ofPadua. Some of his little inventions were a calculatingcompass, a thermometer, and a pump. One of his biggerdiscoveries was that the path of a projectile was a parabola.
The parabola was due to the combined forces of horizontalmotion and vertical acceleration. He tested this by mountinga chute on a table and letting the ball on it fly off the edge.
He then marked the spot where the ball landed. This becamevery useful in the firing of ballisticas, guns, and rockets.
Another discovery Galileo made while he was at theUniversity of Padua was the “law of fall,” 1604. Galileoexplained the “law of fall” as “the spaces passed over innatural motion are in proportion to the squares of the time.”This is basically the acceleration of objects in a free fall.
Galileo based this law on Newton’s laws of motion. Duringhis last years at the University of Padua, Galileo heard abouta knew invention called the telescope. At Padua, he built atelescope that was 20 times as powerful as the one that wasfirst invented. Galileo used this for astronomical purposes.
During the time this telescope was built, the belief of mostpeople, including the Catholic Church, was that the Earthwas the center of the universe. This view of the universe isreferred to as the Ptolemaic system. They also believed thatall things around the earth were perfect and unchanging.
There were some people who opposed the Ptolemaicsystem; these people believed in the Copernican system.
This is where the sun is the center, rather than the sun.
Galileo believed in the Copernican system. When Galileopointed his telescope to the sky, he made many discoveriesthat confirmed the Copernican system. One thing he foundwas that the moon was not a perfect sphere as thought of inthe Ptolemaic system; it had craters and mountains notvisible to the human eye. Another discovery Galileo madewas that Jupiter had moons going around it. This conflictedwith the Ptolemaic system. It proved that the earth was notthe only planet with moons going around it. Galileo alsofound that Venus had phases just like the Moon; this meantthat it had to be orbiting the sun. He also discovered that thesun had spots on it that could be used to see how the earthorbits around it. These discoveries all contradicted thePtolemaic system and confirmed the Copernican system. In1610, Galileo started to publish his findings on theCopernican system. The first publication of his findings wasin “The Starry Messenger.” The publications of Galileo’sfindings got him in a lot of trouble with the Catholic Church.
In 1616, Galileo was summoned to Rome and band by theCatholic Church to discuss the Copernican system. Galileofollowed the rule until 1632 when he published the “DialogueConcerning the Two Chief World Systems.” This article toldGalileo’s views of why the Copernican system was betterthan the Ptolemaic system. Galileo was summoned to Romeagain and given life imprisonment under house arrest fordisobeying orders. The charge given to Galileo was veryunfair considering that he was right. In 1979, Pope John PaulII wanted the Catholic Church to reverse the condemnationof Galileo. In 1992, the Catholic Church admitted to theirerror in condemning Galileo to house arrest. Galileo did notgive up his work because he was under house arrest. Hespent much of his time writing publications of his early work.
He had to sneak his publications to Holland to be printed,though, because they were forbidden to be printed in Italy.
He wrote of Isochronism, the parabola path projectiles take,the “law of fall”, and much more. In 1637, Galileo wentblind, but he found assistants to write for him. “Discoursesupon Two New Scientists” was one of the most knownarticles that Galileo wrote during this time. Galileo alsoworked on clock that used a pendulum to run during thistime. Galileo died in early January of 1642. As you see,Galileo is much more than just a man who used aastronomical telescope. Galileo made many importantdiscoveries for the field of Physics; he opened the way forscientists to combined Mathematic and Physics. He alsoproved that the sun was the center of the galaxy. Galileo
deserved to be called the founder of modern experimentalscience. Bibliography Dunn, Travis. Galileo
Biography.
- Http:/es.rice.edu/ES/ humsoc/Galileo/index.html. 23 January1996. Field, J.V. Galileo Galilei.
- http://www-groups.dcs.st-and.ac.uk/-history/Mathematicians/Galileo.html.
- August 1995. “Galileo Got it Wrong.” New Scientist. 4 June1987, p. 36. MacKeith, Bill. “Galileo Galilei.” The ClassicalScientists. Southside Ltd. Edinburgh, England. 1989. vol.
- 15, pp. 25-44. O’Malley, Charles D. “Galileo.” The NewEncyclopedia Britannica. Encyclopedia Britannica Inc.
- Chicago, Illinois. 1989. vol. 19, pp. 640-642. Stillman,Drake. The Life of Galileo Galilei. http://www.
- owlnet.rice.edu/-jessdave/Galileo2.html. 1980. Stillman,Drake. “Galileo.” Microsoft Encarta. Copyright 1994Microsoft Corp. Copyright 1994 Funk ; Wagnalls Corp.
- Stillman, Drake. “Galileo.” The World Book Encyclopedia.
- World Book Inc. London, England. 1995. vol. 8, pp. 11-12.
- Category: History