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Nicolaus Copernicus: Against The Ptolemaic System The cosmology of early 16th-century Europe held that Earth sat stationary and motionless at the center of several rotating, concentric spheres that bore the celestial bodies: the sun, the moon, the known planets, and the stars.
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It is true that astrology required that medical students acquire some grounding in astronomy; nevertheless, it is likely that Copernicus studied astrology while at the University of Padua.
Copernicus did not receive his medical degree from Padua; the degree would have taken three years, and Copernicus had only been granted a two-year leave of absence by his chapter. Instead he matriculated in the University of Ferrara, from which he obtained a doctorate in canon law. But he did not return to his chapter in Frombork; rather he went to live with his uncle in the episcopal palace in Lidzbark-Warminski Heilsberg in German.
Although he made some astronomical observations, he was immersed in church politics, and after his elderly uncle became ill in , Copernicus was his attending physician. Rosen , —35 reasonably conjectured that the bishop may have hoped that his nephew would be his successor, but Copernicus left his uncle because his duties in Lidzbark-Warminski interfered with his continuing pursuit of his studies in astronomy.
He took up residence in his chapter of Frombork in and stayed there the rest of his life. Not that leaving his uncle and moving to Frombork exempted Copernicus from continued involvement in administrative and political duties. He was responsible for the administration of various holdings, which involved heading the provisioning fund, adjudicating disputes, attending meetings, and keeping accounts and records.
In response to the problem he found with the local currency, he drafted an essay on coinage MW — in which he deplored the debasement of the currency and made recommendations for reform. His manuscripts were consulted by the leaders of both Prussia and Poland in their attempts to stabilize the currency. He was a leader for West Prussia in the war against the Teutonic Knights, which lasted from — He was physician for the bishop his uncle had died in and members of the chapter, and he was consulting physician for notables in East and West Prussia.
Nevertheless, Copernicus began to work on astronomy on his own. Sometime between and he wrote an essay that has come to be known as the Commentariolus MW 75— that introduced his new cosmological idea, the heliocentric universe, and he sent copies to various astronomers. He continued making astronomical observations whenever he could, hampered by the poor position for observations in Frombork and his many pressing responsibilities as canon.
Nevertheless, he kept working on his manuscript of On the Revolutions. In a young mathematician named Georg Joachim Rheticus — from the University of Wittenberg came to study with Copernicus. Rheticus brought Copernicus books in mathematics, in part to show Copernicus the quality of printing that was available in the German-speaking cities.
Most importantly, he convinced Copernicus to publish On the Revolutions. Rheticus oversaw most of the printing of the book, and on 24 May Copernicus held a copy of the finished work on his deathbed. Classical astronomy followed principles established by Aristotle.
Aristotle accepted the idea that there were four physical elements — earth, water, air, and fire. He put the earth in the center of the universe and contended that these elements were below the moon, which was the closest celestial body.
There were seven planets, or wandering stars, because they had a course through the zodiac in addition to traveling around the earth: the moon, Mercury, Venus, the sun, Mars, Jupiter. Beyond that were the fixed stars. But observers realized that the heavenly bodies did not move as Aristotle postulated. The earth was not the true center of the orbits and the motion was not uniform. And in an age without professional astronomers, let alone the telescope, Ptolemy did a good job plotting the courses of the heavenly bodies.
Not all Greek astronomical ideas followed this geocentric system. Pythagoreans suggested that the earth moved around a central fire not the sun. Archimedes wrote that Aristarchus of Samos actually proposed that the earth rotated daily and revolved around the sun. During the European Middle Ages, the Islamic world was the center of astronomical thought and activity.
In addition, Ragep, , has shown that a theory for the inner planets presented by Regiomontanus that enabled Copernicus to convert the planets to eccentric models had been developed by the fifteenth-century, Samarqand-trained astronomer ali Qushji — Renaissance humanism did not necessarily promote natural philosophy, but its emphasis on mastery of classical languages and texts had the side effect of promoting the sciences.
He noted that Ptolemy showed the moon to be at various times twice as far from the earth as at other times, which should make the moon appear twice as big. It is impossible to date when Copernicus first began to espouse the heliocentric theory.
Had he done so during his lecture in Rome, such a radical theory would have occasioned comment, but there was none, so it is likely that he adopted this theory after His first heliocentric writing was his Commentariolus. It was a small manuscript that was circulated but never printed. Thus, Copernicus probably adopted the heliocentric theory sometime between and It is impossible to know exactly why Copernicus began to espouse the heliocentric cosmology.
Despite his importance in the history of philosophy, there is a paucity of primary sources on Copernicus. Sadly, the biography by Rheticus, which should have provided scholars with an enormous amount of information, has been lost. Goddu —84 has plausibly maintained that while the initial motivation for Copernicus was dissatisfaction with the equant, that dissatisfaction may have impelled him to observe other violations of uniform circular motion, and those observations, not the rejection of the equant by itself, led to the heliocentric theory.
Blumenberg has pointed out that the mobility of the earth may have been reinforced by the similarity of its spherical shape to those of the heavenly bodies. As the rejection of the equant suggests a return to the Aristotelian demand for true uniform circular motion of the heavenly bodies, it is unlikely that Copernicus adopted the heliocentric model because philosophies popular among Renaissance humanists like Neoplatonism and Hermetism compelled him in that direction.
Most importantly, we should bear in mind what Swerdlow and Neugebauer 59 asserted:. In the Commentariolus Copernicus listed assumptions that he believed solved the problems of ancient astronomy.
Although the Copernican model maintained epicycles moving along the deferrent, which explained retrograde motion in the Ptolemaic model, Copernicus correctly explained that the retrograde motion of the planets was only apparent not real, and its appearance was due to the fact that the observers were not at rest in the center.
The work dealt very briefly with the order of the planets Mercury, Venus, earth, Mars, Jupiter, and Saturn, the only planets that could be observed with the naked eye , the triple motion of the earth the daily rotation, the annual revolution of its center, and the annual revolution of its inclination that causes the sun to seem to be in motion, the motions of the equinoxes, the revolution of the moon around the earth, and the revolution of the five planets around the sun.
In a sense it was an announcement of the greater work that Copernicus had begun. He received some discouragement because the heliocentric system seemed to disagree with the Bible, but mostly he was encouraged.
Fear of the reaction of ecclesiastical authorities was probably the least of the reasons why he delayed publishing his book. His administrative duties certainly interfered with both the research and the writing. His revolutionary ideas in the field of astronomy were embodied in his work De revolutionibus orbium coelestium On the revolutions of the celestial spheres Written in , but decided not to publish it until a few months before his death, which occurred in May In this work can be found much of the contributions of Copernicus in physics and astronomy, although the impact of this character is not limited to these fields of knowledge.
The most recognized and revolutionary contribution of Nicholas Copernicus is undoubtedly the theory of heliocentrism. Up to this point, Ptolemy's model had been followed, which proposed that the earth was the center of the universe Geocentrism. Copernicus proposed a model of a spherical universe, in which both the Earth and the planets and stars revolved around the Sun.
This contribution of Copernicus to science is perhaps the most revolutionary in the history of mankind, A paradigm shift for the sciences. And it is that from that moment, the science began to be based on observations and mathematical measurements, and is not beliefs and simple theoretical affirmations.
The rise of the Greek Renaissance came to Copernicus early, and in Bologna he began to learn it in He translated into Latin the letters of the seventh-century Byzantine philosopher Theophilus of Simocatta, printed in , This is your only previous publication to De revolutionibus orbium coelestium.
It is important to note that Copernicus' acquisition of a good reading level was critical for his studies in astronomy, since most of the works of Greek astronomers, including Ptolemy, had not yet been translated into Latin, the Which were written. Moreover, it is noteworthy that this knowledge of Greek allowed him to reinterpret Aristotle.
The fact that the center of the universe was the earth implied that the center of gravity of the universe was the earth; And this could be corroborated with the physical phenomena that occurred here. If the center of gravity is no longer the earth, why then do things within the earth fall to its center? Copernicus's response to this was one of his great contributions to the world of science:.
All matter has gravity, and the heavy matter will attract and be attracted by similarly heavy matter, just as the smaller matter will be attracted to the larger matter.
In this way, the small things that are on the earth, are attracted to the earth. For example, the moon, being smaller than the earth, revolves around it, and the earth, being smaller than the sun, does the same.
Copernicus helped in the revision of the Julian calendar, which was the official calendar since the fourth century. Pope Leo X asked the astronomer to participate in the reform that took place between and Nicholas Copernicus was based on his heliocentric model of the universe to solve the problems presented by the previous calendar, but it was not until the year that all the changes came into effect in the Gregorian calendar.
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