Europe in the sixteenthcentury was faced with a large scientific dilemma: Should they continue tofollow what they know or open up their minds to a new possibility?Specifically, referring to the two competing astronomical systems and theoriesof Claudius Ptolemy (100AD – 170AD) and Nicolaus Copernicus (1473 – 1543). ThePtolemaic model, at its time, offered a more complicated and abstract solarsystem compared to its Greek predecessors. Ptolemy’s model was composed insecond century A.D. and purposed that “each planet orbited in an epicycle,essentially a small circle, centered on a point in its orbit around the Earth,or even on a point in another epicycle” (Ferris 24). The Ptolemaic universe was essentiallygeocentric (Earth-centered) and was widely accepted for centuries.
It was notuntil Copernicus published On theRevolutions of the Heavenly Spheres in 1542, did the Ptolemaic geocentricuniverse become challenged. The model of the solar system proposed by Copernicus was not morecomplicated than that of Ptolemy’s, but actually more simple. While thePtolemaic solar system was geocentric, the Copernicus model was heliocentric.
Copernicus’heliocentric model entailed that the solar system did not actually revolvearound the Earth, but revolved around the Sun. Copernicus therefore placed anon-moving Sun in the middle, wherein the Earth and the other planets wouldrotate around it (Townley 119). Advantageously, compared to the Ptolemaic system the Copernican model wassimple, as it did not rely on epicycles. It as well provided a natural explanationof the motions of the planet and the seasons; propositioned a much betterobservable account on the brightness of the planets; and, relatively predictsthe accurate position of the planets to the sun (Galilei 334). All around, theCopernican model gave a more accurate representation of the planetary systemsthan that of the older Ptolemaic model.
These are just a few of the many ways the Copernicanmodel differed and was more proactive than the Ptolemaic model. Although the Copernican model offered up a fresh perspective, it likemany theoretical observations, had its disadvantages. For one, the Copernicanmodel was not any more accurate than the Ptolemaic model, since it “portrayedthe planets as orbiting the sun in perfect circles, it was driven towardcomplexity and error” (Ferris 25). Today, it is recognized that the planetary orbits are not in factcircular like Copernican believed, but elliptical (oval). However, this can notbe solely attributed to Copernicus’ incompetency, but rather due to the factthat physics at the time had not advanced much since the Greeks (Ferris25).
Consequently,the largest disadvantage of the Copernican model was not fundamentally due tothe actual theory, but because of the political and social disturbance itcaused. The Ptolemaic model was recognized as scientific truth for numerouscenturies and was widely accepted by the Church. As well, the Copernican model was not essentially “new”, but areiteration of a similar Greek philosopher. However, his model garnered a widerfollowing than that of the Greek philosopher’s, whose idea was once rejected,due to the shift in the intellectual climate of sixteenth-century Europe. The introduction of the Copernican model in thesixteenth century was a turning point for Astronomy and came at the perfect time. Going back to therelease of the printing press in 1440, there had already begun a huge shiftwithin the intellectual sphere as wide-spread access of information beganpossible.
At the time, the Ptolemaic model had been studied for more than athousand years and his theories had been tiredly tried over and over again. There-emergence of the heliocentric model coupled with the intellectualreformation and Copernicus’ prestige, allowed for a wider acceptance of the newschool of thought. The rising Copernican model was favoured by youngerastronomers and scholars on a “radical bent, not because it solved all theirproblems, but because…it opened up fresh prospects for original thought” (Ferris 25). To these astronomers, the Ptolemaic model had become outdated and small,while the Copernican model offered the possibility of much more.
Although itwas accepted by the more progressive astronomers, it was viciously rejected bythe Church. The Ptolemaic system was geocentric, which meant it placed theEarth in the center of the solar system. This model was very much accepted bythe church as it followed the stories written within the Bible. During thesixteenth century, the Church and religion still held much power within theintellectual spheres. If scientific notions, such as the Copernicus model, didnot match the Holy Scriptures, that would mean those who agreed would be underminingthe word of the Bible and ultimately, going against God and challenging thepolitical position of the Church. For that reason, the heliocentric model couldnever be considered legitimate in the eyes of the Church. However, the Churchdid not express any formal opinion or opposition until the Galileo Galilei(1564 – 1642) affair (Finocchiaro 108).
TheGalileo affair brought the idea of Copernicus’ heliocentric model back intomotion. In 1610, Galileo published his work StarryMessenger, which contradicted thefindings of previous Greek philosopher, Aristotle (Finocchiaro 27). It is within this work where Galileo’s observationselevated Copernicus’s idea. He answers the age old question on why jumper’s donot land westward. He found that Aristotle’s theory of “inertia” is not “just atendency of bodies at rest to remain at rest, but also bodies in motion remainin motion” (Ferris 29). Thus, begins Galileo’sbattle with the Church, as he tries to force the Copernican model uponthem. In order to neutralize the Copernican model, religious authorities optedto find ways to delegitimize the heliocentric system. In February 1616, authoritiesdecided to hold a judicial procedure against Galileo.
The findings of the casefound the Copernican theory as “contrary” to Holy Scripture, thereforeinherently false. Amendments and corrections were thus made on Copernicus’ Revolutions of the Heavenly Spheres thatthe Church deemed acceptable (Finocchiaro33). The Church also desired for Galileo to abandonthe idea of the heliocentric model as a possible scientific “fact”, but rather,would allow him to continue studying as long as it stayed simply a”hypothesis.” In order to neutralize the possible break from the Ptolemaicmodel to the Copernican model, the Church exercised its political and social power.Anyone who followed Galileo and the heliocentric model was then labelled a”sinner” or “going against God” by the Church. Thus, anyone who publicallyrecognized the heliocentric model was at risk of becoming condemned by theChurch and ostracized. Eventually,Galileo breached the 1616 rulings, when in 1632 he published Dialogue Concerning the Two Chief WorldSystems, where her publicly adopted the heliocentric system and affirmed itas reality (Finocchiaro 257).
In order to reinforce to society the power of the Church, they made anexample out of Galileo, forcing him to recant his doctrine and placed his bookon a list of prohibited works. Although the Copernican model wasnot the most accurate, it can be recognized that the notoriety of Copernicus’ workpaved the way for many scientists and astronomers. His work rejuvenated theidea of a heliocentric solar system and encouraged many people to question whatthey thought true for centuries. His work challenged the power of the Churchand created public discussion on the authenticity of the stories in the Bible. Ultimately,Copernicus’ work changed the course of astronomy.