The Heliocentric Theory of Nicolaus Copernicus
Considered one of the most significant astronomical thinkers of all time, Nicolaus Copernicus forever changed the way scientists understand the design of our solar system. His suggestion of a heliocentric model of the universe challenged the widely held belief that the Earth was at rest in the center of the universe, with the sun and other planets revolving around it.
The proposition of Copernicus’ cosmological beliefs sparked controversy in both scientific and religious communities, and his ideas were generally disregarded. However, within roughly one hundred and fifty years, the work of other planetary scholars such as Kepler, Galileo, and Newton eradicated any disbelief and put Copernicus’ original ideas into fruition.1
Born in 1473 in Poland into an affluent family, Copernicus was granted access to an education at the Jagiellonian University where he enrolled in various courses of mathematics, astronomy and astrology.2 As Copernicus developed an interest in these subjects, he also began to study Greek. This was a turning point in his education, as an understanding of Greek was essential in his exploration of the work of Plato.3
The world inhabited by Copernicus was one completely engulfed in change. The Italian Renaissance, which had spread its way into Europe by the time of Copernicus’ birth, set the stage for an era of revolutionary new ideas and methods of thinking.
In the year 1492, the discovery of the New World initiated a frenzy of excitement for scientists who now knew the world was round instead of flat. This concept alone is imperative to Copernicus’ celestial studies, for an understanding of Earth itself was essential to his exploration of the heavens.
Between the years 1503 and 1513 it is believed that Copernicus developed his heliocentric (sun-centered) model of our galaxy.4 In the first report of his astronomical observations referred to as the Commentariolus, Copernicus begins by explaining the mathematical issues he discovered in the Ptolemaic model:
Yet the planetary theories of Ptolemy and most other astronomers, although consistent with the numerical data, seemed likewise to present no small difficulty. For these theories were not adequate unless certain equants were also conceived; it then appeared that a planet moved with uniform velocity neither on its deferent (main orbit) nor about the center of its epicycle (second orbit) … Having become aware of these defects, I often considered whether there could perhaps be found a more reasonable arrangement of circles, from which every apparent inequality would be derived and in which everything would move uniformly about its proper center, as the rule of absolute motion requires.5
In essence, Copernicus was expressing his confusion and concern about the mathematical background of Ptolemy’s system; which, through his intense observations and research, he was able to correct to the best of his ability by developing his sun-centered model of the universe.
Copernicus’ heliocentric model of the galaxy can be summarized into five main points:
- The earth revolves around the sun along with the other planets, instead of the sun revolving around the earth.
- The moon is the only celestial object that revolves around the earth.
- The earth completes one full rotation on its axis every day, giving us daytime and nighttime.
- Other planets’ revolutions around the sun take significantly longer than the earth.
- The universe is actually overwhelmingly larger than it was originally believed to be.6
At this time in Europe, there was an inherent truth held by society in the field of astronomy. Ptolemy’s geocentric model of the galaxy had been in place for thousands of years. The Catholic Church had also adopted this belief, as an earth-centered design of the galaxy helped justify the importance of mankind in relation to God and the scripture. In the prelude to his book, Copernicus’ Secret: How the Scientific Revolution Began, author Jack Repcheck explains:
The Church had long embraced the (geocentric model) because it conformed to scripture and placed humans at the center of God’s firmament. Copernicus’ revolutionary work not only presented an entirely different cosmology, but once accepted, it required a titanic shift in mind-set and belief. No longer the center of God’s creation, the earth became just one of the other planets. By extension, the primary position of God’s highest creation, humankind, was also diminished.
These ideas were all expressed in much greater detail in the Commentariolus .
With this in mind, it is important to understand that Copernicus was in no way attempting to demean the teachings of the Church. In addition to his intellectual pursuit, Copernicus was also a canon in the Church and was required to take a vow of celibacy.7
Unfortunately for the Church, the emerging ideas of the Scientific Revolution were coupled with the attacks of the Protestant Reformation. Martin Luther’s seemingly simple act of nailing his 95 theses on the door of a church sparked the beginning of an increasingly defensive religious authority. The Church, which had been cashing in on its sale of Indulgences, was now facing serious scrutiny by many who believed this practice was fundamentally wrong in terms of how a church should truly act. These accusations placed the Church in a vulnerable position, and in turn the Church chose to place new scientific theories under a metaphorical microscope in the hopes of degrading any possible truth that might go against the biblical teachings.
Copernicus continued to publish his discoveries in various texts. His next compilation was titled On the Revolutions of Heavenly Orbs. In this text, Copernicus explores in depth the mathematical calculations necessary to back up his theory. Inserted into the Revolutions was an unsigned preface by the Protestant scholar Andreas Osiander. In summary, this preface stated:
…that (Copernicus’) heliocentric model was in the tradition of mathematical astronomy, where truth was of little account compared to the calculatory function of the model. This deflected religious criticism, but clearly it did not represent the mind of Copernicus. He thought his system was the actual system of the world: it was truth, not an algorithm.8
Copernicus’ work, now referred to largely as the Copernican Revolution, can be considered the beginning of modern astronomy. His in-depth research was groundbreaking for his time, and the publication of his discoveries during this time placed him in the center of religious scrutiny and strained his relationship with the Church. Although his death came before his ideas could be celebrated as true, his enduring reputation as “the father of modern astronomy and catalyst of the scientific revolution”9 will live on forever.
1 Matthews, Michael R., ed., The Scientific Background to Modern Philosophy (Indianapolis, Hackett Publishing Company, 1989), 35.
2 Repcheck, Jack. Copernicus’ Secret: How the Scientific Revolution Began (New York, Simon & Schuster, 2007), 26.
3 Matthews, The Scientific Background, 33.
4 Repcheck, Copernicus’ Secret, 52.
5 Ibid., 54.
6 Ibid., 55
7 Ibid., 3.
8 Matthews, The Scientific Background, 35.
9 Repcheck, Copernicus’ Secret, 2.