The Copernican Revolution


The 16th Century was a time of tremendous upheaval for it marked major changes in the world of scientific and religious thinking. Martin Luther led the Protestant Reformation with his 95 theses and the Diet of Wurms defense of this thinking in 1517 and 1519. Since this event marks the opening of the door to scientific thinking as well as a split from the Church by a large number of people, you are now asked to learn more about the details of Martin Luther's life and how his writings affected the people as much as did the writings of Copernicus, Galileo, and Newton. If you have not already done so, please click on Martin Luther to learn about the Reformation and how the writings of Luther may have spurred Copernicus to share his new ideas of the solar system with the general public.


Nicolaus Copernicus - the first real challenge to the Ptolemaic theory came in 1543, with the publication of a book by Polish churchman Mikolaj Kopernik, better known by his Latinized name of Nicolaus Copernicus. His main objection to the geocentric, or earth-centered, theory was its clumsiness. He recognized that many of the complications could be removed by putting the sun in the central place of the system and allowing everything to revolve around it. In this he was correct, but he was still convinced that all celestial orbits must be perfectly circular, and he was even reduced to bringing back epicycles. To see a nice set of images and text regarding the proposed heliocentric model of Copernicus, click on his image at the left. To learn more details about his life, click on Copernicus and go to his biographical account. I apologize that some of the weblinks in the biography no longer operate, but the site is still worth the visit. Within this course, I have highlighted the heliocentric model and will propose my ideas about the importance of his great intellectual leap upon all of science and mankind ever since.

Nicolaus Copernicus accomplished much in his thinking of the motions of the planets, more so than he expected. At the left is his ideas of how planets revolved around the sun. He worked out a detailed theory of the moon in orbit and set the distance of the moon at about 60 times the earth's radius - a figure close to what we use today.
He noted that the moon's orbit was not an earth-centered circle.
He concluded that the earth was definitely a planet.
Whereas Ptolemy argued against the idea of a rotating earth because the mountains would be ripped from their roots, Copernicus argued more forcefully that such a rotation would have an even great effect on the sky which has a larger radius. Since neither happened, why not at least look at the earth's rotation as causing the sun to appear to orbit the earth.
Copernicus was the first to recognize that Polaris does not stay in the same position because the axis of the earth slowly wobbles.
He justified his conclusions: "... in the midst of all stands the sun. For who could in this most beautiful temple place this lamp in another or better place than that from which it can at the same time illuminate the whole? Which some not unsuitably call the light of the world, others the soul or ruler. Trismegistus calls it the visible God, the Electra of Sophocles, the all-seeing. So indeed does the sun, sitting on the royal throne, steer the revolving family of stars." By no means did Copernicus desire to remove God from the Universe. To him, God could more accurately occupy the central place in creation, with man revolving around God. The Sun would be the embodiment of the eternal, all-powerful, and light and life-giving God.
Essentially, Copernicus desired to bring about a harmony of the natural world, created by God, and the spiritual world, described by God in the Bible. Furthermore, as seen to the left, God created everything with perfection, and thus all orbital paths were perfect circles, even as they were in the drawings of Ptolemy.

Copernicus was well aware that his ideas would offend the Church; to regard the Earth as anything but supreme would be to invite a charge of heresy. Prudently, he withheld publication of his book until he was dying in 1543, even though he developed his theory in 1507. His little book was entitled "de Revolutionibus" and the cover page appears to the right of this text.

It has always be difficult for my students to grasp the importance of Copernicus' work as well as his personal struggle with sharing his ideas with the public. One needs only look at the history of the Church to see the origins of this struggle. Nicolaus Copernicus was a devout Catholic. To pronounce a heliocentric model would most certainly mean his excommunication, and the prospect of eternal death and damnation were a chance he refused to take. For almost 1400 years, the European world had accepted the geocentric model of Ptolemy. As mentioned earlier in the history discussion, this model satisfied the observations of people, their personal philosophy of self-centeredness, the religious convictions as espoused in the Judeo-Christian Bible, as well as the sheer complexity of the mathematics and epicycle motions.

Copernicus reasoned that all of the motions that he observed in the sky could be accounted for with a sun-centered system, and without the necessity of complicated epicycle motions. He realized, however, that his views would stir up controversy and perhaps mean trouble for him from the Church. Being raised by Church leaders, Copernicus wished to offend no one, so he withheld publication of his treatise until near his death.

His fears were well-founded, as some later Copernicans found to their cost: one of them, Giordano Bruno, was burned at the stake in Rome in 1600. (This was only one of Bruno's crimes in the eyes of the church, but it certainly was a serious one.) Finally, Copernicus' book was placed on the Papal Index, where it remained until 1835. Nicolaus Copernicus was the individual who developed a heliocentric model of the solar system and took the chance of sharing his ideas publicly. While the tiny book was quickly banned for public reading through an edict of the Pope, there were a few curious minds who found the heliocentric idea of great interest. To see how the Copernican model was proven correct, move on to the page which tells a remarkable story of an egocentric astronomer named Tycho Brahe.

Or you can return to the Introduction to the History Unit, Martin Luther, the Syllabus, or the Home page.


| Home | Course Information | Assignments | Teacher Bio | Course Units | Syllabus | Links |