thought experiment of nicolaus copernicus

• History Classics
• Your Profile
• Find History on Facebook (Opens in a new window)
• Find History on Twitter (Opens in a new window)
• Find History on YouTube (Opens in a new window)
• Find History on Instagram (Opens in a new window)
• Find History on TikTok (Opens in a new window)
• This Day In History
• History Podcasts
• History Vault

Nicolaus Copernicus

By: History.com Editors

Updated: January 31, 2023 | Original: November 9, 2009

Nicolaus Copernicus was a Polish astronomer and mathematician known as the father of modern astronomy. He was the first European scientist to propose that Earth and other planets revolve around the sun, the heliocentric theory of the solar system. Prior to the publication of his major astronomical work, “On the Revolutions of the Heavenly Spheres,” in 1543, European astronomers argued that Earth lay at the center of the universe, the view also held by most ancient philosophers. In addition to correctly postulating the order of the known planets from the sun and estimating their orbital periods relatively accurately, Copernicus argued that Earth turned daily on its axis and that gradual shifts of this axis accounted for the changing seasons.

Who Was Copernicus?

Nicolaus Copernicus was born on February 19, 1473 in Torun, a city in north-central Poland on the Vistula River. Copernicus was born into a family of well-to-do merchants, and after his father’s death, his uncle–soon to be a bishop–took the boy under his wing. He was given the best education of the day and bred for a career in canon (church) law.

At the University of Krakow (today’s Jagiellonian University ), he studied liberal arts, including astronomy and astrology, and then, like many Europeans of his social class, was sent to Italy to study medicine and law.

While studying at the University of Bologna , he lived for a time in the home of Domenico Maria de Novara, the principal astronomer at the university. Astronomy and astrology were at the time closely related and equally regarded, and Novara had the responsibility of issuing astrological prognostications for Bologna.

Copernicus sometimes assisted him in his observations, and Novara exposed him to criticisms both of astrology and of aspects of the Ptolemaic system — founded by the ancient mathematician and astronomer Ptolemy — which placed Earth at the center of the universe.

Copernicus later studied at the University of Padua and in 1503 received a doctorate in canon law from the University of Ferrara . He returned to Poland, where he became a church administrator and doctor.

In his free time, he dedicated himself to scholarly pursuits, which sometimes included astronomical work. By 1514, his reputation as a learned mathematician, physician and astronomer was such that he was consulted on matters of currency and coinage, and by church leaders attempting to reform the Julian calendar .

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.

From ancient times, philosophers adhered to the belief that the heavens were arranged in circles (which by definition are perfectly round), causing confusion among astronomers who recorded the often eccentric motion of the planets, which sometimes appeared to halt in their orbit of Earth and move retrograde across the sky.

In the second century, Ptolemy sought to resolve this problem by arguing that the sun, planets, and moon move in small circles around much larger circles that revolve around Earth. These small circles he called epicycles, and by incorporating numerous epicycles rotating at varying speeds he made his celestial system correspond with most astronomical observations on record.

The Ptolemaic system remained Europe’s accepted cosmology for more than 1,000 years, but by Copernicus’ day accumulated astronomical evidence had thrown some of his theories into confusion. Astronomers disagreed on the order of the planets from Earth, and it was this problem that Copernicus addressed at the beginning of the 16th century.

Heliocentric Theory

Sometime between 1508 and 1514, Copernicus wrote a short astronomical treatise commonly called the Commentariolus, or “Little Commentary,” which laid the basis for his sun-centered or heliocentric theory, a radical departure from the conventional wisdom of his era. The work was not published in his lifetime.

In the treatise, he correctly postulated the order of the known planets, including Earth, from the sun, and estimated their orbital periods relatively accurately.

For Copernicus, his heliocentric theory was by no means a watershed, for it created as many problems as it solved. For instance, heavy objects were always assumed to fall to the ground because Earth was the center of the universe. Why would they do so in a sun-centered system?

He retained the ancient belief that circles governed the heavens, but his evidence showed that even in a sun-centered universe the planets and stars did not revolve around the sun in perfectly circular orbits.

Because of these problems and others, Copernicus delayed publication of his major astronomical work, De revolutionibus orbium coelestium libri vi, or “On the Revolutions of the Heavenly Spheres,” nearly all his life. Completed around 1530, it was not published until 1543 — the year of his death.

What Did Nicolaus Copernicus Discover?

In “On the Revolutions of the Heavenly Spheres,” Copernicus’ groundbreaking argument that Earth and the planets revolve around the sun led him to make a number of other major astronomical discoveries. While revolving around the sun, Earth, he argued, spins on its axis daily. Earth takes one year to orbit the sun and during this time wobbles gradually on its axis, which accounts for the precession of the equinoxes.

Major flaws in the work include his concept of the sun as the center of the whole universe, not just the solar system, and his failure to grasp the reality of elliptical orbits, which forced him to incorporate numerous epicycles into his system, as did Ptolemy. With no concept of gravity, Earth and the planets still revolved around the sun on giant transparent spheres.

In his dedication to “On the Revolutions of the Heavenly Spheres”–an extremely dense scientific work–Copernicus noted that “mathematics is written for mathematicians.” If the work were more accessible, many would have objected to its non-biblical and hence heretical concept of the universe.

For decades, “On the Revolutions of the Heavenly Spheres” remained unknown to all but the most sophisticated astronomers, and most of these men, while admiring some of Copernicus’ arguments, rejected his heliocentric basis.

Death and Legacy

Nicolaus Copernicus died on May 24, 1543 in what is now Frombork, Poland. Largely unknown outside of academic circles, he died the year his major work was published, saving him from the outrage of some religious leaders who later condemned his heliocentric view of the universe as heresy.

One of those critics was Martin Luther , the infamous Vatican critic who was one of the founders of the Reformation . Luther stated that “This fool wishes to reverse the entire science of astronomy; but sacred Scripture tells us that Joshua commanded the Sun to stand still, and not the Earth.” The Vatican did eventually ban “On the Revolutions of the Heavenly Spheres” in 1616.

It was not until the early 17th century that Galileo and Johannes Kepler developed and popularized the Copernican theory, which for Galileo resulted in a trial and conviction for heresy. Following Isaac Newton ’s work in celestial mechanics in the late 17th century, acceptance of the Copernican theory spread rapidly in non-Catholic countries, and by the late 18th century the Copernican view of the solar system was almost universally accepted.

Centuries after his burial in an unmarked grave beneath the floor of the cathedral in Frombork, Copernicus’ remains were finally given a hero’s burial in 2010. His body was identified using DNA analysis of the skull, which matched the DNA found in hairs that were tucked in the pages of books that Copernicus owned.

His black granite tombstone is now marked with a heliocentric model of the solar system featuring a golden sun encircled by six of the planets.

Nicolaus Copernicus. Stanford Encyclopedia of Philosophy, Stanford University . Nicolaus Copernicus biography: Facts & discoveries. Space.com . Vatican bans Copernicus' book. Physics Today . 16th-century astronomer Copernicus reburied as hero in Poland. Associated Press .

HISTORY Vault: How the Earth Was Made

When it comes to construction, nothing compares to Mother Nature. Discover the building blocks of the planet we call home.

Sign up for Inside History

Get HISTORY’s most fascinating stories delivered to your inbox three times a week.

By submitting your information, you agree to receive emails from HISTORY and A+E Networks. You can opt out at any time. You must be 16 years or older and a resident of the United States.

More details : Privacy Notice | Terms of Use | Contact Us

Nicolaus Copernicus

Server costs fundraiser 2024.

Nicolaus Copernicus (1473-1543 CE) was a Polish astronomer who famously proposed that the Earth and other planets revolved around the Sun in a heliocentric system and not, as then widely thought, in a geocentric system where the Earth is the centre.

Copernicus’ heliocentric theory was not entirely a new idea as several earlier scholars had proposed a heliocentric system, but Copernicus additionally theorised a new order for the planets in terms of their distance from the Sun, that the Earth orbits the Sun once every year, and that the Earth turns entirely on its own axis each day. These ideas were contrary to those of the Catholic Church which considered humanity and the Earth as the proper and actual centre of God 's universe. The reaction to Copernicus' major work, De Revolutionibus Orbium Coelestium ( On the Revolutions of the Heavenly Spheres ), published in the year he died, was muted, and there was hardly a revolutionary overturning of how everyone saw the world's place in the universe, as is often claimed. Nevertheless, the astronomer's work would slowly lead to further investigations by later scientists and mathematicians who eventually proved that Copernicus' heliocentric system with a spinning Earth, although containing flaws, was essentially correct.

Nicolaus Copernicus, real name Mikołaj Kopernik, was born on 19 February 1473 CE in Toruń, Poland (then part of Prussia). His father was a successful merchant but after his death c. 1483 CE Copernicus was adopted by Lucas Watzelrode, his maternal uncle. Significantly, Watzelrode later became bishop of Warmia, and the young Nicolaus was likewise expected to pursue a career in the church. First, though, he studied astronomy at the University of Kraków and then medicine and astrology at the University of Bologna. His wide-ranging education in the liberal arts also included mathematics, philosophy , and history. His travels continued when he lectured in mathematics in Rome in 1500 CE, after which he went to the University of Padua to continue his medical studies. Finally, in 1503 CE, he received a doctorate in canon law from the University of Ferrara. This broad education would serve him well for his future investigations, but it is perhaps the astrological observations he made while in Bologna which really set his mind towards solving the problems of the heavenly bodies and their movements.

Copernicus returned to Poland in 1506 CE where he acted as his uncle's physician. His uncle also set him up as a church canon (although he never became a priest), a position which required him to collect the rents, manage the assets and oversee the finances of the bishopric of Frombork (aka Frauenburg). Despite these worldly duties, Copernicus never forgot astronomy, and he continued to pursue this field of study in his free time.

Observing the Skies

In his studies of the heavens, Copernicus had to wrestle with several problems that divided opinions amongst astronomers. There was the persistent idea, first proposed by Aristotle (384-322 BCE), that the planets moved in a uniform way through an undefined medium of invisible spheres, always at fixed distances from a central point, the Earth. This means that the universe must be made up of a series of concentric spheres. Unfortunately, this theory did not match the experience of viewing a variation in the brightness of planets in the night sky. How, then, could planets always be the same distance from the Earth?

There was another age-old and related problem in the field, this time a consequence of the theories of Claudius Ptolemy (c. 100 - c. 170 CE). Ptolemy proposed that planets moved within a small circular orbit of their own (epicycle) while still following a larger orbit (deferent) around a fixed central point, the Earth (equant) or, for Ptolemy, a point slightly away from it. The problem with this theory is that it went against the traditional and seemingly untouchable idea that planets moved uniformly and at a constant distance from the Earth in a circular orbit. If one put together Aristotle's scheme of concentric spheres and Ptolemy's scheme of orbits within orbits, then the spheres which contained the planets would wobble and at some point collide - not a possibility for an ordered universe. In the 13th century CE, Persian astronomers attempted to solve this conundrum by combining two epicycles which uniformly revolve around each other. This would create an oscillating point and explain why planets changed distance from the Earth. Copernicus knew of and studied all of these theories, but their complexity seemed contrived to explain an original model that was perhaps itself flawed. Change the central equant point and perhaps the physical behaviour of the planets would become clearer, and the theory that explained it a whole lot simpler.

The Heliocentric Solution

Copernicus worked for three decades on his theories of just how the Earth and those heavenly bodies visible in the night sky were related to each other. The telescope had not yet been invented, but by observing lunar eclipses and the movement of planets and constellations, he eventually came up with an explanation for the things he saw, perhaps by around 1514 CE. In addition, Copernicus used many observations from past astronomers, some of which were not wholly accurate.

That Copernicus was active and respected in the field of astronomy is evidenced by the invitation in 1514 CE to attend the Fifth Lateran Council. There he was to present his views on the proposed reforms to the calendar, important for Church holy days but now long out of synch with the position of the Sun on any given day. In the event, the famous astronomer never attended.

The final result of his research was nothing short of mind-blowing for the European academic community and especially the hierarchy of the Catholic Church. Copernicus proposed that the central point of the universe was not the Earth with all other bodies revolving around it. Rather, the Earth was a planet, which orbited around the Sun, the real central point of our solar system. So, too, it was not the celestial bodies like Mars , Venus , and the stars that revolved around the Earth but the Earth turning on its own axis and orbiting around the Sun, which explained their movements across the sky in a single night and over the period of a year. Further, Copernicus suggested that the Earth made a single turn on its axis in a day and took one year to orbit around the Sun. In addition, relatively small changes in the angle of the Earth's axis over time explained the precession of the equinoxes, that is, the gradual shifting of the constellations in the night sky over time, a phenomenon known since antiquity.

The reason why such visible planets as Mercury and Venus showed only a small motion in the night sky was because they orbited within the Earth's orbit of the Sun. Likewise, the often strange motions of the planets Mars, Jupiter , and Saturn could now be explained as due to their position beyond Earth's orbit where they revolved around the Sun at a slower rate. Copernicus was thus able to show that the then observable planets were in the following order from the Sun: Mercury, Venus, Earth, Mars, Jupiter, and Saturn. All of these radical ideas were presented in Copernicus' De Revolutionibus Orbium Coelestium ( On the Revolutions of the Heavenly Spheres ), a work of six volumes not actually published until 1543 CE. The delay might have been due to the author's concern for the public's reaction, but it is much more likely that he was still wrestling with details and problems of mathematics. Indeed, Copernicus himself stated that he was a mathematician writing for mathematicians, and few outside the field would have understood its contents. The change in the original title, replacing 'Spheres of the World' for 'Heavenly Spheres', does suggest the author was trying to minimise the focus on the real world and concentrate on theoretical mathematics.

The Reaction to De Revolutionibus

There were still quite a few problems to deal with, though. Copernicus' theory had done away with the prevailing explanation for the observable phenomenon of gravity, i.e. things fell to the ground because the Earth was at the centre of the universe. Another problem was that Copernicus still did not realise the planetary orbits were not perfect circles. That the orbits were elliptical was later formulated by the German astronomer Johannes Kepler (1571-1630 CE).

Even more problematic than these questions of physics, Copernicus' ideas went wholly against the traditional view of humanity's place in the universe as proposed by the Catholic Church. The idea that the Earth was the central point and the Sun and Moon orbited around it (the anthropocentric model) was in keeping with the idea that humanity was also the focus, indeed, the whole point of the universe's existence as created by God. The idea that the Earth was the centre of the known universe went back to antiquity and was difficult to shift (even if some ancient thinkers had proposed a heliocentric system).

Fortunately for Copernicus, although it happened without his permission, Andreas Osiander (1498–1552 CE), the Lutheran minister who had supervised the publication of De Revolutionibus , had inserted a preface which stated the work was intended as a theoretical aid to mathematicians and not a presentation of how the universe was in reality. This view was in keeping with the times as astronomy and mathematics were regarded as theoretical subjects. Such work as the De Revolutionibus could not seriously attempt to change the general view of the physical world as that was then considered a task for natural philosophy. The preface and traditional separation of academic subjects at the time may well have saved the work and Copernicus' memory - he had died in Frombork shortly before publication on 24 May 1543 CE - from the full wrath of the Catholic Church.

As it happened, reaction to Copernicus' theory was rather tame all round, and even the small pool of astronomy scholars who were its intended audience measured barely a ripple of reaction. However, it was a slow-burner and as later scientists began to explore the same themes and seek ever more accurate astronomical tables, so Copernicus' work came to the fore a few years after its publication. So much so, the reformist Martin Luther (1483-1546 CE) denounced the De Revolutionibus . By 1616 CE, it was more widely known and condemned as heretical by Church authorities who listed it as a forbidden book.

Despite Christianity 's attempt to brush Copernicus' theories under the ecclesiastical carpet, his work began a long process of scientifically determining the nature of our solar system and its place in the wider universe. Over the following centuries, great thinkers like Galileo (1564-1642 CE) and Isaac Newton (1642-1727 CE) would add to an ever-growing body of knowledge regarding the movement and properties of planets, moons, and stars. In this sense, Copernicus was one of the first protagonists in the scientific revolution that began in the Renaissance period. In honour of his contribution to this process and modern astronomy, one of the largest craters on the Moon is named after Copernicus.

Subscribe to topic Related Content Books Cite This Work License

Bibliography

• Blockmans, Wim & Hoppenbrouwers, Peter. Introduction to Medieval Europe 300–1500. Routledge, 2017.
• Campbell, Gordon. The Oxford Illustrated History of the Renaissance. Oxford University Press, 2019.
• Rice Jr., Eugene, F. & Anthony Grafton. The Foundations of Early Modern Europe, 1460-1559. W. W. Norton & Company, 1994.
• Rundle, David. The Hutchinson Encyclopedia of the Renaissance. Hodder Arnold, 2000.
• Westman, R.S., Nicolaus Copernicus | Facts, Accomplishments, & Theory , accessed 23 Oct 2020.
• Wyatt, Michael. The Cambridge Companion to the Italian Renaissance. Cambridge University Press, 2014.

About the Author

Translations

We want people all over the world to learn about history. Help us and translate this definition into another language!

Questions & Answers

What did nicolaus copernicus discover, what are 5 facts about nicolaus copernicus, in what way was copernicus' theory revolutionary, related content.

Hipparchus of Nicea

Renaissance Humanism

Greek Astronomy

Menelaus of Alexandria

Helen (Play)

Free for the world, supported by you.

World History Encyclopedia is a non-profit organization. For only $5 per month you can become a member and support our mission to engage people with cultural heritage and to improve history education worldwide.

Recommended Books

External Links

Cite this work.

Cartwright, M. (2020, October 26). Nicolaus Copernicus . World History Encyclopedia . Retrieved from https://www.worldhistory.org/Nicolaus_Copernicus/

Chicago Style

Cartwright, Mark. " Nicolaus Copernicus ." World History Encyclopedia . Last modified October 26, 2020. https://www.worldhistory.org/Nicolaus_Copernicus/.

Cartwright, Mark. " Nicolaus Copernicus ." World History Encyclopedia . World History Encyclopedia, 26 Oct 2020. Web. 11 Sep 2024.

License & Copyright

Submitted by Mark Cartwright , published on 26 October 2020. The copyright holder has published this content under the following license: Creative Commons Attribution-NonCommercial-ShareAlike . This license lets others remix, tweak, and build upon this content non-commercially, as long as they credit the author and license their new creations under the identical terms. When republishing on the web a hyperlink back to the original content source URL must be included. Please note that content linked from this page may have different licensing terms.

• HISTORY MAGAZINE

Copernicus's revolutionary ideas reorganized the heavens

This secretive astronomer devoted his entire life to sun-centered cosmic theories as larger questions of faith were dividing Europe nearly 500 years ago.

Rumors were circulating in the 1530s that Nicolaus Copernicus, a cathedral cleric in a small Polish city, had written a revolutionary theory on the cosmos. To the frustration of many, however, the secretive clergyman was refusing to publish it.

Curiosity came from many quarters. One letter, written in 1536, begged for more information. It praised Copernicus’s “new theory of the Universe according to which the Earth moves and the Sun occupies the basic, and hence, central, position.” Its author was Cardinal Nikolaus von Schönberg, a prince of the Catholic Church.

By placing the sun at the center, Copernicus’s idea overturned the ideas devised by the second-century astronomer Ptolemy. In Ptolemy’s theory the sun and planets orbited the Earth, which was regarded as the orthodox model across the Christian world. Through decades of work, Copernicus had slowly and carefully found a new way of organizing the heavens, but his reticence kept these new ideas isolated from the public, who could only speculate about them.

A man of both science and faith, Copernicus lived during a time of great change in Europe. A new flowering of humanist thought was spreading throughout the continent, as scholars and artists looked back to the classical era and brought its influence to bear on art, architecture, literature, politics, and science. After Martin Luther published his Ninety-Five Theses in 1517, a religious revolution began that would roil the Catholic Church and form new denominations. Throughout all this tumult, Copernicus held fast at the center, methodically crafting his own astronomical revolution.

Faith in astronomy

A century before Galileo’s persecution, the church’s attitude to- ward astronomy was more open. The Julian calendar, then in use, had become so inexact that it fell out of time with the seasons. Copernicus submitted a statement to a 1512-16 council convened to address the problem, in which he called for more accurate observations. A new “Gregorian” calendar with leap years was introduced under Pope Gregory XIII in 1582 and is still in use today.

A Renaissance man

Copernicus was born Mikolaj Kopernik in 1473, in Torun, Poland. (Following the custom among scholars in the Renaissance, he later latinized his name.) A major port on the Vistula River, Torun was part of a loose grouping of rich, northern trading cities known as the Hanseatic League. Copernicus’s father was a merchant, and historians speculate that he and his family dealt in copper, an association which gave rise to the family name. When Copernicus was 10 years old, his father died, and he went to live with his mother’s brother, Lucas Watzenrode. Later appointed the Bishop of Warmia in northern Poland, Watzenrode became an important patron to his nephew. (See also: How table manners as we know them were a Renaissance invention .)

Copernicus began his university studies in 1491 at the Academy of Krakow (today the Jagiellonian University), which was then attracting some of Europe’s finest minds in mathematics and astronomy. Cosmopolitan Krakow, full of merchants and intellectuals, was an exciting place to receive an education. Reports of startling discoveries of new lands across the Atlantic by a Genoese sailor, Christopher Columbus, and the new humanist teachings of the Renaissance, were arriving in Poland from southern Europe. Krakow was the adoptive home of the flamboyant Italian scholar Filippo Buonaccorsi, secretary to the Polish king and tutor to his children.

After several years, Copernicus was drawn to Italy, the epicenter of humanist learning at the time. Whatever diffidence he later showed in his scientific theories, Copernicus did not lack funds or time to pursue a solid student career there. In 1497 his uncle appointed him a canon at the cathedral of Frombork in his own diocese, even though Copernicus had begun his Italian studies a year before. The position gave him ample financial security. Well over a decade would pass before the absentee canon took up his duties on the chilly shores of the Baltic; in the interim, Copernicus dedicated himself to university life, first at Bologna, then at Padua, finally emerging as a doctor from the small university of Ferrara in 1503.

Higher education in this period was much more far-ranging than the specialism of a modern university. His studies included the intricacies of civil and church law, deemed essential for a high-ranking career in the clergy. In addition, Copernicus immersed himself in medicine and mathematics. This pairing was regarded as natural, epitomized in the 16th-century humanist scholar Jakob Milich, who served as both a professor of mathematics and anatomy. In his later career Copernicus would also be known as much as a physician as a mathematician.

Another discipline that intrigued Copernicus was the study of the stars, which encompassed both astronomy and astrology. Today astronomy is regarded as a science, based on observation, while astrology—the idea that heavenly bodies affect the health and fortunes of people— is not. In Copernicus’s time, however, scholars made no clear-cut distinction between the two. Bologna University’s astronomer, for example, Domenico Maria de Novara, was tasked with providing astrological predictions for the city’s rulers and nobility.

Novara proved to be an important influence on the young Polish stargazer. For a while, Copernicus lodged with him, and the two scholars made observations together. The invention of the telescope would not take place for over a century, so the two men relied on naked-eye observation, using their knowledge of Greek to consult treatises translated from Arabic, or the ancient classical works, such as the writings of Ptolemy. Some of Ptolemy’s assertions were already being questioned by Novara. He introduced Copernicus to the work of Johann Müller, known by his humanistic sobriquet Regiomontanus, another skeptic of the Ptolemaic model.

On March 9, 1497, together with Novara, Copernicus made his first known astronomical observation: At 11 p.m. both watched as the moon briefly eclipsed a distant star, Aldebaran, an event that cast doubt on Ptolemy’s theory of the distance of the moon from the Earth. The idea that the Sun was fixed in the center of the cosmos was starting to take hold in Copernicus’s mind.

A theory evolves

In 1503 Copernicus returned north to his uncle’s diocese in Poland. He spent several years working alongside his uncle as both his secretary and personal physician. He took part in minor acts of diplomacy on trips around Poland and also published a translation into Latin of a work by a seventh-century Byzantine historian. After his uncle’s death in 1512, he devoted more time to the duties of a church canon, which were largely administrative: collecting rents, managing finances, securing military resources, and overseeing the local businesses (bakeries, breweries, and mills) of the diocese.

During this time Copernicus also continued his astronomical work. He earned a solid reputation as a leading mind of the time. In 1514 Copernicus was invited to contribute to a council to reform the calendar, so as to enable the church to fix feast days with more accuracy. Later, as an administrator at the Bishop’s Castle in the Warmian city of Olsztyn, he produced an astronomical table, or heliograph, still visible on one of the walls of the castle cloister, for observing the movements of the sun.

Sometime before 1514, Copernicus wrote a small treatise, the Commentariolus (“little commentary” in Latin). He circulated a few hand- written copies among a learned elite. This small work, described by scholars as “a manuscript of six leaves,” first presented Copernicus’s notion that the Earth and other planets move while the sun stands still. Using his observations and other research, Copernicus calculated the time each planet took to go around the sun: Mercury (88 days), Venus (225 days), Earth (one year), Mars (1.9 years), Jupiter (12 years), and Saturn (30 years). This pamphlet was the first milestone in Copernicus’s journey to redefine the universe.

Clear Skies

A tradition holds that Copernicus made astronomical observations from a tower in the cathedral complex at Frombork. He found his adoptive home far from ideal for this purpose, and in De revolutionibus expresses his conservative view that things were better in classical times, especially in the land of Ptolemy: “The ancients had the advantage of a clearer sky; the Nile does not exhale such misty vapors as those we get from the Vistula.”

Gaining ground

The Commentariolus’ s early findings raised questions and exposed problems with the data. To avoid errors in his calculations and assumptions, Copernicus spent decades of his life finding the strongest evidence to support his epoch- shaking idea. The Commentariolus was only circulated among a few scholars and caused very little commotion.

In the meantime, Copernicus was busy with his duties with the church, whose very foundations were shaken by Martin Luther’s dramatic challenge to papal authority in 1517. Throughout the 1520s he helped steer his diocese through the ensuing conflict, taking part in diplomatic missions and even proposing reforms to the monetary system.

Many years later, the Commentariolus came to the attention of German humanist Johann Albrecht Widmannstetter. In 1533 he gave a lecture in the Vatican gardens before Pope Clement VII and explained Copernicus’s still unpublished theory. The church’s interest in his work was genuine, and at this time did not see a sun- centered universe as threatening to orthodoxy.

A young Austrian mathematics professor, Georg Joachim Rheticus, was instrumental in helping Copernicus push heliocentrism out to the wider world. In 1539 Rheticus moved to Frombork to work alongside the astronomer for two years and became Copernicus’s devoted disciple.

After much per- suasion, Rheticus finally managed to convince Copernicus to let him publish an account of his theory in 1540. The treatise, called The First Account of the Book on the Revolutions by Nicolaus Copernicus, piqued the interest of astronomers all over Europe. They would not have to wait long for a full accounting of Copernicus’s astronomical work.

Mapping the stars

Two years later, the manuscript of De revolutionibus orbium coelestium libri VI (Six Books Concerning the Revolutions of the Heavenly Orbs), was taken to Nuremberg to be printed by a leading scientific publisher. The lavishly illustrated work included 142 woodcuts. There is evidence that Copernicus made numerous corrections and edits to the first part of the work.

You May Also Like

These musician siblings became rock stars—in astronomy

We’re in Mercury retrograde. Here’s what that really means.

NASA just found a question mark in space. What exactly is it?

A popular story (perhaps apocryphal) is that a first edition of the book was brought to his deathbed as he lay dying from a stroke in 1543. Copernicus drew his last breath on May 24, having completed his work. Now the rest of the world would see how this humble cleric would reorganize the heavens.

Economist and astronomer

As Copernicus wrestled with his scientific ideas, his duties as a church administrator led him to develop an important theory of economics. In the 1520s, war between the Teutonic knightly order and Poland affected Frombork and Warmia. Political instability had led to gold and silver being reduced in the coinage, which in turn led to dramatic inflation. In 1528 Copernicus published an influential treatise warning on how debasing coins would lead to the disappearance of high-value, “good” coins from circulation, with baleful economic effects. The phenomenon was also described by the English banker Thomas Gresham, and the Gresham-Copernicus law (as it is now known) is often summarized as “Bad money drives out good.”

Moving heaven and earth

De revolutionibus expands the fundamental ideas put forth in Commentariolus. It declares that the Earth orbits the sun in the course of a year, turns around its own axis in the course of a day, and annually tilts on its axis. His sequencing of the planets from the sun—placing the Earth third in line—was to become the accepted order. In his introduction, addressed to Pope Paul III, he explains why he took so long to publish his work:

[T]he scorn which I had reason to fear on account of the novelty and unconventionality of my opinion almost induced me to abandon completely the work which I had undertaken.

His friends were able to convince him otherwise:

As crazy as my doctrine of the earth’s motion now appeared to most people, the argument ran, so much the more admiration and thanks would it gain after they saw the publication of my writings dispel the fog of absurdity by most luminous proofs.

In other ways, however, Copernicus did not break new ground. Solar centrality was not a new idea, as he acknowledged: “I first found in Cicero that Hicetas [a Greek philosopher from the fourth century B.C.] supposed the earth to move.”

Copernicus also got some things wrong. He held on to the idea that orbits were perfectly circular, which was later disproved by Johannes Kepler, who demonstrated that orbits are elliptical. In order to reconcile circular orbits with actual planetary behavior, Copernicus continued the tradition, developed by Ptolemy, of arguing that planets spin on wheels, known as epicycles.

Upon its publication, the Catholic Church was not hostile to De revolutionibus. Copernicus had made no attempt to challenge papal authority in his writings, and his dedication goes to great lengths to establish his respect for the pope. By the 1560s several universities, including the University of Salamanca in Spain, a deeply orthodox Catholic institution, had De revolutionibus on the curriculum.

This tolerant attitude would shift by the early 1600s, when Galileo Galilei was using the newly invented telescope to scan the skies. Even as he was becoming increasingly convinced that Copernicus was correct, Galileo was warned by the church in 1616 not to “hold or defend” the Copernican theory. The same year, Copernicus’s De revolutionibus was placed on the church’s Index of Forbidden Books.

Wheels Within Wheels

Copernicus could not let go of an idea enshrined in 350 B.C. by Aristotle in On the Heavens: “The circle is a perfect thing.” Only by mounting certain planets on turning wheels known as epicycles could 15th-century astronomers make circular orbits fit with actual planetary behavior. Drawn in 1756 by Scottish astronomer James Ferguson, a diagram of the patterns produced by epicycles reveals how complex their motions would be.

Science continued moving forward even as Galileo was being silenced. Kepler was working on his laws of planetary motion, and in time, the Copernican model would become universally accepted. Some historians even date the beginnings of the scientific revolution to 1543 and the publication of De revolutionibus . As the 21st- century American science writer Dava Sobel put it: “Thanks to Copernicus, the Sun doesn’t set. The Earth turns.”

Related Topics

• ASTRONOMERS
• CATHOLICISM

See the summer solstice from a Roman emperor’s party cave

How reading the night sky helped Black Americans survive

How notes from the mothers of astronomy were reclaimed in art

How far away is the sun? They went on a perilous journey to find out.

How people viewed the Moon before Apollo and Artemis

• Environment
• Paid Content

History & Culture

• History & Culture
• Mind, Body, Wonder
• Adventures Everywhere
• Terms of Use
• Privacy Policy
• Your US State Privacy Rights
• Children's Online Privacy Policy
• Interest-Based Ads
• About Nielsen Measurement
• Do Not Sell or Share My Personal Information
• Nat Geo Home
• Attend a Live Event
• Book a Trip
• Inspire Your Kids
• Shop Nat Geo
• Visit the D.C. Museum
• Learn About Our Impact
• Support Our Mission
• Advertise With Us
• Customer Service
• Renew Subscription
• Manage Your Subscription
• Work at Nat Geo
• Sign Up for Our Newsletters
• Contribute to Protect the Planet

Copyright © 1996-2015 National Geographic Society Copyright © 2015-2024 National Geographic Partners, LLC. All rights reserved

Nicolaus Copernicus

Astronomer Nicolaus Copernicus was instrumental in establishing the concept of a heliocentric solar system, in which the sun, rather than the earth, is the center of the solar system.

(1473-1543)

Who Was Copernicus?

Circa 1508, Nicolaus Copernicus developed his own celestial model of a heliocentric planetary system. Around 1514, he shared his findings in the Commentariolus . His second book on the topic, De revolutionibus orbium coelestium , was banned by the Roman Catholic Church decades after his May 24, 1543 death in Frombork.

Early Life and Education

Famed astronomer Nicolaus Copernicus (Mikolaj Kopernik, in Polish) came into the world on February 19, 1473. The fourth and youngest child born to Nicolaus Copernicus Sr. and Barbara Watzenrode, an affluent copper merchant family in Torun, West Prussia, Copernicus was technically of German heritage. By the time he was born, Torun had ceded to Poland, rendering him a citizen under the Polish crown. German was Copernicus' first language, but some scholars believe that he spoke some Polish as well.

During the mid-1480s, Copernicus' father passed away. His maternal uncle, Bishop of Varmia Lucas Watzenrode, generously assumed a paternal role, taking it upon himself to ensure that Copernicus received the best possible education. In 1491, Copernicus entered the University of Cracow, where he studied painting and mathematics. He also developed a growing interest in the cosmos and started collecting books on the topic.

Established as Canon

By mid-decade, Copernicus received a Frombork canon cathedral appointment, holding onto the job for the rest of his life. It was a fortunate stroke: The canon's position afforded him the opportunity to fund the continuation of his studies for as long as he liked. Still, the job demanded much of his schedule; he was only able to pursue his academic interests intermittently, during his free time.

In 1496, Copernicus took leave and traveled to Italy, where he enrolled in a religious law program at the University of Bologna. There, he met astronomer Domenico Maria Novara — a fateful encounter, as the two began exchanging astronomical ideas and observations, ultimately becoming housemates. Historian Edward Rosen described the relationship as follows: "In establishing close contact with Novara, Copernicus met, perhaps for the first time in his life, a mind that dared to challenge the authority of [astrologist Claudius Ptolemy] the most eminent ancient writer in his chosen fields of study."

In 1501, Copernicus went on to study practical medicine at the University of Padua. He did not, however, stay long enough to earn a degree, since the two-year leave of absence from his canon position was nearing expiration. In 1503, Copernicus attended the University of Ferrara, where he took the necessary exams to earn his doctorate in canon law. He hurried back home to Poland, where he resumed his position as canon and rejoined his uncle at an Episcopal palace. Copernicus remained at the Lidzbark-Warminski residence for the next several years, working and tending to his elderly, ailing uncle and exploring astronomy.

In 1510, Copernicus moved to a residence in the Frombork cathedral chapter. He would live there as a canon for the duration of his life.

Copernicus' Theory: Heliocentric Solar System

Throughout the time he spent in Lidzbark-Warminski, Copernicus continued to study astronomy. Among the sources that he consulted was Regiomontanus's 15th-century work Epitome of the Almagest , which presented an alternative to Ptolemy's model of the universe and significantly influenced Copernicus' research.

Scholars believe that by around 1508, Copernicus had begun developing his own celestial model, a heliocentric planetary system. During the second century A.D., Ptolemy had invented a geometric planetary model with eccentric circular motions and epicycles, significantly deviating from Aristotle 's idea that celestial bodies moved in a fixed circular motion around the earth. In an attempt to reconcile such inconsistencies, Copernicus' heliocentric solar system named the sun, rather than the earth, as the center of the solar system. Subsequently, Copernicus believed that the size and speed of each planet's orbit depended on its distance from the sun.

Though his theory was viewed as revolutionary and met with controversy, Copernicus was not the first astronomer to propose a heliocentric system. Centuries prior, in the third century B.C., the ancient Greek astronomer Aristarchus of Samos had identified the sun as a central unit orbited by a revolving earth. But a heliocentric theory was dismissed in Copernicus' era because Ptolemy's ideas were far more accepted by the influential Roman Catholic Church, which adamantly supported the earth-based solar system theory. Still, Copernicus' heliocentric system proved to be more detailed and accurate than Aristarchus', including a more efficient formula for calculating planetary positions.

In 1513, Copernicus' dedication prompted him to build his own modest observatory. Nonetheless, his observations did, at times, lead him to form inaccurate conclusions, including his assumption that planetary orbits occurred in perfect circles. As German astronomer Johannes Kepler would later prove, planetary orbits are actually elliptical in shape.

Contributions

Around 1514, Copernicus completed a written work, Commentariolus (Latin for "Small Commentary"), a 40-page manuscript which summarized his heliocentric planetary system and alluded to forthcoming mathematical formulas meant to serve as proof.

The sketch set forth seven axioms, each describing an aspect of the heliocentric solar system: 1) Planets don't revolve around one fixed point; 2) The earth is not at the center of the universe; 3) The sun is at the center of the universe, and all celestial bodies rotate around it; 4) The distance between the Earth and Sun is only a tiny fraction of stars' distance from the Earth and Sun; 5) Stars do not move, and if they appear to, it is only because the Earth itself is moving; 6) Earth moves in a sphere around the Sun, causing the Sun's perceived yearly movement; and 7) Earth's own movement causes other planets to appear to move in an opposite direction.

Commentariolus also went on to describe in detail Copernicus' assertion that a mere 34 circles could sufficiently illustrate planetary motion. Copernicus sent his unpublished manuscript to several scholarly friends and contemporaries, and while the manuscript received little to no response among his colleagues, a buzz began to build around Copernicus and his unconventional theories.

Courting Controversy with the Catholic Church

Copernicus raised a fair share of controversy with Commentariolus and De revolutionibus orbium coelestium ("On the Revolutions of the Heavenly Spheres"), with the second work published right before his death. His critics claimed that he failed to solve the mystery of the parallax — the seeming displacement in the position of a celestial body, when viewed along varying lines of sight — and that his work lacked a sufficient explanation for why the Earth orbits the Sun.

Copernicus' theories also incensed the Roman Catholic Church and were considered heretical. When De revolutionibus orbium coelestium was published in 1543, religious leader Martin Luther voiced his opposition to the heliocentric solar system model. His underling, Lutheran minister Andreas Osiander, quickly followed suit, saying of Copernicus, "This fool wants to turn the whole art of astronomy upside down."

Osiander even went so far as to write a disclaimer stating that the heliocentric system was an abstract hypothesis that need not be seen as truth. He added his text to the book's preface, leading readers to assume that Copernicus himself had written it. By this time, Copernicus was ailing and unfit for the task of defending his work.

Ironically, Copernicus had dedicated De revolutionibus orbium coelestium to Pope Paul III. If his tribute to the religious leader was an attempt to cull the Catholic Church's softer reception, it was to no avail. The church ultimately banned De revolutionibus in 1616, though the book was eventually removed from the list of forbidden reading material.

In May 1543, mathematician and scholar Georg Joachim Rheticus presented Copernicus with a copy of a newly published De revolutionibus orbium coelestium . Suffering the aftermath of a recent stroke, Copernicus was said to have been clutching the book when he died in his bed on May 24, 1543, in Frombork, Poland.

Kepler later revealed to the public that the preface for De revolutionibus orbium coelestium had indeed been written by Osiander, not Copernicus. As Kepler worked on expanding upon and correcting the errors of Copernicus' heliocentric theory, Copernicus became a symbol of the brave scientist standing alone, defending his theories against the common beliefs of his time.

Isaac Newton

QUICK FACTS

• Name: Nicolaus Copernicus
• Birth Year: 1473
• Birth date: February 19, 1473
• Birth City: Torun
• Birth Country: Poland
• Gender: Male
• Best Known For: Astronomer Nicolaus Copernicus was instrumental in establishing the concept of a heliocentric solar system, in which the sun, rather than the earth, is the center of the solar system.
• Science and Medicine
• Education and Academia
• Astrological Sign: Pisces
• University of Bologna
• University of Cracow
• University of Ferrara
• University of Padua
• Death Year: 1543
• Death date: May 24, 1543
• Death City: Frombork
• Death Country: Poland

We strive for accuracy and fairness.If you see something that doesn't look right, contact us !

CITATION INFORMATION

• Article Title: Nicolaus Copernicus Biography
• Author: Biography.com Editors
• Website Name: The Biography.com website
• Url: https://www.biography.com/scientists/nicolaus-copernicus
• Access Date:
• Publisher: A&E; Television Networks
• Last Updated: September 14, 2022
• Original Published Date: April 3, 2014
• I am not so enamored of my own opinions that I disregard what others may think of them.
• [T]he motion of the earth can unquestionably produce the impression that the entire universe is rotating.
• For, the sun is not inappropriately called by some people the lantern of the universe, its mind by others, and its ruler by still others.
• Thus indeed, as though seated on a royal throne, the sun governs the family of planets revolving around it.
• But if one believed that the earth revolved, he would certainly be of the opinion that this movement was natural and not arbitrary.
• For my part I believe that gravity is nothing but a certain natural desire, which the divine providence of the Creator of all things has implanted in parts, to gather as a unity and a whole by combining in the form of a globe.
• So far as hypotheses are concerned, let no one expect anything certain from astronomy, which cannot furnish it, lest he accept as the truth ideas conceived for another purpose, and depart from this study a greater fool than when he entered it.
• [T]he astronomer will take as his first choice that hypothesis which is the easiest to grasp. The philosopher will perhaps rather seek the semblance of the truth. But neither of them will understand or state anything certain, unless it has been divinely revealed to him.
• Of all things visible, the highest is the heaven of the fixed stars.
• Even though what I am now saying may be obscure, it will nevertheless become clearer in the proper place.
• To know that we know what we know, and to know that we do not know what we do not know, that is true knowledge.
• For a traveler going from any place toward the north, that pole of the daily rotation gradually climbs higher, while the opposite pole drops down an equal amount.
• At rest, however, in the middle of everything is the sun.

Famous Scientists

Did This Newly Found Compass Belong to Copernicus?

Stephen Hawking

Chien-Shiung Wu

The Solar Eclipse That Made Albert Einstein a Star

Jane Goodall

Marie Curie

Howard Carter, King Tut's Tomb, and a Deadly Curse

Benjamin Banneker

Neil deGrasse Tyson

Daniel Hale Williams

Patricia Bath

Mae Jemison

• Subject List
• Take a Tour
• For Authors
• Subscriber Services
• Publications
• African American Studies
• African Studies
• American Literature
• Anthropology
• Architecture Planning and Preservation
• Art History
• Atlantic History
• Biblical Studies
• British and Irish Literature
• Childhood Studies
• Chinese Studies
• Cinema and Media Studies
• Communication
• Criminology
• Environmental Science
• Evolutionary Biology
• International Law
• International Relations
• Islamic Studies
• Jewish Studies
• Latin American Studies
• Latino Studies
• Linguistics
• Literary and Critical Theory
• Medieval Studies
• Military History
• Political Science
• Public Health

Renaissance and Reformation

• Social Work
• Urban Studies
• Victorian Literature
• Browse All Subjects

How to Subscribe

• Free Trials

In This Article Expand or collapse the "in this article" section Nicolaus Copernicus

Introduction.

• Collections of Essays
• Bibliographies
• Biographies
• Primary Sources
• Education, Career, and Death
• Origin of the Heliocentric Theory
• Renaissance Humanist Influences
• Philosophical Repercussions
• Scriptural and Religious Objections
• Celebrations

Related Articles Expand or collapse the "related articles" section about

About related articles close popup.

Lorem Ipsum Sit Dolor Amet

Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Aliquam ligula odio, euismod ut aliquam et, vestibulum nec risus. Nulla viverra, arcu et iaculis consequat, justo diam ornare tellus, semper ultrices tellus nunc eu tellus.

• Astrology, Alchemy, Magic
• Galileo Galilei
• Giordano Bruno
• Italian Visitors
• Johannes Kepler
• Nicholas of Cusa
• Polish Literature: Renaissance
• Scientific Revolution

Other Subject Areas

Forthcoming articles expand or collapse the "forthcoming articles" section.

• Giulia Gonzaga
• Margaret Cavendish
• Merchant Adventurers
• Find more forthcoming articles...
• Export Citations
• Share This Facebook LinkedIn Twitter

Nicolaus Copernicus by André Goddu LAST REVIEWED: 24 May 2018 LAST MODIFIED: 24 May 2018 DOI: 10.1093/obo/9780195399301-0252

Nicolaus Copernicus (b. 1473–d. 1543) was the first modern author to propose a heliocentric theory of the universe. From the time that Ptolemy of Alexandria ( c . 150  CE ) constructed a mathematically competent version of geocentric astronomy to Copernicus’s mature heliocentric version (1543), experts knew that the Ptolemaic system diverged from the geocentric concentric-sphere conception of Aristotle. Copernicus cited disagreements among his predecessors over observations, principles, assumptions, explanations, and, even worse, over the order of the planets, the structure of the universe, and the commensurability of its parts. Relying on Renaissance humanist predecessors and contemporaries, Copernicus expressed deep dissatisfaction with the confusion in astronomy, and he intimated that the artisan who created the universe for our sake also created humans with the capacity to discover and understand the structure of that universe with certainty. Copernicus did not explain, however, exactly how he came to the conclusions that the problem lay in geocentrism and the solution in heliocentrism. As a result, experts have been trying to reconstruct his path to the heliocentric theory ever since. The Copernican revolution in cosmography (later called “cosmology”) had a profound impact on natural philosophy (motions of bodies, the elements, finiteness of the universe), logic, the liberal arts, and the structure of the cosmos. The Copernican theory also challenged standard interpretations of the Bible and conceptions reinforced by traditional religion about the place of humankind in the universe and its ultimate end.

After Ptolemy, most astronomers and philosophers followed a compromise interpretation of geocentricism that imbedded the Ptolemaic eccentric and epicycle models in concentric spheres ( Pedersen 1974 , Grant 1994 , Ptolemy 1998 ). Some mathematicians and natural philosophers, however, objected to some of Ptolemy’s models and solutions, and they proposed alternative geometrical solutions ( Kennedy and Roberts 1959 , Hartner 1975 , Ragep 2007 , Feldhay and Ragep 2017 ), or demanded genuine concentric solutions to explain the motions of the celestial bodies ( Bono 1995 ). The details of previous critiques and summaries served Copernicus in his own reformation of ancient astronomy ( Swerdlow and Neugebauer 1984 ).

Bono, Mario di. “Copernicus, Amico, Fracastoro and Tusi’s Device: Observations on the Use and Transmission of a Model.” Journal for the History of Astronomy 26 (1995): 133–154.

DOI: 10.1177/002182869502600203

Explains the concentric alternatives to Ptolemy and challenges the standard orthodoxy about Copernicus’s reliance on Arabic predecessors.

Feldhay, Rivka, and F. Jamil Ragep, eds. Before Copernicus: The Cultures and Contexts of Scientific Learning in the Fifteenth Century . Montreal: McGill-Queen’s University Press, 2017.

Most recent collection of essays dealing with the background to Copernicus’s achievement. The quality of essays is uneven, but two dealing most directly with Copernicus, by Edith Sylla and Michael Shank, are excellent.

Grant, Edward. Planets, Stars, and Orbs . Cambridge, UK: Cambridge University Press, 1994.

A synthesis of Grant’s research in which he describes the compromise systems of the Middle Ages, especially the three-orb system that incorporated eccentrics and epicycles inside concentric spheres.

Hartner, Willy. “The Islamic Astronomical Background to Nicholas Copernicus.” In Colloquia Copernicana 3: Proceedings of a Joint Symposium of the IAU and the IUHPS, Toruń, Poland, 1973 . Edited by Marian Biskup, Jerzy Bukowski, and Paweł Czartoryski, 7–16. Wrocław, Poland: Zakład Narodowy im. Ossolińskich, 1975.

One of the first to notice similarities between Islamic mathematical models and Copernicus’s models, and suggested Copernicus’s dependence on Islamic predecessors.

Kennedy, E. S., and Victor Roberts. “The Planetary Theory of Ibn al-Shatir.” Isis 50 (1959): 227–235.

DOI: 10.1086/348774

Discovered similarities between earlier Islamic models and those of Copernicus. Available online for purchase or by subscription.

Pedersen, Olaf. A Survey of the Almagest . Odense, Denmark: Odense University Press, 1974.

The author provides the most authoritative guide in English to Ptolemy’s Almagest .

Ptolemy, Claudius. Ptolemy’s Almagest. Translated by Gerald Toomer. Princeton, NJ: Princeton University Press, 1998.

The standard and authoritative translation and commentary in English.

Ragep, F. Jamil. “Copernicus and His Islamic Predecessors.” History of Science 45 (2007): 65–81.

DOI: 10.1177/007327530704500103

The most thorough and technical in arguing for Copernicus’s reliance on Islamic predecessors.

Swerdlow, Noel, and Otto Neugebauer. Mathematical Astronomy in Copernicus’s De Revolutionibus. New York: Springer, 1984.

DOI: 10.1007/978-1-4613-8262-1

The authoritative mathematical analysis of Copernicus’s major work; in two parts.

back to top

Users without a subscription are not able to see the full content on this page. Please subscribe or login .

Oxford Bibliographies Online is available by subscription and perpetual access to institutions. For more information or to contact an Oxford Sales Representative click here .

• About Renaissance and Reformation »
• Meet the Editorial Board »
• Aemilia Lanyer
• Agrippa d’Aubigné
• Alberti, Leon Battista
• Alexander VI, Pope
• Andrea del Verrocchio
• Andrea Mantegna
• Andreas Bodenstein von Karlstadt
• Anne Boleyn
• Anne Bradstreet
• Aretino, Pietro
• Ariosto, Ludovico
• Art and Science
• Art, German
• Art in Renaissance England
• Art in Renaissance Florence
• Art in Renaissance Siena
• Art in Renaissance Venice
• Art Literature and Theory of Art
• Art of Poetry
• Art, Spanish
• Art, 16th- and 17th-Century Flemish
• Art, 17th-Century Dutch
• Artemisia Gentileschi
• Ascham, Roger
• Askew, Anne
• Astell, Mary
• Augustinianism in Renaissance Thought
• Autobiography and Life Writing
• Avignon Papacy
• Bacon, Francis
• Banking and Money
• Barbaro, Ermolao, the Younger
• Barbaro, Francesco
• Baron, Hans
• Baroque Art and Architecture in Italy
• Barzizza, Gasparino
• Bathsua Makin
• Beaufort, Margaret
• Bellarmine, Cardinal
• Bembo, Pietro
• Benito Arias Montano
• Bernardino of Siena, San
• Beroaldo, Filippo, the Elder
• Bessarion, Cardinal
• Biondo, Flavio
• Bishops, 1550–1700
• Bishops, 1400-1550
• Black Death and Plague: The Disease and Medical Thought
• Boccaccio, Giovanni
• Bohemia and Bohemian Crown Lands
• Borgia, Cesare
• Borgia, Lucrezia
• Borromeo, Cardinal Carlo
• Bosch, Hieronymous
• Bracciolini, Poggio
• Brahe, Tycho
• Bruegel, Pieter the Elder
• Bruni, Leonardo
• Bruno, Giordano
• Bucer, Martin
• Budé, Guillaume
• Buonarroti, Michelangelo
• Burgundy and the Netherlands
• Calvin, John
• Camões, Luís de
• Cardano, Girolamo
• Cardinal Richelieu
• Carvajal y Mendoza, Luisa De
• Cary, Elizabeth
• Casas, Bartolome de las
• Castiglione, Baldassarre
• Catherine of Siena
• Catholic/Counter-Reformation
• Catholicism, Early Modern
• Cecilia del Nacimiento
• Cellini, Benvenuto
• Cervantes, Miguel de
• Charles V, Emperor
• China and Europe, 1550-1800
• Christian-Muslim Exchange
• Christine de Pizan
• Church Fathers in Renaissance and Reformation Thought, The
• Ciceronianism
• Cities and Urban Patriciates
• Civic Humanism
• Civic Ritual
• Classical Tradition, The
• Clifford, Anne
• Colet, John
• Colonna, Vittoria
• Columbus, Christopher
• Comenius, Jan Amos
• Commedia dell'arte
• Concepts of the Renaissance, c. 1780–c. 1920
• Confraternities
• Constantinople, Fall of
• Contarini, Gasparo, Cardinal
• Convent Culture
• Conversos and Crypto-Judaism
• Copernicus, Nicolaus
• Cornaro, Caterina
• Cosimo I de’ Medici
• Cosimo il Vecchio de' Medici
• Council of Trent
• Crime and Punishment
• Cromwell, Oliver
• Cruz, Juana de la, Mother
• Cruz, Juana Inés de la, Sor
• d'Aragona, Tullia
• Datini, Margherita
• Davies, Eleanor
• de Commynes, Philippe
• de Sales, Saint Francis
• de Valdés, Juan
• Death and Dying
• Decembrio, Pier Candido
• Dentière, Marie
• Des Roches, Madeleine and Catherine
• d’Este, Isabella
• di Toledo, Eleonora
• Dolce, Ludovico
• Donne, John
• Drama, English Renaissance
• Dürer, Albrecht
• du Bellay, Joachim
• Du Guillet, Pernette
• Dutch Overseas Empire
• Early Modern Period, Racialization in the
• Ebreo, Leone
• Edmund Campion
• Edward IV, King of England
• Elizabeth I, the Great, Queen of England
• Emperor, Maximilian I
• England, 1485-1642
• English Overseas Empire
• English Puritans, Quakers, Dissenters, and Recusants
• Environment and the Natural World
• Epic and Romance
• Europe and the Globe, 1350–1700
• European Tapestries
• Family and Childhood
• Fedele, Cassandra
• Federico Barocci
• Female Lay Piety
• Ferrara and the Este
• Ficino, Marsilio
• Filelfo, Francesco
• Fonte, Moderata
• Foscari, Francesco
• France in the 17th Century
• France in the 16th Century
• Francis Xavier, St
• Francisco Jiménez de Cisneros
• French Law and Justice
• French Renaissance Drama
• Fugger Family
• Galilei, Galileo
• Gallicanism
• Gambara, Veronica
• Garin, Eugenio
• General Church Councils, Pre-Trent
• Geneva (1400-1600)
• Genoa 1450–1700
• George Buchanan
• George of Trebizond
• Georges de La Tour
• Giambologna
• Ginés de Sepúlveda, Juan
• Giustiniani, Bernardo
• Góngora, Luis de
• Gournay, Marie de
• Greek Visitors
• Guarino da Verona
• Guicciardini, Francesco
• Guilds and Manufacturing
• Hamburg, 1350–1815
• Hanseatic League
• Henry VIII, King of England
• Herbert, George
• Hispanic Mysticism
• Historiography
• Hobbes, Thomas
• Holy Roman Empire 1300–1650
• Homes, Foundling
• Humanism, The Origins of
• Hundred Years War, The
• Hungary, The Kingdom of
• Hutchinson, Lucy
• Iconology and Iconography
• Ignatius of Loyola, Saint
• Inquisition, Roman
• Isaac Casaubon
• Isabel I, Queen of Castile
• Italian Wars, 1494–1559
• Ivan IV the Terrible, Tsar of Russia
• Jacques Lefèvre d’Étaples
• Japan and Europe: the Christian Century, 1549-1650
• Jeanne d’Albret, queen of Navarre
• Jewish Women in Renaissance and Reformation Europe
• Jews and Christians in Venice
• Jews and the Reformation
• Jews in Amsterdam
• Jews in Florence
• Joan of Arc
• Jonson, Ben
• Joseph Justus Scaliger
• Juan de Torquemada
• Juana the Mad/Juana, Queen of Castile
• Kepler, Johannes
• King of France, Francis I
• King of France, Henri IV
• Kristeller, Paul Oskar
• Labé, Louise
• Landino, Cristoforo
• Last Wills and Testaments
• Laura Cereta
• Leibniz, Gottfried Wilhelm
• Leonardo da Vinci
• Leoni, Leone and Pompeo
• Leto, Giulio Pomponio
• Letter Writing and Epistolary Culture
• Literary Criticism
• Literature, French
• Literature, Italian
• Literature, Late Medieval German
• Literature, Penitential
• Literature, Spanish
• Locke, John
• Lorenzo de' Medici
• Lorenzo Ghiberti
• Louis XI, King of France
• Louis XIII, King of France
• Louis XIV, King of France
• Lucas Cranach the Elder
• Lucretius in Renaissance Thought
• Luther, Martin
• Lyric Poetry
• Machiavelli, Niccolo
• Macinghi Strozzi, Alessandra
• Malatesta, Sigismondo
• Manetti, Giannozzo
• Mantovano (Battista Spagnoli), Battista
• Manuel Chrysoloras
• Manuzio, Aldo
• Margaret Clitherow
• Margaret Fell Fox
• Margery Kempe
• Marinella, Lucrezia
• Marino Sanudo
• Marlowe, Christopher
• Marriage and Dowry
• Mary Stuart (Mary, Queen of Scots)
• Mary Tudor, Queen of England
• Masculinity
• Medici Bank
• Medici, Catherine de'
• Medici Family, The
• Mediterranean
• Memling, Hans
• Merici, Angela
• Milan, 1535–1706
• Milan to 1535
• Milton, John
• Mirandola, Giovanni Pico della
• Monarchy in Renaissance and Reformation Europe, Female
• Montaigne, Michel de
• More, Thomas
• Morone, Cardinal Giovanni
• Naples, 1300–1700
• Navarre, Marguerite de
• Netherlandish Art, Early
• Netherlands (Dutch Revolt/ Dutch Republic), The
• Netherlands, Spanish, 1598-1700, the
• Nettesheim, Agrippa von
• Newton, Isaac
• Niccoli, Niccolò
• Nicolas Malebranche
• Ottoman Empire
• Ovid in Renaissance Thought
• Panofsky, Erwin
• Paolo Veronese
• Parr, Katherine
• Patronage of the Arts
• Perotti, Niccolò
• Persecution and Martyrdom
• Peter the Great, Tsar of Russia
• Petrus Ramus and Ramism
• Philip Melanchthon
• Philips, Katherine
• Piccolomini, Aeneas Sylvius
• Piero della Francesca
• Pierre Bayle
• Pilgrimage in Early Modern Catholicism
• Plague and its Consequences
• Platonism, Neoplatonism, and the Hermetic Tradition
• Poetry, English
• Pole, Cardinal Reginald
• Polish Literature: Baroque
• Polish-Lithuanian Commonwealth, The
• Political Thought
• Poliziano, Angelo
• Polydore Vergil
• Pontano, Giovanni Giovano
• Pope Innocent VIII
• Pope Nicholas V
• Pope Paul II
• Portraiture
• Poulain de la Barre, Francois
• Poverty and Poor Relief
• Prince Henry the Navigator
• Printing and the Book
• Printmaking
• Pulter, Hester
• Purity of Blood
• Quirini, Lauro
• Rabelais, François
• Reformation and Hussite Revolution, Czech
• Reformation and Wars of Religion in France, The
• Reformation, English
• Reformation, German
• Reformation, Italian, The
• Reformation, The
• Reformations and Revolt in the Netherlands, 1500–1621
• Renaissance, The
• Reuchlin, Johann
• Revolutionary England, 1642-1702
• Ricci, Matteo
• Richard III
• Rienzo, Cola Di
• Roman and Iberian Inquisitions, Censorship and the Index i...
• Ronsard, Pierre de
• Roper, Margeret More
• Royal Regencies in Renaissance and Reformation Europe, 140...
• Rubens, Peter Paul
• Russell, Elizabeth Cooke Hoby
• Russia and Muscovy
• Ruzante Angelo Beolco
• Saint John of the Cross
• Saints and Mystics: After Trent
• Saints and Mystics: Before Trent
• Salutati, Coluccio
• Sandro Botticelli
• Sarpi, Fra Paolo
• Savonarola, Girolamo
• Scandinavia
• Scholasticism and Aristotelianism: Fourteenth to Seventeen...
• Schooling and Literacy
• Scève, Maurice
• Sephardic Diaspora
• Sforza, Caterina
• Sforza, Francesco
• Shakespeare, William
• Ships/Shipbuilding
• Sidney Herbert, Mary, Countess of Pembroke
• Sidney, Philip
• Simon of Trent
• Sir Robert Cecil
• Sixtus IV, Pope
• Skepticism in Renaissance Thought
• Slavery and the Slave Trade, 1350–1650
• Southern Italy, 1500–1700
• Southern Italy, 1300–1500
• Spanish Inquisition
• Spanish Islam, 1350-1614
• Spenser, Edmund
• Sperone Speroni
• Spinoza, Baruch
• Stampa, Gaspara
• Stuart, Elizabeth, Queen of Bohemia
• Switzerland
• Tarabotti, Arcangela
• Tasso Torquato
• Tell, William
• Teresa of Avila
• Textiles: 1400 to 1700
• The Casa of San Giorgio, Genoa
• The Radical Reformation
• The Sack of Rome (1527)
• Thirty Years War, The
• Thomas Wyatt
• Tornabuoni, Lucrezia
• Trade Networks
• Tragedy, English
• Translation
• Transylvania, The Principality of
• Traversari, Ambrogio
• Universities
• Valeriano, Pierio
• Valla, Lorenzo
• van Eyck, Jan
• van Schurman, Anna Maria
• Vasari, Giorgio
• Vega, Lope de
• Vegio, Maffeo
• Venice, Maritime
• Vergerio, Pier Paolo, The Elder
• Vermeer, Johannes
• Vernacular Languages and Dialects
• Vida, Marco Girolamo
• Virgil in Renaissance Thought
• Visitors, Italian
• Vives, Juan Luis
• Walter Ralegh
• War and Economy, 1300-1600
• Warfare and Military Organizations
• Weyden, Rogier van der
• Wolsey, Thomas, Cardinal
• Women and Learning
• Women and Medicine
• Women and Science
• Women and the Book Trade
• Women and the Reformation
• Women and the Visual Arts
• Women and Warfare
• Women and Work: Fourteenth to Seventeenth Centuries
• Women Writers in Ireland
• Women Writers of the Iberian Empire
• Women Writing in Early Modern Spain
• Women Writing in English
• Women Writing in French
• Women Writing in Italy
• Wroth, Mary
• Privacy Policy
• Cookie Policy
• Legal Notice
• Accessibility

Powered by:

• [185.66.14.133]
• 185.66.14.133

• History & Society
• Science & Tech
• Biographies
• Animals & Nature
• Geography & Travel
• Arts & Culture
• Games & Quizzes
• On This Day
• One Good Fact
• New Articles
• Lifestyles & Social Issues
• Philosophy & Religion
• Politics, Law & Government
• World History
• Health & Medicine
• Browse Biographies
• Birds, Reptiles & Other Vertebrates
• Bugs, Mollusks & Other Invertebrates
• Environment
• Fossils & Geologic Time
• Entertainment & Pop Culture
• Sports & Recreation
• Visual Arts
• Demystified
• Image Galleries
• Infographics
• Top Questions
• Britannica Kids
• Saving Earth
• Space Next 50
• Student Center
• Introduction & Top Questions
• Early life and education

Copernicus’s astronomical work

• Publication of De revolutionibus

• Why is Nicolaus Copernicus famous?
• What did Nicolaus Copernicus do for a living?
• How did Nicolaus Copernicus influence others?
• What does Earth look like?
• What is the Scientific Revolution?

Our editors will review what you’ve submitted and determine whether to revise the article.

• Wolfram Research - Eric Weisstein's World of Scientific Biography - Biography of Nicholaus Copernicus
• Encyclopædia Iranica - Biography of Edward Fitzgerald
• Khan Academy - Nicolaus Copernicus
• Space.com - Nicolaus Copernicus biography: Facts & discoveries
• World History Encyclopedia - Nicolaus Copernicus
• Culture.pl - Copernicus: Revelations about the Renaissance Man
• Stanford Encyclopedia of Philosophy - Biography of Nicolaus Copernicus
• University of Rochester - Department of Physics and Astronomy - The Copernican Model: A Sun-Centered Solar System
• Nicolaus Copernicus - Children's Encyclopedia (Ages 8-11)
• Nicolaus Copernicus - Student Encyclopedia (Ages 11 and up)
• Table Of Contents

The contested state of planetary theory in the late 15th century and Pico’s attack on astrology’s foundations together constitute the principal historical considerations in constructing the background to Copernicus’s achievement. In Copernicus’s period, astrology and astronomy were considered subdivisions of a common subject called the “science of the stars,” whose main aim was to provide a description of the arrangement of the heavens as well as the theoretical tools and tables of motions that would permit accurate construction of horoscopes and annual prognostications. At this time the terms astrologer , astronomer , and mathematician were virtually interchangeable; they generally denoted anyone who studied the heavens using mathematical techniques. Pico claimed that astrology ought to be condemned because its practitioners were in disagreement about everything, from the divisions of the zodiac to the minutest observations to the order of the planets. A second long-standing disagreement, not mentioned by Pico, concerned the status of the planetary models. From antiquity, astronomical modeling was governed by the premise that the planets move with uniform angular motion on fixed radii at a constant distance from their centres of motion. Two types of models derived from this premise.

Recent News

The first, represented by that of Aristotle , held that the planets are carried around the centre of the universe embedded in unchangeable, material, invisible spheres at fixed distances. Since all planets have the same centre of motion, the universe is made of nested, concentric spheres with no gaps between them. As a predictive model, this account was of limited value. Among other things, it had the distinct disadvantage that it could not account for variations in the apparent brightness of the planets since the distances from the centre were always the same.

A second tradition, deriving from Claudius Ptolemy , solved this problem by postulating three mechanisms: uniformly revolving, off-centre circles called eccentrics; epicycles , little circles whose centres moved uniformly on the circumference of circles of larger radius ( deferents ); and equants . The equant, however, broke with the main assumption of ancient astronomy because it separated the condition of uniform motion from that of constant distance from the centre. A planet viewed from the centre c of its orbit would appear to move sometimes faster, sometimes slower. As seen from Earth, removed a distance e from c, the planet would also appear to move nonuniformly. Only from the equant, an imaginary point at distance 2 e from Earth, would the planet appear to move uniformly. A planet-bearing sphere revolving around an equant point will wobble; situate one sphere within another, and the two will collide, disrupting the heavenly order. In the 13th century a group of Persian astronomers at Marāgheh discovered that, by combining two uniformly revolving epicycles to generate an oscillating point that would account for variations in distance, they could devise a model that produced the equalized motion without referring to an equant point.

The Marāgheh work was written in Arabic, which Copernicus did not read. However, he learned to do the Marāgheh “trick,” either independently or through a still-unknown intermediary link. This insight was the starting point for his attempt to resolve the conflict raised by wobbling physical spheres. Copernicus might have continued this work by considering each planet independently, as did Ptolemy in the Almagest, without any attempt to bring all the models together into a coordinated arrangement. However, he was also disturbed by Pico’s charge that astronomers could not agree on the actual order of the planets. The difficulty focused on the locations of Venus and Mercury . There was general agreement that the Moon and Sun encircled the motionless Earth and that Mars , Jupiter , and Saturn were situated beyond the Sun in that order. However, Ptolemy placed Venus closest to the Sun and Mercury to the Moon, while others claimed that Mercury and Venus were beyond the Sun.

In the Commentariolus, Copernicus postulated that, if the Sun is assumed to be at rest and if Earth is assumed to be in motion, then the remaining planets fall into an orderly relationship whereby their sidereal periods increase from the Sun as follows: Mercury (88 days), Venus (225 days), Earth (1 year), Mars (1.9 years), Jupiter (12 years), and Saturn (30 years). This theory did resolve the disagreement about the ordering of the planets but, in turn, raised new problems. To accept the theory’s premises , one had to abandon much of Aristotelian natural philosophy and develop a new explanation for why heavy bodies fall to a moving Earth. It was also necessary to explain how a transient body like Earth, filled with meteorological phenomena, pestilence, and wars, could be part of a perfect and imperishable heaven. In addition, Copernicus was working with many observations that he had inherited from antiquity and whose trustworthiness he could not verify. In constructing a theory for the precession of the equinoxes , for example, he was trying to build a model based upon very small, long-term effects. And his theory for Mercury was left with serious incoherencies.

Any of these considerations alone could account for Copernicus’s delay in publishing his work. (He remarked in the preface to De revolutionibus that he had chosen to withhold publication not for merely the nine years recommended by the Roman poet Horace but for 36 years, four times that period.) And, when a description of the main elements of the heliocentric hypothesis was first published, in the Narratio prima (1540 and 1541, “First Narration”), it was not under Copernicus’s own name but under that of the 25-year-old Georg Rheticus . Rheticus, a Lutheran from the University of Wittenberg, Germany, stayed with Copernicus at Frauenburg for about two and a half years, between 1539 and 1542. The Narratio prima was, in effect, a joint production of Copernicus and Rheticus, something of a “trial balloon” for the main work. It provided a summary of the theoretical principles contained in the manuscript of De revolutionibus, emphasized their value for computing new planetary tables, and presented Copernicus as following admiringly in the footsteps of Ptolemy even as he broke fundamentally with his ancient predecessor. It also provided what was missing from the Commentariolus : a basis for accepting the claims of the new theory.

Both Rheticus and Copernicus knew that they could not definitively rule out all possible alternatives to the heliocentric theory . But they could underline what Copernicus’s theory provided that others could not: a singular method for ordering the planets and for calculating the relative distances of the planets from the Sun. Rheticus compared this new universe to a well-tuned musical instrument and to the interlocking wheel-mechanisms of a clock. In the preface to De revolutionibus , Copernicus used an image from Horace’s Ars poetica (“Art of Poetry”). The theories of his predecessors, he wrote, were like a human figure in which the arms, legs, and head were put together in the form of a disorderly monster. His own representation of the universe, in contrast, was an orderly whole in which a displacement of any part would result in a disruption of the whole. In effect, a new criterion of scientific adequacy was advanced together with the new theory of the universe.

Nicolaus Copernicus biography: Facts & discoveries

Meet Polish astronomer Nicolaus Copernicus.

Bibliography

Nicolaus Copernicus proposed his theory that the planets revolved around the sun in the 1500s, when most people believed that Earth was the center of the universe . Although his model wasn't completely correct, it formed a strong foundation for future scientists, such as Galileo, to build on and improve humanity's understanding of the motion of heavenly bodies.

Indeed, other astronomers built on Copernicus' work and proved that our planet is just one world orbiting one star in a vast cosmos loaded with both, and that we're far from the center of anything.

Countdown: The most famous astronomers of all time

Born on Feb. 19, 1473, in Toruń, Poland, Mikolaj Kopernik (Copernicus is the Latinized form of his name) traveled to Italy to attend college, according to the Encyclopedia Britannica . Copernicus' father had died when the child was young, and his uncle became a leading figure in his life.

Copernicus' uncle wanted him to study the laws and regulations of the Catholic Church then return home to become a canon, a type of official in the Catholic Church.

However, while visiting several academic institutions, Copernicus spent most of his time studying mathematics and astronomy . While attending the University of Bologna, Copernicus lived and worked with astronomy professor Domenico Maria de Novara, doing research and helping him make observations of the heavens.

Due to his uncle's influence, Copernicus did become a canon in Warmia, in northern Poland, although he never took orders as a priest. He conducted his astronomical research in between his duties as canon, the Encyclopedia Britannica noted.

The Copernican model of the solar system

In Copernicus' lifetime, most believed that Earth held its place at the center of the universe. The sun, the stars , and all of the planets revolved around it.

One of the glaring mathematical problems with this model was that the planets, on occasion, would travel backward across the sky over several nights of observation. Astronomers called this retrograde motion . To account for it, the current model, based on the Greek astronomer and mathematician Ptolemy's view, incorporated a number of circles within circles — epicycles — inside of a planet's path. Some planets required as many as seven circles, creating a cumbersome model many felt was too complicated to have naturally occurred.

In 1514, Copernicus distributed a handwritten book to his friends that set out his view of the universe. In it, he proposed that the center of the universe was not Earth, but that the sun lay near it. He also suggested that Earth's rotation accounted for the rise and setting of the sun, the movement of the stars, and that the cycle of seasons was caused by Earth's revolutions around it. 

Finally, he (correctly) proposed that Earth's motion through space caused the retrograde motion of the planets across the night sky (planets sometimes move in the same directions as stars, slowly across the sky from night to night, but sometimes they move in the opposite, or retrograde, direction).

Copernicus finished the first manuscript of his book, "De Revolutionibus Orbium Coelestium" (" On the Revolutions of the Heavenly Spheres ") in 1532. In it, Copernicus established that the planets orbited the sun rather than the Earth. He laid out his model of the solar system and the path of the planets. 

– Galileo Galilei: Biography, inventions & other facts

– How did the solar system form?

– Parker Solar Probe: Mission to touch the sun

– Red giant stars: Facts, definition & the future of the sun

He didn't publish the book, however, until 1543, just two months before he died. He diplomatically dedicated the book to Pope Paul III. The church did not immediately condemn the book as heretical, perhaps because the printer added a note that said even though the book's theory was unusual, if it helped astronomers with their calculations, it didn't matter if it wasn't really true. It probably also helped that the subject was so difficult that only highly educated people could understand it. The Church did eventually ban the book in 1616, according to Physics Today .

The Catholic Church wasn't the only Christian faith to reject Copernicus' idea.

"When 'De Revolutionibus Orbium Coelestium' was published in 1543, religious leader Martin Luther voiced his opposition to the heliocentric solar system model," says Biography.com . "His underling, Lutheran minister Andreas Osiander, quickly followed suit, saying of Copernicus, 'This fool wants to turn the whole art of astronomy upside down.'"

Copernicus died on May 24, 1543, of a stroke. He was 70. 

Where was Copernicus buried?

In 2008, researchers announced that a skull found in Frombork Cathedral did belong to the astronomer, according to The Guardian . By matching DNA from the skull to hairs found in books once owned by Copernicus, the scientists confirmed the identity of the astronomer. Polish police then used the skull to reconstruct how its owner might have looked. 

Nature quotes the AFP as stating that the reconstruction "bore a striking resemblance to portraits of the young Copernicus."

In 2010, his remains were blessed with holy water by some of Poland's highest-ranking clerics before being reburied, his grave marked with a black granite tombstone decorated with a model of the solar system. The tomb marks both his scientific contribution and his service as church canon.

"Today's funeral has symbolic value in that it is a gesture of reconciliation between science and faith," Jacek Jezierski, a local bishop who encouraged the search for Copernicus, said according to the Associated Press . "Science and faith can be reconciled."

The unmarked grave was not linked to suspicions of heresy, as his ideas were only just being discussed and had yet to be forcefully condemned, according to Jack Repcheck, author of " C opernicus' Secret: How the Scientific Revolution Began ."

"Why was he just buried along with everyone else, like every other canon in Frombork?" Repcheck said. "Because at the time of his death he was just any other canon in Frombork. He was not the iconic hero that he has become."

Refining the work of Copernicus

Although Copernicus' model changed the layout of the universe, it still had its faults. For one thing, Copernicus held to the classical idea that the planets traveled in perfect circles. It wasn't until the 1600s that Johannes Kepler proposed the orbits were instead ellipses. As such, Copernicus' model featured the same epicycles that marred Ptolemy's work, although there were fewer.

Copernicus' ideas took nearly a hundred years to seriously take hold. When Galileo Galilei claimed in 1632 that Earth orbited the sun, building upon the Polish astronomer's work, he found himself under house arrest for committing heresy against the Catholic Church. 

Despite this, the observations of the universe proved the two men correct in their understanding of the motion of celestial bodies. Today, we call the model of the solar system, in which the planets orbit the sun, a heliocentric or Copernican model.

"Sometimes Copernicus is honored as having substituted the old geocentric system with the new, heliocentric one, as having regarded the sun, instead of the Earth, as the unmoving center of the universe," Konrad Rudnicki, an astronomer and author of " The Cosmological Principles ," wrote. "This view, while quite correct, does not render the actual significance of Copernicus's work."

According to Rudnicki, Copernicus went beyond simply creating a model of the solar system.

"All his work involved a new cosmological principle originated by him. It is today called the Genuine Copernican Cosmological Principle and says, 'The Universe as observed from any planet looks much the same,'" Rudnicki wrote.

So while Copernicus' model physically placed the sun at the center of the solar system, it also figuratively removed the focus from Earth, making it just another planet.

Additional resources

You can read the English translation of Copernicus' manuscript "De Revolutionibus Orbium Cœlestium" here . Check out the complete works of Nicholas Copernicus Complete in " On the Revolutions: Nicholas Copernicus Complete Works (Foundations of Natural History) ". Also, discover the many artefacts at the British Museum regarding Nicolaus Copernicus, here .

Jack Repcheck, " Copernicus' Secret: How the Scientific Revolution Began ," Simon & Schuster, 2008. 

Sheila Rabin, " Nicolaus Copernicus ," The Stanford Encyclopedia of Philosophy, 2019.

Fred Hoyle, "The work of Nicolaus Copernicus," Proceedings of the Royal Society A, Volume 336, January 1974, https://doi.org/10.1098/rspa.1974.0009 .

Teresa Zielinska, "Nicolaus Copernicus (1473–1543)," Distinguished Figures in Mechanism and Machine Science, History of Mechanism and Machine Science Volume 1, 2007, https://doi.org/10.1007/978-1-4020-6366-4_5 

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

Get the Space.com Newsletter

Breaking space news, the latest updates on rocket launches, skywatching events and more!

Nola Taylor Tillman is a contributing writer for Space.com. She loves all things space and astronomy-related, and enjoys the opportunity to learn more. She has a Bachelor’s degree in English and Astrophysics from Agnes Scott college and served as an intern at Sky & Telescope magazine. In her free time, she homeschools her four children. Follow her on Twitter at @NolaTRedd

Just how dark is the universe? NASA's New Horizons probe gives us best estimate yet

UAE on track to launch bold 7-asteroid mission in 2028

Polaris Dawn crew flies higher than 1966 Gemini 11 orbital record

Most Popular

• 2 Watch 1st look clip from 'Star Trek: Lower Decks' Season 5 (video)
• 3 Space MacGyver: NASA astronaut and inventor Don Pettit eager to return to ISS on Sept. 11
• 4 These 2 monster black holes may be the closest pair ever discovered (video)
• 5 Legendary actor and 'Star Wars'' voice of Darth Vader, James Earl Jones dies at 93

CERN Accelerating science

The Copernican Revolution, and how it almost became unnoticed and forgotten

Go to Indico Event

Where:  

​The Copernican Revolution — the heliocentric model of the Universe introduced by Nicolaus Copernicus — is considered as one of the most significant achievements in the history of science. And yet, it luckily happened despite many obstacles and even then it could have become unnoticed and forgotten. The year 2023 marked the 550th anniversary of the birth of Nicolaus Copernicus which gave us additional motivation to have a closer look at his highly extraordinary life and achievement.

Professor Roszkowski works in the fields of elementary particle physics, particle astrophysics and particle cosmology. In particle physics he is mainly interested in models of “new physics” beyond the Standard Model, like supersymmetry, especially the recently discovered Higgs boson and new yet unseen particles whose traces are searched for at the LHC and in other collider experiments. In particle astrophysics he is mainly interested in the puzzle of the identity of dark matter and in elementary particle models of new physics providing its solution. In particle cosmology he works on implications of new physics for the properties and evolution of the early Universe.

Coffee and tea served at 16:00pm

Other Events

The copernican revolution, and how it almost became unnoticed and fo....

• Skip to primary navigation
• Skip to main content
• Skip to primary sidebar

• FREE Experiments
• Kitchen Science
• Climate Change
• Egg Experiments
• Fairy Tale Science
• Edible Science
• Human Health
• Inspirational Women
• Forces and Motion
• Science Fair Projects
• STEM Challenges
• Science Sparks Books
• Contact Science Sparks
• Science Resources for Home and School

Who was Nicolaus Copernicus? – Theory of Heliocentrism

November 19, 2017 By Emma Vanstone Leave a Comment

Nicolaus Copernicus was a Polish astronomer born in February 1473 who realised that the Earth orbits the Sun. This idea was strongly opposed at the time as many people believed objects orbited around a central Earth.

The model proposed by Copernicus was called Heliocentrism.

What is Heliocentrism?

Heliocentrism ( helios means Sun ) is where the Sun is motionless at the centre with other planets rotating around it in circular paths. We now know that this is absolutely how things work, and it seems very obvious, but Copernicus didn’t have the tools we have today. His ideas marked the beginning of modern astronomy.

Facts about Nicolaus Copernicus

• Copernicus was also a physician, scholar, economist, translator, mathematician and artist!
• Nicolaus Copernicus was born on February 19th 1473.
• His theory of Heliocentrism was proposed in his book De revolutionibus orbium coelestium
• The chemical element Copernicum (symbol Cn and atomic number 112 ) is named after Copernicus.
• Nicolaus Copernicus was one of the great polymaths of his time. A polymath is someone brilliant at lots of different things. Aristotle, Archimedes and Leonardo Da Vinci were also great polymaths.

This easy activity helps children visualise how the Sun, Earth and Moon move around each other to demonstrate Nicolaus Copernicus’s theory.

Heliocentrism Activity for Kids

Black cardboard

Yellow, blue and grey paper or card

Instructions

You’ll need three children to take part in the demonstration. One will be the Sun, one the Moon and one the Earth.

Make three hats to represent the Sun, Earth and Moon using cardboard and a stapler or glue.

Ask the Sun to stand in the centre and the Earth to walk around the Sun in a circle. The Moon should then walk around the Earth in a circle as the Earth circles the Sun.

More Heliocentrism Ideas

How many other planets can you add to your demonstration?

Try thinking about how long it takes the Moon to orbit the Earth and how long it takes the Earth to orbit the Sun and ask the children to change their walking speed to reflect this.

Create a moving model of the Sun and Earth to show how the Earth orbits around the Sun.

If you enjoyed this activity, don’t forget to look at my other solar system activity ideas .

If you want to discover more science activities based around the discoveries of famous scientists we have those too!

Last Updated on January 11, 2024 by Emma Vanstone

Safety Notice

Science Sparks ( Wild Sparks Enterprises Ltd ) are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources. Science Sparks assume no liability with regard to injuries or damage to property that may occur as a result of using the information and carrying out the practical activities contained in this resource or in any of the suggested further resources.

These activities are designed to be carried out by children working with a parent, guardian or other appropriate adult. The adult involved is fully responsible for ensuring that the activities are carried out safely.

Reader Interactions

Leave a reply cancel reply.

Your email address will not be published. Required fields are marked *

Nicolaus Copernicus and the Heliocentric Model

Nicolaus Copernicus(1473 – 1543)

On February 19 , 1473 , Renaissance mathematician and astronomer Nicolaus Copernicus  was born, who established the heliocentric model , which placed the Sun , rather than the Earth , at the center of the universe. With the publication of his research he started the so-called Copernican Recolution , which started a paradigm shift away from the former Ptolemaic model of the heavens, which postulated the Earth at the center of the universe, towards the heliocentric model with the Sun at the center of our Solar System. In 1543 Nicolaus Copernicus published his treatise  De revolutionibus orbium coelestium ( On the Revolutions of the Heavenly Spheres ), which presented a heliocentric model view of the universe. Overall, it took about 200 years for a heliocentric model to replace the Ptolemaic model. But, Copernicus was not the first to propose a heliocentric model. Actually, even the ancient Greek philosophers argued about, as e.g. Aristarchus of Samos in the 3rd century BCE,[ 6 ] who had developed some theories of Heraclides Ponticus (speaking of a revolution by Earth on its axis) to propose what was, so far as is known, the first serious model of a heliocentric solar system.

“Finally we shall place the Sun himself at the center of the Universe. All this is suggested by the systematic procession of events and the harmony of the whole Universe, if only we face the facts, as they say, “with both eyes open.” — Nicolaus Copernicus,  De revolutionibus orbium coelestium (1543), as quoted in [15 ]

Nicolaus Copernicus – Early Years

Nicolaus Copernicus was born in the city of Thorn (modern Toruń), in the province of Royal Prussia, in the Crown of the Kingdom of Poland, as the son of successful merchants. He was well educated, speaking Latin, German, and Polish fluently, wherefore most of his later publications were published in Latin. In 1491, Copernicus began his studies at the University of Krakow gathering the basic knowledge in mathematics and astronomy. Besides his astronomical interests, Copernicus evolved a great interest in the philosophical ideas of Aristotle , works by Euclid ,[ 7 ] or Johannes Regiomontanus ‘ Tabulae directionum , gathering a great private library.[ 8 ] Even though the time at Krakow University was important to his future career in concerns of his knowledge and experience, he left the institution without a degree.

Neoplatonism and Astronomy in Bologna

In 1495 Copernicus was appointed canon of the cathedral school in Frauenburg. His uncle Watzenrode sent him to the University of Bologna, where he began to study law in the winter semester of 1496/1497, but did not yet earn an academic degree. In Bologna Copernicus studied Greek with Urceus Codrus and astronomy with Domenico Maria da Novara, who taught him new theories on the movement of planets. There he acquired the title of Magister artium. Novara introduced him to the world of thought of Neoplatonism , for which the sun was of great importance as the material image of God or the One.

Rome, Padua and Ferrara

In 1500 Copernicus left Bologna and spent some time in Rome on the occasion of the Holy Year before returning to Frauenburg in Warmia in 1501. He asked for permission to extend his studies in Italy and began studying medicine at the University of Padua that same year. At the same time he continued his law studies. Copernicus received his doctorate in Canon Law ( Doctor iuris canonici ) from the University of Ferrara on 31 May 1503. He did not obtain an academic degree in medicine.

The Warmia Canonry

In 1503 he returned to Warmia and began working as a secretary and doctor for his uncle Lucas Watzenrode, the prince-bishop of Warmia. Copernicus became a doctor and his uncle got a job at the canonry in Frauenburg. Despite the difficult situation in Prussia, where towns and people fought for and against the Catholic government, Watzenrode, as prince-bishop and sovereign of the country, and his nephew Copernicus were able to preserve the independence of Warmia from the Order and the self-governing powers of the Polish Crown. Copernicus was elected Chancellor of the Warmia Canonry  in 1510, 1519, 1525 and 1528. In the armed conflicts between the Teutonic Order and Poland, Copernicus, like his uncle, represented the side of the Prussian Federation, which was allied with Poland against the Teutonic Order.

Heliocentric model from Nicolaus Copernicus’ De revolutionibus orbium coelestium

The Heliocentric Model

The work on the heliocentric theory began during Copernicus’ time as his uncles’ secretary in Heilsberg. Nicolaus Copernicus had already made his ideas accessible to a small circle of experts around 1509 with the Commentariolus . He wrote in it that the mathematical details still had to be worked out.  In his brief foreword, Copernicus first praised the theory of homocentric spheres created by Eudoxos of Cnidus and further developed by Callippus of Cyzicus, which made it possible to describe the irregular movements of the planets observed in the sky by means of compound regular circular movements. At the same time, however, he complained that they were not sufficiently consistent with the results of the observations. The epicyclic theory of Claudius Ptolemy attested Copernicus a good prediction of the position of the planets in the sky, but did not agree with its task of regularity of planetary motion.

Copernicus attributed his considerations on how to save a perfectly uniform circular motion of the planets to the following “principles” listed after the preface (here only the first three):

• For all heavenly circles or spheres there is not only one centre.
• The center of the earth is not the center of the world, but only the center of gravity and the moon’s orbit.
• All orbits surround the sun as if it were in the middle, and therefore the center of the world is near the sun.

However, it was not intended to be published at any time. Only few fellow astronomers were supposed to read and contribute to his ideas. Nothing is known about the distribution of Commentariolus during Copernicus’ lifetime and its influence on contemporary astronomy. In Tycho Brahe ‘s 1602 published work Astronomiae Instauratae Progymnasmata  a short reference to the Commentariolus can be found.

Sheet 34 of the manuscript 10530 from the Austrian National Library with the title Nicolai Copernici de hypothesibus motuum coelestium a se constitutis commentariolus

De Revolutionibus Orbium Coelestium

Around 1512 Pope Leo X presented the possible calendar reform for discussion. Since the mean length of a year in the Julian calendar did not correspond exactly to that of a solar year, the date of the winter solstice had shifted in the course of the centuries by ten days. The Frauenburg canon Nicolaus Copernicus said that astronomical theory had to be corrected before the question of calendar reform could be addressed.[17] The manuscript of De revolutionibus orbium coelestium held Copernicus back for a long time. It is believed that he was either afraid to ridicule himself with such an absurd theory or that he felt it was not opportune to reveal such secrets. In 1538 Johannes Schöner [ 10 ] and Johannes Petreius commissioned Georg Joachim Rheticus ,[ 11 ] who was in Nuremberg for a study visit, to visit Copernicus in Frauenburg and persuade him to have his work printed. Rheticus stayed with Copernicus from 1539 to 1541. In 1540 he announced the ideas of Copernicus in the Narratio Prima . Finally he succeeded in persuading Copernicus to print and publish De revolutionibus . Andreas Osiander  added an anonymous foreword to the manuscript, according to which the heliocentric world view does not have to be true or plausible, but merely has the benefit of simplifying astronomical calculations. Johannes Kepler exposed Osiander’s “falsification” by means of notes in the copy of the Nuremberg astronomer Hieronymus Schreiber.

Contemporary Criticism

One of the first to neglect Copernicus’ heliocentric theory was the Catholic Church’s chief censor. Others rejected the thought of mathematical physics, unable to foresee that Copernicus’ theory would change the field of physics back then critically. Theologians rejected the new world view because in some places it contradicted the Bible. In this context, it is often quoted that Martin Luther , who, after a common translation, called Copernicus a “fool”, had an absurd idea of the movement of the earth, which the biblical passage Joshua 10, 12-13 would oppose. However, protestant reformer  Philip Melanchthon eventually saw the theory’s importance and the need to teach those wherefore the University of Wittenberg became a center where the heliocentric system was to be studied. Tycho Brahe, one of the greatest astronomers before the invention of the telescope appreciated Copernicus’ efforts, but rejected his system, wherefore he developed his own called the ‘geoheliostatic’ system in which the two inner planets revolved around the sun and that system along with the rest of the planets revolved around the Earth.

Legacy and Death

On the long run, Copernicus’ system was widely accepted and caused the so called ‘Copernican Revolution’, a now often used metaphor supporting modern developments. Toward the close of 1542, Nicolaus Copernicus was seized with apoplexy and paralysis, and he died at age 70 on 24 May 1543. Legend has it that he was presented with the final printed pages of his Dē revolutionibus orbium coelestium on the very day that he died, allowing him to take farewell of his life’s work. He is reputed to have awoken from a stroke-induced coma, looked at his book, and then died peacefully.

It was only when Galileo Galilei advocated the heliocentric world view that the Inquisition, under the leadership of Robert Bellarmin , became interested in the work. He considered it dangerous to place the human mind above the divine power and the wording of the Bible, as long as it was not proven that the Bible was wrong. It was, however, a letter published in 1615 by the Carmelite theologian Paolo Antonio Foscarini (1565-1616), in which this Copernicus’s view of the world tried to reconcile with the views of the Church, which led to De revolutionibus orbium coelestium being suspended from the Index Congregation in a decree of 5 March 1616. In 1620, the Index Congregation demanded twelve corrections to the work, in the sense that the hypothesis character of the theory was emphasized. If these corrections were made, however, the use of the work was still permitted.

References and Further Reading:

• [1] Nicolaus Copernicus at Stanford
• [2] Nicolaus Copernicus at NASA
• [4] Nicolaus Copernicus at Space.com
• [5] The Galileo Affair   , SciHi Blog
• [6]  Aristarchus of Samos – Putting the Sun at the Right Place , SciHi Blog
• [7]  Euclid – the Father of Geometry , SciHi blog
• [8]  Regiomontanus – Forerunner of Modern Astronomy , SciHi Blog
• [9] Tycho Brahe – The Man with the Golden Nose , SciHi Blog
• [10]  Johannes Schöner and his Globes , SciHi Blog
• [11]  Georg Joachim Rheticus’ Achievements for Astronomy , SciHi Blog
• [12]  And Kepler Has His Own Opera – Kepler’s 3rd Planetary Law , SciHi Blog
• [13] Nicolaus Copernicus at Wikidata
• [14]  ASTR 302 Lecture 2: The Copernican Revolution , Rob Park @ youtube
• [15] Thomas S. Kuhn, The Copernican Revolution : Planetary Astronomy in the Development of Western Thought (1957)
• [16]  O’Connor, John J.;   Robertson, Edmund F.,   “Nicolaus Copernicus” ,   MacTutor History of Mathematics archive ,   University of St Andrews .
• [17]  Copernicus and the Calendar , The Renaissance Mathematicus, Oct 28, 2014.
• [18] Science contra Copernicus , The Renaissance Mathematicus, Oct 7, 2015.
• [19]  Timeline for Nicolaus Copernicus , via Wikidata

Harald Sack

Related posts, karl pearson and mathematical statistics, conrad gessner’s truly renaissance knowledge, august leopold crelle and his journal, john herschel – a pioneer in celestial photography, one comment.

Pingback: Heliocentric vs. Geocentric Blog Post #4 – Joliet Junior College – Astronomy 101 class blog

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Further Projects

• February (28)
• January (30)
• December (30)
• November (29)
• October (31)
• September (30)
• August (30)
• January (31)
• December (31)
• November (30)
• August (31)
• February (29)
• February (19)
• January (18)
• October (29)
• September (29)
• February (5)
• January (5)
• December (14)
• November (9)
• October (13)
• September (6)
• August (13)
• December (3)
• November (5)
• October (1)
• September (3)
• November (2)
• September (2)

Legal Notice

• Privacy Statement

Thought Experiments in Ancient Greece

• First Online: 20 May 2016

Cite this chapter

• Friedel Weinert 2  

960 Accesses

Image an ancient Greek who is exercised by questions of cosmic import: Is the universe finite or infinite? Is the Earth spherical or flat? Is the Earth the centre of the universe or does it rotate around a different hub, say the sun?

It is not so much the particular form that scientific theories have now taken – the conclusions which we believe we have proved – as the movement of thought behind them that concerns the philosopher. Eddington, The Nature of the Physical World (1932: 353)

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Subscribe and save.

• Get 10 units per month
• Download Article/Chapter or eBook
• 1 Unit = 1 Article or 1 Chapter
• Cancel anytime
• Available as PDF
• Read on any device
• Instant download
• Own it forever
• Available as EPUB and PDF
• Compact, lightweight edition
• Dispatched in 3 to 5 business days
• Free shipping worldwide - see info
• Durable hardcover edition

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Author information

Authors and affiliations.

Faculty of Social Sciences, University of Bradford, Bradford, UK

Friedel Weinert

You can also search for this author in PubMed   Google Scholar

Corresponding author

Correspondence to Friedel Weinert .

Rights and permissions

Reprints and permissions

Copyright information

© 2016 Springer International Publishing Switzerland

About this chapter

Weinert, F. (2016). Thought Experiments in Ancient Greece. In: The Demons of Science. Springer, Cham. https://doi.org/10.1007/978-3-319-31708-3_2

Download citation

DOI : https://doi.org/10.1007/978-3-319-31708-3_2

Published : 20 May 2016

Publisher Name : Springer, Cham

Print ISBN : 978-3-319-31707-6

Online ISBN : 978-3-319-31708-3

eBook Packages : Physics and Astronomy Physics and Astronomy (R0)

Share this chapter

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

• Publish with us

Policies and ethics

• Find a journal
• Track your research

Nicolaus Copernicus

Nicolaus Copernicus (1473-1543) was a mathematician and astronomer who proposed that the sun was stationary in the center of the universe and the earth revolved around it. Disturbed by the failure of Ptolemy's geocentric model of the universe to follow Aristotle's requirement for the uniform circular motion of all celestial bodies and determined to eliminate Ptolemy's equant, an imaginary point around which the bodies seemed to follow that requirement, Copernicus decided that he could achieve his goal only through a heliocentric model. He thereby created a concept of a universe in which the distances of the planets from the sun bore a direct relationship to the size of their orbits. At the time Copernicus's heliocentric idea was very controversial; nevertheless, it was the start of a change in the way the world was viewed, and Copernicus came to be seen as the initiator of the Scientific Revolution.

1. Life and Works

2.1 pre-copernican astronomy, 2.2 the commentariolus, 2.3 on the revolutions, 2.4 rheticus and the narratio prima, 2.5 printing on the revolutions and osiander's preface, 2.6 sixteenth century reactions to on the revolutions, bibliography, other internet resources, related entries.

Nicolaus Copernicus was born on 19 February 1473, the youngest of four children of Nicolaus Copernicus, Sr., a well-to-do merchant who had moved to Torun from Cracow, and Barbara Watzenrode, the daughter of a leading merchant family in Torun. The city, on the Vistula River, was an important inland port in the Hanseatic League. Fighting between the Order of the Teutonic Knights and the Prussian Union in alliance with the Kingdom of Poland ended in 1466, and West Prussia, which including Torun, was ceded to Poland. Thus the child of a German family was a subject of the Polish crown.

The father died in 1483, and the children's maternal uncle, Lucas Watzenrode (1447-1512), took them under his protection. Watzenrode was a very successful cleric — he was to become bishop of Warmia (Ermland in German) in 1489 — and he both facilitated his nephew's advancement in the church and directed his education. In 1491 Copernicus enrolled in the University of Cracow. There is no record of his having obtained a degree, which was not unusual at the time as he did not need a bachelor's degree for his ecclesiastical career or even to study for a higher degree. But the University of Cracow offered courses in mathematics, astronomy, and astrology, and Copernicus's interest was sparked, which is attested to by his acquisition of books in these subjects while at Cracow. [ 1 ]

In 1495 Watzenrode arranged Copernicus's election as canon of the chapter of Frombork (Frauenberg in German) of the Cathedral Chapter of Warmia, an administrative position just below that of bishop. He assumed the post two years later, and his financial situation was secure for life. In the meantime, following in his uncle's footsteps, Copernicus went to the University of Bologna in 1496 to study canon law. While at Bologna he lived with the astronomy professor Domenico Maria Novara and made his first astronomical observations. In addition, as Rosen (1971, 323) noted, “In establishing close contact with Novara, Copernicus met, perhaps for the first time in his life, a mind that dared to challenge the authority of [Ptolemy] the most eminent ancient writer in his chosen fields of study.” Copernicus also gave a lecture on mathematics in Rome, which may have focused on astronomy.

Copernicus's studies at Bologna provided an advantage he did not have at Cracow — a teacher of Greek. Humanism began to infiltrate the Italian universities in the fifteenth century. As Grendler (510) remarked, “By the last quarter of the century, practically all universities had one or several humanists, many of them major scholars.” Antonio Cortesi Urceo became professor at Bologna in 1482 and added Greek several years later. Copernicus may have studied with him, for Copernicus translated into Latin the letters of the seventh-century Byzantine author Theophylactus Simocatta ( MW 27-71) from the 1499 edition of a collection of Greek letters produced by the Venetian humanist printer Aldus Manutius. Aldus had dedicated his edition to Urceo. Copernicus had his translation printed in 1509, his only publication prior to the On the Revolutions ( De revolutionibus ). It is important to note that Copernicus's acquisition of a good reading knowledge of Greek was critical for his studies in astronomy because major works by Greek astronomers, including Ptolemy, had not yet been translated into Latin, the language of the universities at the time.

Copernicus left Bologna for Frombork in 1501 without having obtained his degree. The chapter then approved another leave of absence for Copernicus to study medicine at the University of Padua. The medical curriculum did not just include medicine, anatomy, and the like when Copernicus studied it. Siraisi (1990, 16) noted that “the reception in twefth-century western Europe of Greek and Islamic technical astronomy and astrology fostered the development of medical astrology…the actual practice of medical astrology was greatest in the West between the fourteenth and the sixteenth centuries.” Astrology was taught in the medical schools of Italy. “The importance attached to the study of the stars in medieval medical education derived from a general and widely held belief that the heavenly bodies play an intermediary role in the creation of things here below and continue to influence them throughout their existence. The actual uses of astrology in medical diagnosis and treatment by learned physicians were many and various. ‘Astrological medicine’ is a vague and unsatisfactory term that can embrace any or all of the following: first, to pay attention to the supposed effect of astrological birth signs or signs at conception on the constitution and character of one's patients; second, to vary treatment according to various celestial conditions…third, to connect the doctrine of critical days in illness with astrological features, usually phases of the moon; and fourth, to predict or explain epidemics with reference to planetary conjunctions, the appearance of comets, or weather conditions” (Siraisi, 1981, 141-42). It is true that astrology required that medical students acquire some grounding in astronomy; nevertheless, there is no doubt that Copernicus studied astrology while at the University of Padua. [ 2 ]

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 (Heilsberg in German). Although he made some astronomical observations, he was immersed in church politics, and after his elderly uncle became ill in 1507, Copernicus was his attending physician. Rosen (1971, 334-35) 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 interfered with his continuing pursuit of his studies in astronomy. He took up residence in his chapter of Frombork in 1510 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 176-215) 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 1520-1525. He was physician for the bishop (his uncle had died in 1512) 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 1510 and 1514 he wrote an essay that has come to be known as the Commentariolus ( MW 75-126) 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 the Revolutions . He also wrote what is known as Letter against Werner ( MW 145-65) in 1524, a critique of Johann Werner's “Letter concerning the Motion of the Eighth Sphere” ( De motu octavae sphaerae tractatus primus ). Copernicus claimed that Werner erred in his calculation of time and his belief that before Ptolemy the movement of the fixed stars was uniform, but Copernius's letter did not refer to his cosmological ideas.

In 1539 a young mathematician named Georg Joachim Rheticus (1514-1574) 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. He published an introduction to Copernicus's ideas, the Narratio prima (First Report). Most importantly, he convinced Copernicus to publish On the Revolutions . Rheticus oversaw most of the printing of the book, and on 24 May 1543 Copernicus held a copy of the finished work on his deathbed.

2. Astronomical Ideas and Writings

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. The physical elements, according to Aristotle moved vertically, depending on their ‘heaviness’ or ‘gravity’; the celestial bodies were not physical but a ‘fifth element’ or ‘quintessence’ whose nature was to move in perfect circles around the earth, making a daily rotation. Aristotle envisioned the earth as the true center of all the circles or ‘orbs’ carrying the heavenly bodies around it and all motion as ‘uniform,’ that is, unchanging.

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. The most obvious problem was that the outer planets seemed to stop, move backwards in ‘retrograde’ motion for a while, and then continue forwards. By the second century, when Ptolemy compiled his Almagest (this common name of Ptolemy's Syntaxis was derived from its Arabic title), astronomers had developed the concept that the orbit moves in ‘epicycles’ around a ‘deferrent,’ that is, they move like a flat heliacal coil around a circle around the earth. The earth was also off-center, on an ‘eccentric,’ as the heavenly bodies moved around a central point. Ptolemy added a point on a straight line opposite the eccentric, which is called the ‘equalizing point’ or the ‘equant,’ and around this point the heavenly bodies moved uniformly. Moreover, unlike the Aristotelian model, Ptolemy's Almagest did not describe a unified universe. The ancient astronomers who followed Ptolemy, however, were not concerned if his system did not describe the ‘true’ motions of the heavenly bodies; their concern was to ‘save the phenomena,’ that is, give a close approximation of where the heavenly bodies would be at a given point in time. 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. [ 3 ]

During the European Middle Ages, the Islamic world was the center of astronomical thought and activity. During the ninth century several aspects of Ptolemy's solar theory were recalculated. Ibn al-Haytham in the tenth-eleventh century wrote a scathing critique of Ptolemy's work: “Ptolemy assumed an arrangement that cannot exist, and the fact that this arrangement produces in his imagination the motions that belong to the planets does not free him from the error he committed in his assumed arrangement, for the existing motions of the planets cannot be the result of an arrangement that is impossible to exist” (quoted in Rosen 1984, 174). Swerdlow and Neugebauer (46-48) stressed that the thirteenth-century Maragha school was also important in finding errors and correcting Ptolemy: “The method of the Maragha planetary models was to break up the equant motion in Ptolemy's models into two or more components of uniform circular motion, physically the uniform rotation of spheres, that together control the direction and distance of the center of the epicycle, so that it comes to lie in nearly the same position it would have in Ptolemy's model, and always moves uniformly with respect to the equant.” They found many devices used by Copernicus similar to those used by various Maragha astronomers [ 4 ] and noted that their ideas could have entered fifteenth-century Italy through Byzantine scholars.

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. Georg Peurbach (1423-1461) and (Johannes Müller) Regiomontanus (1436-1476) studied Greek for the purpose of producing an outline of Ptolemaic astronomy. By the time Regiomontanus finished the work in 1463, it was an important commentary on the Almagest as well, pointing out, for example, that Ptolemy's lunar theory did not accord with observations. 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. At the time, moreover, there was active debate over Ptolemy's deviations from Aristotle's requirement of uniform circular motion.

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 1500. Further, Corvinus, who helped him print his Latin translation in 1508-09, expressed admiration for his knowledge of astronomy, so that Copernicus's concept may have still been traditional at this point. His first heliocentric writing was his Commentariolus . It was a small manuscript that was circulated but never printed. We do not know when he wrote this, but a professor in Cracow cataloged his books in 1514 and made reference to a “manuscript of six leaves expounding the theory of an author who asserts that the earth moves while the sun stands still” (Rosen, 1971, 343; MW 75). Thus, Copernicus probably adopted the heliocentric theory sometime between 1508 and 1514. Rosen (1971, 345) suggested that Copernicus's “interest in determining planetary positions in 1512-1514 may reasonably be linked with his decisions to leave his uncle's episcopal palace in 1510 and to build his own outdoor observatory in 1513.” In other words, it was the result of a period of intense concentration on cosmology that was facilitated by his leaving his uncle and the attendant focus on church politics and medicine.

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. His only astronomical writings were the Commentariolus , the Letter against Werner , and On the Revolutions ; he published his translation of Theophylactus's letters and wrote the various versions of his treatise on coinage; other writings relate to diocesan business, as do most of the few letters that survive. Sadly, the biography by Rheticus, which should have provided scholars with an enormous amount of information, has been lost. Therefore, many of the answers to the most interesting questions about Copernicus's ideas and works have been the result of conjecture and inference, and we can only guess why Copernicus adopted the heliocentric system.

Most scholars believe that the reason Copernicus rejected Ptolemaic cosmology was because of Ptolemy's equant. [ 5 ] They assume this because of what Copernicus wrote in the Commentariolus :

Yet the widespread [planetary theories], advanced by 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 they also conceived certain equalizing circles, which made the planet appear to move at all times with uniform velocity neither on its deferent sphere nor about its own [epicycle's] center…Therefore, 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 irregularity would be derived while everything in itself would move uniformly, as is required by the rule of perfect motion” ( MW 81).

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. [ 6 ] Nor should we attribute Copernicus's desire for uniform circular motions to an aesthetic need, for this idea was philosophical not aesthetic, and Copernicus's replacing the equant with epicyclets made his system more complex than Ptolemy's. Most importantly, we should bear in mind what Swerdlow and Neugebauer (59) asserted:

Copernicus arrived at the heliocentric theory by a careful analysis of planetary models — and as far as is known, he was the only person of his age to do so — and if he chose to adopt it, he did so on the basis of an equally careful analysis.

In the Commentariolus Copernicus listed assumptions that he believed solved the problems of ancient astronomy. He stated that the earth is only the center of gravity and center of the moon's orbit; that all the spheres encircle the sun, which is close to the center of the universe; that the universe is much larger than previously assumed, and the earth's distance to the sun is a small fraction of the size of the universe; that the apparent motion of the heavens and the sun is created by the motion of the earth; and that the apparent retrograde motion of the planets is created by the earth's motion. 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.

The Commentariolus was only intended as an introduction to Copernicus's ideas, and he wrote “the mathematical demonstrations intended for my larger work should be omitted for brevity's sake…” ( MW 82). In a sense it was an announcement of the greater work that Copernicus had begun. The Commentariolus was never published during Copernicus's lifetime, but he sent manuscript copies to various astronomers and philosophers. He received some discouragement because the heliocentric system seemed to disagree with the Bible, but mostly he was encouraged. Although Copernicus's involvement with official attempts to reform the calendar was limited to a no longer extant letter, that endeavor made a new, serious astronomical theory welcome. Fear of the reaction of ecclesiastical authorities was probably the least of the reasons why he delayed publishing his book. [ 7 ] The most important reasons for the delay was that the larger work required both astronomical observations and intricate mathematical proofs. His administrative duties certainly interfered with both the research and the writing. He was unable to make the regular observations that he needed and Frombork, which was often fogged in, was not a good place for those observations. Moreover, as Gingerich (1993, 37) pointed out,

[Copernicus] was far from the major international centers of printing that could profitably handle a book as large and technical as De revolutionibus . On the other [hand], his manuscript was still full of numerical inconsistencies, and he knew very well that he had not taken complete advantage of the opportunities that the heliocentric viewpoint offered…Furthermore, Copernicus was far from academic centers, thereby lacking the stimulation of technically trained colleagues with whom he could discuss his work.

The manuscript of On the Revolutions was basically complete when Rheticus came to visit him in 1539. The work comprised six books. The first book, the best known, discussed what came to be known as the Copernican theory and what is Copernicus's most important contribution to astronomy, the heliocentric universe (although in Copernicus's model, the sun is not truly in the center). Book 1 set out the order of the heavenly bodies about the sun: “[The sphere of the fixed stars] is followed by the first of the planets, Saturn, which completes its circuit in 30 years. After Saturn, Jupiter accomplishes its revolution in 12 years. The Mars revolves in 2 years. The annual revolution takes the series' fourth place, which contains the earth…together with the lunar sphere as an epicycle. In the fifth place Venus returns in 9 months. Lastly, the sixth place is held by Mercury, which revolves in a period of 80 days” ( Revolutions , 21-22). This established a relationship between the order of the planets and their periods, and it made a unified system. This may be the most important argument in favor of the heliocentric model as Copernicus described it. [ 8 ] It was far superior to Ptolemy's model, which had the planets revolving around the earth so that the sun, Mercury, and Venus all had the same annual revolution. In book 1 Copernicus also insisted that the movements of all bodies must be circular and uniform, and noted that the reason they may appear nonuniform to us is “either that their circles have poles different [from the earth's] or that the earth is not at the center of the circles on which they revolve” ( Revolutions , 11). Particularly notable for Copernicus was that in Ptolemy's model the sun, the moon, and the five planets seemed ironically to have different motions from the other heavenly bodies and it made more sense for the small earth to move than the immense heavens. But the fact that Copernicus turned the earth into a planet did not cause him to reject Aristotelian physics, for he maintained that “land and water together press upon a single center of gravity; that the earth has no other center of magnitude; that, since earth is heavier, its gaps are filled with water…” ( Revolutions , 10). As Aristotle had asserted, the earth was the center toward which the physical elements gravitate. This was a problem for Copernicus's model, because if the earth was no longer the center, why should elements gravitate toward it?

The second book of On the Revolutions elaborated the concepts in the first book; book 3 dealt with the procession of the equinoxes and solar theory; book 4 dealt with the moon's motions; book 5 dealt with the planetary longitude and book 6 with latitude. [ 9 ] Copernicus depended very much on Ptolemy's observations, and there was little new in his mathematics. He was most successful in his work on planetary longitude, which, as Swerdlow and Neugebauer (77) commented, was “Copernicus's most admirable, and most demanding, accomplishment…It was above all the decision to derive new elements for the planets that delayed for nearly half a lifetime Copernicus's continuation of his work — nearly twenty years devoted to observation and then several more to the most tedious kind of computation — and the result was recognized by his contemporaries as the equal of Ptolemy's accomplishment, which was surely the highest praise for an astronomer.” Surprisingly, given that the elimination of the equant was so important in the Commentariolus , Copernicus did not mention it in book 1, but he sought to replace it with an epicyclet throughout On the Revolutions . Nevertheless, he did write in book 5 when describing the motion of Mercury:

…the ancients allowed the epicycle to move uniformly only around the equant's center. This procedure was in gross conflict with the true center [of the epicycle's motion], its relative [distances], and the prior centers of both [other circles]…However, in order that this last planet too may be rescued from the affronts and pretenses of its detractors, and that its uniform motion, no less than that of the other aforementioned planets, may be revealed in relation to the earth's motion, I shall attribute to it too, [as the circle mounted] on its eccentric, an eccentric instead of the epicycle accepted in antiquity ( Revolutions , 278-79).

Although Copernicus received encouragement to publish his book from his close friend, the bishop of Chelmo Tiedemann Giese (1480-1550), and from the cardinal of Capua Nicholas Schönberg (1472-1537), it was the arrival of Georg Joachim Rheticus in Frombork that solved his needs for a supportive and stimulating colleague in mathematics and astronomy and for access to an appropriate printer. Rheticus was a professor of mathematics at the University of Wittenberg, a major center for the student of mathematics as well as for Lutheran theology. In 1538 Rheticus took a leave of absence to visit several famous scholars in the fields of astronomy and mathematics. It is not known how Rheticus learned about Copernicus's theory; he may have been convinced to visit Copernicus by one of the earlier scholars he had visited, Johann Schöner, though, as Swerdlow and Neugebauer (16) noted, by “the early 1530's knowledge of Copernicus's new theory was circulating in Europe, even reaching the high and learned circles of the Vatican.” Rheticus brought with him some mathematical and astronomical volumes, which both provided Copernicus with some important material and showed him the quality of the mathematical printing available in the German centers of publishing. [ 10 ] Rheticus's present of the 1533 edition of Regiomontanus's On all Kinds of Triangles ( De triangulis omnimodis ), for example, convinced Copernicus to revise his section on trigonometry. But Rheticus was particularly interested in showing Copernicus the work of the Nuremberg publisher Johann Petreius as a possible publisher of Copernicus's volume. Swerdlow and Neugebauer (25) plausibly suggested that “Petreius was offering to publish Copernicus's work, if not advertising by this notice that he was already committed to do so.” Rheticus wrote the Narratio prima in 1540, an introduction to the theories of Copernicus, which was published and circulated. This further encouraged Copernicus to publish his Revolutions , which he had been working on since he published the Commentariolus .

The Narratio prima was written in 1539 and took the form of a letter to Johann Schöner announcing Copernicus's findings and describing the contents of the Revolutions . He dealt with such topics as the motions of the fixed stars, the tropical year, the obliquity of the ecliptic, the problems resulting from the motion of the sun, the motions of the earth and the other planets, librations, longitude in the other five planets, and the apparent deviation of the planets from the ecliptic. He asserted that the heliocentric universe should have been adopted because it better accounted for such phenomena as the precession of the equinoxes and the change in the obliquity of the ecliptic; it resulted in a diminution of the eccentricity of the sun; the sun was the center of the deferents of the planets; it allowed the circles in the universe to revolve uniformly and regularly; it satisfied appearances more readily with fewer explanations necessary; it united all the spheres into one system. Rheticus added astrological predictions and number mysticism, which were absent from Copernicus's work.

The Narratio prima was printed in 1540 in Gdansk (then Danzig); thus, it was the first printed description of the Copernican thesis. Rheticus sent a copy to Achilles Pirmin Gasser of Feldkirch, his hometown in modern-day Austria, and Gasser wrote a foreword that was published with a second edition that was produced in 1541 in Basel. It was published again in 1596 as an appendix to the first edition of Johannes Kepler's Mysterium cosmographicum (Secret of the Universe), the first completely Copernican work by an adherent.

The publication of Rheticus's Narratio prima did not create a big stir against the heliocentric thesis, and so Copernicus decided to publish On the Revolutions . He added a dedication to Pope Paul III (r. 1534-1549), probably for political reasons, in which he expressed his hesitancy about publishing the work and the reasons he finally decided to publish it. He gave credit to Schönberg and Giese for encouraging him to publish and omitted mention of Rheticus, but it would have been insulting to the pope during the tense period of the Reformation to give credit to a Protestant minister. [ 11 ] He dismissed critics who might have claimed that it was against the Bible by giving the example of the fourth-century Christian apologist Lactantius, who had rejected the spherical shape of the earth, and by asserting, “Astronomy is written for astronomers” ( Revolutions , 5). In other words, theologians should not meddle with it. He pointed to the difficulty of calendar reform because the motions of the heavenly bodies were inadequately known. And he called attention to the fact that “if the motions of the other planets are correlated with the orbiting of the earth, and are computed for the revolution of each planet, not only do their phenomena follow therefrom but also the order and size of all the planets and spheres, and heaven itself is so linked together that in no portion of it can anything be shifted without disrupting the remaining parts and the universe as a whole” ( Revolutions , 5).

Rheticus returned to Wittenberg in 1541 and the following year received another leave of absence, at which time he took the manuscript of the Revolutions to Petreius for publishing in Nuremberg. Rheticus oversaw the printing of most of the text. However, Rheticus was forced to leave Nuremberg later that year because he was appointed professor of mathematics at the University of Leipzig. He left the rest of the management of printing the Revolutions to Andrew Osiander (1498-1552), a Lutheran minister who was also interested in mathematics and astronomy. Though he saw the project through, Osiander appended an anonymous preface to the work. In it he claimed that Copernicus was offering a hypothesis, not a true account of the working of the heavens: “Since he [the astronomer] cannot in any way attain to the true causes, he will adopt whatever suppositions enable the motions to be computed correctly from the principles of geometry for the future as well as for the past …these hypotheses need not be true nor even probable” ( Revolutions, xvi ). This clearly contradicted the body of the work. Both Rheticus and Giese protested, and Rheticus crossed it out in his copy.

Copernicus's fame and book made its way across Europe over the next fifty years, and a second edition was brought out in 1566. [ 12 ] As Gingerich's census of the extant copies showed, the book was read and commented on by astronomers. Gingerich (2004, 55) noted “the majority of sixteenth-century astronomers thought eliminating the equant was Copernicus' big achievement.”

While Martin Luther may have made negative comments about Copernicus because the idea of the heliocentric universe seemed to contradict the Bible, [ 13 ] Philip Melanchthon (1497-1560), who presided over the curriculum at the University of Wittenberg, eventually accepted the importance of teaching Copernicus's ideas, perhaps because Osiander's preface made the work more palatable. His son-in-law Caspar Peucer (1525-1602) taught astronomy there and began teaching Copernicus's work. As a result, the University of Wittenberg became a center where Copernicus's work was studied. But Rheticus was the only Wittenberg scholar who accepted the heliocentric idea. Robert Westman (1975a, 166-67) suggested that there was a ‘Wittenberg Interpretation’: astronomers appreciated and adopted some of Copernicus's mathematical models but rejected his cosmology, and some were pleased with his replacement of the equant by epicyclets. One of these was Erasmus Reinhold (1511-1553), a leading astronomer at Wittenberg who became dean and rector. He produced a new set of planetary tables from Copernicus's work, the Prutenic Tables. Although, as Gingerich (1993, 232) pointed out, “there was relatively little to distinguish between the accuracy of the Alfonsine Tables and the Prutenic Tables ,” the latter were more widely adopted; Gingerich plausibly suggested that the fact that the Prutenic Tables more accurately predicted a conjunction between Jupiter and Saturn in 1563 made the difference. Reinhold did not accept the heliocentric theory, but he admired the elimination of the equant. The Prutenic Tables excited interest in Copernicus's work.

Tycho Brahe (1546-1601) was the greatest astronomical observer before the invention of the telescope. He called Copernicus a ‘second Ptolemy’ (quoted in Westman 1975, 307) and appreciated both the elimination of the equant and the creation of a planetary system. But Tycho could not adopt the Copernican system, partly for the religious reason that it went against what the Bible seemed to preach. He, therefore, adopted a compromise, the ‘geoheliostatic’ system in which the two inner planets revolved around the sun and that system along with the rest of the planets revolved around the earth.

Among Catholics, Christoph Clavius (1537-1612) was the leading astronomer in the sixteenth century. A Jesuit himself, he incorporated astronomy into the Jesuit curriculum and was the principal scholar behind the creation of the Gregorian calendar. Like the Wittenberg astronomers, Clavius adopted Copernican mathematical models when he felt them superior, but he believed that Ptolemy's cosmology — both his ordering of the planets and his use of the equant — was correct.

Pope Clement VII (r. 1523-1534) had reacted favorably to a talk about Copernicus's theories, rewarding the speaker with a rare manuscript. There is no indication of how Pope Paul III, to whom On the Revolutions was dedicated reacted; however, a trusted advisor, Bartolomeo Spina of Pisa (1474-1546) intended to condemn it but fell ill and died before his plan was carried out. Thus, in 1600 there was no official Catholic position on the Copernican system, and it was certainly not a heresy. When Giordano Bruno (1548-1600) was burned at the stake as a heretic, it had nothing to do with his writings in support of Copernican cosmology.

Michael Maestlin (1550-1631) of the University of Tübingen was the earliest astronomer after Rheticus to adopt Copernicus's heliocentricism. Although he wrote a popular textbook that was geocentric, he taught his students that the heliocentric system was superior. He also rejected Osiander's preface. Maestlin's pupil Johannes Kepler wrote the first book that was openly heliocentric in its orientation, the Mysterium cosmographicum (Secret of the Universe). And, of course, Kepler eventually built on Copernicus's work to create a much more accurate description of the solar system.

A. Complete Works of Copernicus

In 1972 the Polish Academy of Sciences under the direction of J. Dobrzycki published critical editions of the Complete Works of Copernicus in six languages: Latin, English, French, German, Polish, and Russian. The first volume was a facsimile edition. The annotations in the English translations are more comprehensive than the others. The English edition was reissued as follows:

• Minor Works , 1992, trans. E. Rosen, Baltimore: The Johns Hopkins University Press (originally published as volume 3 of Nicholas Copernicus: Complete Works , Warsaw: Polish Scientific Publishers, 1985). Referred to herein as MW .
• On the Revolutions , 1992, trans. E. Rosen, Baltimore: The Johns Hopkins University Press (originally published as volume 2 of Nicholas Copernicus: Complete Works , Warsaw: Polish Scientific Publishers, 1978). Referred to herein as Revolutions .

B. Other Translations of Copernicus's Works

• On the Revolutions of the Heavenly Spheres , 1955, trans. C.G. Wallis, vol. 16 of Great Books of the Western World . Chicago: Encyclopedia Britannica; 1995, reprint, Amherst: Prometheus Books
• On the Revolutions of the Heavenly Spheres , 1976, trans. and ed. A.M. Duncan, Newton Abbot: David & Charles
• “The Derivation and First Draft of Copernicus's Planetary Theory: A Translation of the Commentariolus with Commentary,” 1973, trans. N.M. Swerdlow, Proceedings of the American Philosophical Society 117: 423-512

C. Translations of Other Primary Sources

• Bruno, G., 1977, The Ash Wednesday Supper , trans. E.A. Gosselin and L.S. Lerner, Hamden: Archon Books; 1995, reprint, Toronto: University of Toronto Press
• Rheticus, G.J., Narratio prima , in E. Rosen, 1971, 107-96

D. Secondary Sources

• Cohen, I.B., 1960, The Birth of a New Physics , Garden City: Anchor Books; 1985, rev. ed., New York: W.W. Norton
• -----. 1985, Revolutions in Science , Cambridge, MA: Harvard University Press
• Crowe, M.J., 1990, Theories of the World from Antiquity to the Copernican Revolution , New York: Dover Publications
• Gillespie, C.C. (ed.), 1970-80, Dictionary of Scientific Biography , New York: Scribner's
• Gingerich, O., 1993, The Eye of Heaven: Ptolemy, Copernicus, Kepler , New York: American Institute of Physics
• -----. 2002, An Annotated Census of Copernicus' De revolutionibus, (Nuremberg, 1543 and Basel, 1566), Leiden: Brill Academic Publishers
• -----. 2004, The Book Nobody Read: Chasing the Revolutions of Nicolaus Copernicus , New York: Walker & Company
• Grendler, P., 2002, The Universities of the Italian Renaissance , Baltimore: The Johns Hopkins University Press
• Hallyn, F., 1990, The Poetic Structure of the World: Copernicus and Kepler , trans. D. Leslie, New York: Zone Books
• Koestler, A., 1989, The Sleepwalkers , London: Penguin, reprint of 1959 edition
• Koyré, A., 1957, From the Closed World to the Infinite Universe , Baltimore: The Johns Hopkins University Press
• -----. 1973, The Astronomical Revolution: Copernicus, Kepler, Borelli , trans. R.E.W. Maddison, Ithaca: Cornell University Press
• Kuhn, T., 1957, The Copernican Revolution , Cambridge, MA: Harvard University Press
• Rosen, E.,1970a, “Copernicus,” in Gillespie (ed.), 3:401-11
• -----. 1970b, “Rheticus,” Gillespie (ed.), 11:395-97
• -----. 1971, Three Copernican Treatises , 3d ed., New York: Octagon Books
• -----. 1975, “Was Copernicus' Revolutions Approved by the Pope?” Journal of the History of Ideas , 36:531-42
• -----. 1984, Copernicus and the Scientific Revolution , Malabar, FL: Krieger Publishing Co.
• Shumaker, W., 1979, The Occult Sciences in the Renaissance: A Study in Intellectual Patterns , Berkeley: University of California Press, reprint of 1972 edition
• Siraisi, N., 1981, Taddeo Alderotti and His Pupils: Two Generations of Italian Medical Learning , Princeton: Princeton University Press
• -----. 1990, Medieval and Early Renaissance Medicine : An Introduction to Knowledge and Practice , Chicago: University of Chicago Press
• Swerdlow, N., 2000, “Copernicus, Nicolaus (1473-1543),” in Encyclopedia of the Scientific Revolution , W. Applebaum (ed.), 162-68, New York: Garland Publishing
• Swerdlow, N. and O. Neugebauer, 1984, Mathematical Astronomy in Copernicus's De Revolutionibus , 2 vols., New York: Springer-Verlag
• Westman, R., 1975a, “The Melanchthon Circle, Rheticus, and the Wittenberg Interpretation of the Copernican Theory,” Isis :165-93
• -----. 1975b, “Three Responses to the Copernican Theory: Johannes Praetorius, Tycho Brahe, and Michael Maestlin,” in Westman (ed.), 1975c
• -----. (ed), 1975c, The Copernican Achievement , Berkeley: University of California Press
• -----. 1993, “Copernicus and the Prognosticators: The Bologna Period, 1496-1500,” Universitas No. 5 (December 1993): 1-5
• Yates, F., 1979, Giordano Bruno and the Hermetic Tradition , Chicago: University of Chicago Press, reprint of 1964 edition
• Nicolaus Copernicus , in the MacTutor History of Mathematics Archive , maintained by J.J. O'Connor and E.F. Robertson (School of Mathematics and Statistics University of St. Andrews, Scotland)

Aristotle | -->Bruno, Giordano --> | Galileo Galilei | -->Kepler, Johannes --> | Kuhn, Thomas

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

• View all journals
• Explore content
• About the journal
• Publish with us
• Sign up for alerts
• NEWS AND VIEWS
• 22 August 2023

From the archive: Copernicus’s legacy, and a hungry pigeon

50 years ago

Access options

Access Nature and 54 other Nature Portfolio journals

Get Nature+, our best-value online-access subscription

24,99 € / 30 days

cancel any time

Subscribe to this journal

Receive 51 print issues and online access

185,98 € per year

only 3,65 € per issue

Rent or buy this article

Prices vary by article type

Prices may be subject to local taxes which are calculated during checkout

doi: https://doi.org/10.1038/d41586-023-02355-5

Reprints and permissions

• Astronomy and astrophysics

Rapa Nui’s population history rewritten using ancient DNA

News & Views 11 SEP 24

Famed Pacific island’s population 'crash' debunked by ancient DNA

News 11 SEP 24

Back to the future: two books that tried to predict how science would evolve

News & Views 10 SEP 24

One month convection timescale on the surface of a giant evolved star

Article 11 SEP 24

Swirling star bubbles offer a glimpse of the Sun’s future

NASA okays mission to search for life on Jupiter’s moon Europa

News 10 SEP 24

Drosophila are hosts to the first described parasitoid wasp of adult flies

Bumblebees’ sense of smell can’t take the heat

Research Highlight 30 AUG 24

Lonely? Playful? Why are dolphin attacks rising in Japan?

News Q&A 28 AUG 24

PhD and MSc position at the Faculty of Biology in the Technion - Israel Institute of Technology

Join the Faculty of Biology at the Technion – Israel Institute of Technology The Technion, located in Haifa, Israel, is a world-renowned institutio...

Israel (IL)

Faculty of Biology, Technion

Call for Participation at Forum of Young Scientists Shenzhen University of Advanced Technology

Shenzhen University of Advanced Technology (SUAT) invites interested individuals to its Forum of Young Scientists.

Shenzhen, Guangdong, China

Shenzhen University of Advanced Technology

2024 Recruitment notice Shenzhen Institute of Synthetic Biology: Shenzhen, China

The wide-ranging expertise drawing from technical, engineering or science professions...

Shenzhen,China

Shenzhen Institute of Synthetic Biology

Chief Operating Officer

Salary: £425,000 per annumContract: PermanentClosing date: Sunday 22nd September Founded in 1936, Wellcome is a politically and financially independen

England, London

WellcomeTrust

Executive Director, Discovery

Salary: £400,000 per annumContract: PermanentClosing date: Sunday 22nd September Founded in 1936, Wellcome is a politically and financially independe

London, England

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

A Thought Experiment

Friday, january 01, 2010, nicholas copernicus.

0 Comments:

Post a Comment

<< Home

View my complete profile

Previous Posts

• SUPER G-FORCE
• Frequently Asked Questions (FAQs)
• 1G TABLE: Accelerate for 1 Year
• DOWN-LINK: GEO to Surface
• DYNAMIC EFFICIENCY FACTOR
• Lorentz Transform and Related Concepts
• Ref Mat'l: Review Rate and Range
• TRANSIENT: Performance Progression...Water, water...

This is a paragraph of text that could go in the sidebar.