Nicolaus Copernicus was born on 19 February 1473, in the city of Thorn (Toru?) in Royal Prussia, part of the Kingdom of Poland.

His father was a merchant from Kraków and his mother was the daughter of a wealthy Toru? merchant. Nicolaus was the youngest of four children. His brother Andreas (Andrew) became an Augustinian canon at Frombork (Frauenburg). His sister Barbara, named after her mother, became a Benedictine nun and in her final years (she died after 1517) prioress of a convent in Che?mno (Culm, Kulm). His sister Katharina married the businessman and Toru? city councilor Barthel Gertner and left five children, whom Copernicus looked after to the end of his life.

Copernicus never married or had children.

Father's family

The father’s family can be traced to a village in Silesia near Nysa (Neiße). The village's name has been variously spelled Kopernik, Köppernig, Köppernick, and today Koperniki. In the 14th century, members of the family began moving to various other Silesian cities, to the Polish capital, Kraków (Cracow, 1367), and to Toru? (1400). The father, likely the son of Jan, came from the Kraków line.

Nicolaus was named after his father, who appears in records for the first time as a well-to-do Catholic merchant who dealt in copper, selling it mostly in Danzig (Gda?sk). He moved from Kraków to Toru? around 1458. Toru?, situated on the Vistula River, was at that time embroiled in the Thirteen Years' War , in which the Kingdom of Poland and the Prussian Confederation, an alliance of Prussian cities, gentry and clergy, fought the Teutonic Order over control of the region. In this war predominantly German-culture and German speaking Hanseatic cities like Danzig (Gda?sk) and Thorn (Toru?), the hometown of Nicolaus Copernicus, chose to support the Polish king, who promised to respect the cities' traditional vast independence, which the Teutonic Order had challenged. The father of Nicolaus was actively engaged in the politics of the day, and supported Poland and the cities against the Teutonic Order. In 1454 he mediated negotiations between Poland’s Cardinal Zbigniew Ole?nicki and the Prussian cities for repayment of war loans. In the Second Peace of Thorn , the Teutonic Order formally relinquished all claims to its western provinces, which as Royal Prussia remained a region of Poland for the next 300 years.

The father married Barbara Watzenrode, the astronomer's mother, between 1461 and 1464. He died sometime between 1483 and 1485. Upon the father’s death, young Nicolaus’ maternal uncle, Lucas Watzenrode the Younger (1447—1512), took the boy under his protection and saw to his education and career.

Mother's family

Nicolaus’ mother, Barbara Watzenrode, was the daughter of Lucas Watzenrode the Elder and his wife Katherine (née Modlibóg). Not much is known about her life, but she is believed to have died when Nicolaus was a small boy. The Watzenrodes, who were Roman Catholic, had come from the ?widnica (Schweidnitz) region of Silesia and had settled in Toru? after 1360, becoming prominent members of the city’s patrician class. Through the Watzenrodes' extensive family relationships by marriage, they were related to wealthy families of Toru?, Danzig and Elbl?g (Elbing), and to the prominent Czapski, Dzia?y?ski, Konopacki and Ko?cielecki noble families. The Modlibógs (literally, in Polish, "Pray to God") were a prominent Roman Catholic Polish family who had been well known in Poland's history since 1271. Lucas and Katherine had three children: Lucas Watzenrode the Younger, who would become Copernicus' patron; Barbara, the astronomer's mother; and Christina, who in 1459 married the merchant and mayor of Toru?, Tiedeman von Allen.

Lucas Watzenrode the Elder was well-regarded in Toru? as a devout man and honest merchant, and he was active politically. He was a decided opponent of the Teutonic Knights and an ally of Polish King Casimir IV Jagiellon. In 1453 he was the delegate from Toru? at the Grudzi?dz (Graudenz) conference that planned to ally the cities of the Prussian Confederation with Casimir IV in their subsequent war against the Teutonic Knights. During the Thirteen Years' War that ensued the following year, he actively supported the war effort with substantial monetary subsidies, with political activity in Toru? and Danzig, and by personally fighting in battles at ?asin (Lessen) and Marienburg (Malbork). He died in 1462.

Lucas Watzenrode the Younger, the astronomer's maternal uncle and patron, was educated at the University of Krakow (now Jagiellonian University) and at the universities of Cologne and Bologna. He was a bitter opponent of the Teutonic Order and its Grand Master, who once referred to Watzenrode as “the devil incarnate.” In 1489 Watzenrode was elected Bishop of Warmia (Ermeland, Ermland) against the preference of King Casimir IV, who had hoped to install his own son in that seat. As a result, Watzenrode quarreled with the king until Casimir IV’s death three years later. Watzenrode was then able to form close relations with three successive Polish monarchs: John I Albert, Alexander Jagiellon, and Sigismund I the Old. He was a friend and key advisor to each ruler, and his influence greatly strengthened the ties between Warmia and Poland proper. Watzenrode came to be considered the most powerful man in Warmia, and his wealth, connections and influence allowed him to secure Copernicus’ education and career as a canon at Frombork (Frauenberg) Cathedral.

Languages

Copernicus is postulated to have spoken Latin, German, and Polish with equal fluency. He also spoke Greek and Italian. The vast majority of Copernicus’ surviving works are in Latin, which in his lifetime was the language of academia in Europe. Latin was also the official language of the Roman Catholic Church and of Poland's royal court, and thus all of Copernicus’ correspondence with the Church and with Polish leaders was in Latin.

There survives a German-language correspondence between Copernicus and Duke Albert of Prussia. Some scholars hold that German should be considered Copernicus’ native language because Thorn/Toru? was then predominantly German-speaking, because a German-language correspondence survives to illustrate Copernicus' proficiency in that language, and because, while studying law at Bologna in 1496, he signed into the German natio (Natio Germanorum)...a student organization which, according to its 1497 by-laws, was open to German-speaking students of all kingdoms and states.

On the other hand, Renaissance Poles wrote variously in Latin, in Polish or in both languages.

Name

In Copernicus’ day, people were often called after the places where they lived. Like the Silesian village that inspired it, Copernicus’ surname has been spelled variously. Today the English-speaking world knows the astronomer principally by the Latinized name, "Nicolaus Copernicus."

The surname likely had something to do with the local Silesian copper-mining industry,though some scholars assert that it may have been inspired by the dill plant (in Polish, "koperek" or "kopernik") that grows wild in Silesia.

As was to be the case with William Shakespeare a century later, numerous spelling variants of the name are documented for the astronomer and his relatives. The name first appeared as a place name in Silesia in the 13th century, where it was spelled variously in Latin documents. Copernicus "was rather indifferent about orthography." During his childhood, the name of his father (and thus of the future astronomer) was recorded in Toru? as Niclas Koppernigk around 1480. At Kraków he signed his name "Nicolaus Nicolai de Torunia." At Bologna in 1496, he registered in the Matricula Nobilissimi Germanorum Collegii resp. Annales Clarissimae Nacionis Germanorum of the Natio Germanica Bononiae as Dominus Nicolaus Kopperlingk de Thorn — IX grosseti. At Padua, Copernicus signed his name "Nicolaus Copernik", later as "Coppernicus." He signed a self-portrait, a copy of which is now at Jagiellonian University, "N Copernic." The astronomer Latinized his name to Coppernicus, generally with two "p"s (in 23 of 31 documents studied), but later in life he used a single "p". On the title page of De revolutionibus, Rheticus published the name as (in the genitive, or possessive, case) "Nicolai Copernici".

Education

Copernicus' uncle Watzenrode maintained contacts with the leading intellectual figures in Poland and was a friend of the influential Italian-born humanist and Kraków courtier, Filippo Buonaccorsi. Watzenrode seems first to have sent young Copernicus to the St. John's School at Toru? where he himself had been a master. Later, according to Armitage (some scholars differ), the boy attended the Cathedral School at W?oc?awek, up the Vistula River from Toru?, which prepared pupils for entrance to the University of Krakow, Watzenrode's alma mater in Poland's capital.

In the winter semester of 1491—92 Copernicus, as "Nicolaus Nicolai de Thuronia," matriculated together with his brother Andrew at the University of Krakow (now Jagiellonian University). Copernicus began his studies in the Department of Arts (from the fall of 1491, presumably until the summer or fall of 1495) in the heyday of the Kraków astronomical-mathematical school, acquiring the foundations for his subsequent mathematical achievements. According to a later but credible tradition (Jan Bro?ek), Copernicus was a pupil of Albert Brudzewski, who by then (from 1491) was a professor of Aristotelian philosophy but taught astronomy privately outside the university; Copernicus became familiar with Bro?ek's widely read commentary to Georg von Peuerbach's Theoricæ novæ planetarum and almost certainly attended the lectures of Bernard of Biskupie and Wojciech Krypa of Szamotu?y and probably other astronomical lectures by Jan of G?ogów, Michael of Wroc?aw, Wojciech of Pniewy and Marcin Bylica of Olkusz.

Copernicus' Kraków studies gave him a thorough grounding in the mathematical-astronomical knowledge taught at the university (arithmetic, geometry, geometric optics, cosmography, theoretical and computational astronomy), a good knowledge of the philosophical and natural-science writings of Aristotle (De coelo, Metaphysics) and Averroes (which later would play an important role in shaping his theory), stimulated his interest in learning, and made him conversant with humanistic culture. Copernicus broadened the knowledge that he took from the university lecture halls with independent reading of books that he acquired during his Kraków years (Euclid, Haly Abenragel, the Alfonsine Tables, Johannes Regiomontanus' Tabulae directionum); to this period, probably, also date his earliest scientific notes, now preserved partly at Uppsala University. At Kraków Copernicus began collecting a large library on astronomy; it would later be carried off as war booty by the Swedes during the Deluge and is now at the Uppsala University Library.

Copernicus' four years at Kraków played an important role in the development of his critical faculties and initiated his analysis of the logical contradictions in the two "official" systems of astronomy...Aristotle's theory of homocentric spheres, and Ptolemy's mechanism of eccentric and epicycles--the surmounting and discarding of which constituted the first step toward the creation of Copernicus' own doctrine of the structure of the universe.

Without taking a degree, probably in the fall of 1495, Copernicus left Kraków for the court of his uncle Watzenrode, who in 1489 had been elevated to Prince-Bishop of Warmia and soon (after November 1495) sought to place his nephew in a Warmia canonry vacated by the 26 August 1495 death of its previous tenant. For unclear reasons...probably due to opposition from part of the chapter, who appealed to Rome--Copernicus' installation was delayed, inclining Watzenrode to send both his nephews to study law in Italy, seemingly with a view to furthering their ecclesiastic careers and thereby also strengthening his own influence in the Warmia chapter.

Leaving Warmia in mid-1496...possibly with the retinue of the chapter's chancellor, Jerzy Pranghe, who was going to Italy...in the fall (October?) of that year Copernicus arrived in Bologna and a few months later (after 6 January 1497) signed himself into the register of the Bologna University of Jurists' "German nation," which also included Polish youths from Silesia, Prussia and Pomerania as well as students of other nationalities.

It was only on 20 October 1497 that Copernicus, by proxy, formally succeeded to the Warmia canonry, which had been granted to him two years earlier. To this, by a document dated 10 January 1503 at Padua, he would add a sinecure at the Collegiate Church of the Holy Cross in Wroc?aw (Breslau), Silesia, Bohemia. Despite having received a papal indult on 29 November 1508 to receive further benefices, through his ecclesiastic career Copernicus not only did not acquire further prebends and higher stations (prelacies) at the chapter, but in 1538 he relinquished the Wroc?aw sinecure. It is uncertain whether he was ordained a priest; he may only have taken minor orders, which sufficed for assuming a chapter canonry.

of [Copernicus'] birth by the City, the University, the Academy of Sciences of the Institute of Bologna, the Polish Academy of Sciences. 1473 [...] 1973."]]

During his three-year stay at Bologna, between fall 1496 and spring 1501, Copernicus seems to have devoted himself less keenly to studying canon law (he received his doctorate in law only after seven years, following a second return to Italy in 1503) than to studying the humanities--probably attending lectures by Filippo Beroaldo, Antonio Urceo, called Codro, Giovanni Garzoni and Alessandro Achillini--and to studying astronomy. He met the famous astronomer Domenico Maria Novara da Ferrara and became his disciple and assistant. Copernicus was developing new ideas inspired by reading the "Epitome of the Almagest" (Epitome in Almagestum Ptolemei) by George von Peuerbach and Johannes Regiomontanus (Venice, 1496). He verified its observations about certain peculiarities in Ptolemy's theory of the Moon's motion, by conducting on 9 March 1497 at Bologna a memorable observation of Aldebaran, the brightest star in the Taurus constellation, whose results reinforced his doubts as to the geocentric system. Copernicus the humanist sought confirmation for his growing doubts through close reading of Greek and Latin authors (Pythagoras, Aristarchos of Samos, Cleomedes, Cicero, Pliny the Elder, Plutarch, Philolaus, Heraclides, Ecphantos, Plato), gathering, especially while at Padua, fragmentary historic information about ancient astronomical, cosmological and calendar systems.

Copernicus spent the jubilee year 1500 in Rome, where he arrived with his brother Andrew that spring, doubtless to perform an apprenticeship at the Papal Curia. Here, too, however, he continued his astronomical work begun at Bologna, observing, for example, a lunar eclipse on the night of 5—6 November 1500. According to a later account by Rheticus, Copernicus also...probably privately, rather than at the Roman Sapienza--as a "Professor Mathematum" (professor of astronomy) delivered, "to numerous... students and... leading masters of the science," public lectures devoted probably to a critique of the mathematical solutions of contemporary astronomy.

On his return journey doubtless stopping briefly at Bologna, in mid-1501 Copernicus arrived back in Warmia. After on 28 July receiving from the chapter a two-year extension of leave in order to study medicine (since "he may in future be a useful medical advisor to our Reverend Superior [Bishop Lucas Watzenrode] and the gentlemen of the chapter"), in late summer or in the fall he returned again to Italy, probably accompanied by his brother Andrew and by Canon B. Sculteti. This time he studied at the University of Padua, famous as a seat of medical learning, and...except for a brief visit to Ferrara in May-June 1503 to pass examinations for, and receive, his doctorate in canon law...he remained at Padua from fall 1501 to summer 1503.

Copernicus studied medicine probably under the direction of leading Padua professors...Bartolomeo da Montagnana, Girolamo Fracastoro, Gabriele Zerbi, Alessandro Benedetti...and read medical treatises that he acquired at this time, by Valescus de Taranta, Jan Mesue, Hugo Senensis, Jan Ketham, Arnold de Villa Nova, and Michele Savonarola, which would form the embryo of his later medical library.

One of the subjects that Copernicus must have studied wasastrology, since it was considered an important part of a medicaleducation. However, unlike mostother prominent Renaissance astronomers, he appears never to havepracticed or expressed any interest in astrology.

As at Bologna, Copernicus did not limit himself to his official studies. It was probably the Padua years that saw the beginning of his Hellenistic interests. He familiarized himself with Greek language and culture with the aid of Theodorus Gaza's grammar (1495) and J.B. Chrestonius' dictionary (1499), expanding his studies of antiquity, begun at Bologna, to the writings of Bessarion, J. Valla and others. There also seems to be evidence that it was during his Padua stay that there finally crystallized the idea of basing a new system of the world on the movement of the Earth.

As the time approached for Copernicus to return home, in spring 1503 he journeyed to Ferrara where, on 31 May 1503, having passed the obligatory examinations, he was granted the degree of doctor of canon law. No doubt it was soon after (at latest, in fall 1503) that he left Italy for good to return to Warmia.

Work

Having completed all his studies in Italy, 30-year-old Copernicus returned to Warmia, where ... apart from brief journeys to Kraków and to nearby Prussian cities (Toru?, Gda?sk, Elbl?g, Grudzi?dz, Malbork, Königsberg) ... he would live out the remaining 40 years of his life.

The Prince-Bishopric of Warmia enjoyed substantial autonomy, with its own diet (parliament), army, monetary unit (the same as in the other parts of Royal Prussia) and treasury.

From 1503 to 1510, or perhaps till his uncle's death (29 March 1512), Copernicus was his personal secretary and physician and resided in the Bishop's castle at Lidzbark Warmi?ski (Heilsberg). It is there that he began work on his heliocentric theory. In his official capacity, he took part in nearly all his uncle's political, ecclesiastic and administrative-economic duties. From the beginning of 1504, Copernicus accompanied Watzenrode to sessions of the Royal Prussian diet held at Malbork and Elbl?g and, write Dobrzycki and Hajdukiewicz, "participated... in all the more important events in the complex diplomatic game that that ambitious politician and statesman played in defense of the particular interests of Prussia and Warmia, between hostility to the [Teutonic] Order and loyalty to the [Polish] Crown."In 1504—12 Copernicus made numerous journeys as part of his uncle's retinue...in 1504, to Toru? and Gda?sk (Danzig), to a session of the Royal Prussian Council in the presence of Poland's King Alexander Jagiellon; to sessions of the Prussian diet at Malbork (1506), Elbl?g (1507) and Sztum (1512); and he may have attended a Pozna? session (1510) and the coronation of Poland's King Sigismund I the Old in Kraków (1507). Watzenrode's itinerary suggests that in spring 1509 Copernicus may have attended the Kraków sejm.

It was probably on the latter occasion, in Kraków, that Copernicus submitted for printing at Jan Haller's press his translation, from Greek to Latin, of a collection, by the 7th-century Byzantine historian Theophylact Simocatta, of 85 brief poems called Epistles, or letters, supposed to have passed between various characters in a Greek story. They are of three kinds..."moral," offering advice on how people should live; "pastoral," giving little pictures of shepherd life; and "amorous," comprising love poems. They are arranged to follow one another in a regular rotation of subjects. Copernicus had translated the Greek verses into Latin prose, and he now published his version as Theophilacti scolastici Simocati epistolae morales, rurales et amatoriae interpretatione latina, which he dedicated to his uncle in gratitude for all the benefits he had received from him. With this translation, Copernicus declared himself on the side of the humanist in the struggle over the question whether Greek literature should be revived. Copernicus' first poetic work was a Greek epigram, composed probably during a visit to Kraków, for Johannes Dantiscus' epithalamium for Barbara Zapolya's 1512 wedding to King Zygmunt I the Old.

Some time before 1514, Copernicus wrote an initial outline of his heliocentric theory known only from later transcripts, by the title (perhaps given to it by a copyist), Nicolai Copernici de hypothesibus motuum coelestium a se constitutis commentariolus...commonly referred to as the Commentariolus. It was a succinct theoretical description of the world's heliocentric mechanism, without mathematical apparatus, and differed in some important details of geometric construction from De revolutionibus; but it was already based on the same assumptions regarding Earth's triple motions. The Commentariolus, which Copernicus consciously saw as merely a first sketch for his planned book, was not intended for printed distribution. He made only a very few manuscript copies available to his closest acquaintances, including, it seems, several Kraków astronomers with whom he collaborated in 1515—30 in observing eclipses. Tycho Brahe would include a fragment from the Commentariolus in his own treatise, Astronomiae instauratae progymnasmata, published in Prague in 1602, based on a manuscript that he had received from the Bohemian physician and astronomer Tadeá? Hájek, a friend of Rheticus. The Commentariolus would appear complete in print for the first time only in 1878.In 1510 or 1512 Copernicus moved to Frombork, a town to the northwest at the Vistula Lagoon on the Baltic Sea coast. There, in April 1512, he participated in the election of Fabian of Lossainen as Prince-Bishop of Warmia. It was only in early June 1512 that the chapter gave Copernicus an "external curia"...a house outside the defensive walls of the cathedral mount. In 1514 he purchased the northwestern tower within the walls of the Frombork stronghold. He would maintain both these residences to the end of his life, despite the devastation of the chapter's buildings by a raid against Frombork carried out by the Teutonic Order in January 1520, during which Copernicus' astronomical instruments were probably destroyed. Copernicus conducted astronomical observations in 1513—16 presumably from his external curia; and in 1522—43, from an unidentified "small tower" (turricula), using primitive instruments modeled on ancient ones...the quadrant, triquetrum, armillary sphere. At Frombork Copernicus conducted over half of his more than 60 registered astronomical observations.

Having settled permanently at Frombork, where he would reside to the end of his life, with interruptions in 1516-19 and 1520—21, Copernicus found himself at the Warmia chapter's economic and administrative center, which was also one of Warmia's two chief centers of political life. In the difficult, politically complex situation of Warmia, threatened externally by the Teutonic Order's aggressions (attacks by Teutonic bands; the Polish-Teutonic War of 1519-21; Albrecht's plans to annex Warmia), internally subject to strong separatist pressures (the selection of the prince-bishops of Warmia; currency reform), he, together with part of the chapter, represented a program of strict cooperation with the Polish Crown and demonstrated in all his public activities (the defense of his country against the Order's plans of conquest; proposals to unify its monetary system with the Polish Crown's; support for Poland's interests in the Warmia dominion's ecclesiastic administration) that he was consciously a citizen of the Polish-Lithuanian Republic. Soon after the death of uncle Bishop Watzenrode, he participated in the signing of the Second Treaty of Piotrków Trybunalski (7 December 1512), governing the appointment of the Bishop of Warmia, declaring, despite opposition from part of the chapter, for loyal cooperation with the Polish Crown.

That same year (before 8 November 1512) Copernicus assumed responsibility, as magister pistoriae, for administering the chapter's economic enterprises (he would hold this office again in 1530), having already since 1511 fulfilled the duties of chancellor and visitor of the chapter's estates.

His administrative and economic dutes did not distract Copernicus, in 1512-15, from intensive observational activity. The results of his observations of Mars and Saturn in this period, and especially a series of four observations of the Sun made in 1515, led to discovery of the variability of Earth's eccentric and of the movement of the solar apogee in relation to the fixed stars, which in 1515-19 prompted his first revisions of certain assumptions of his system. Some of the observations that he made in this period may have had a connection with a proposed reform of the Julian calendar made in the first half of 1513 at the request of the Bishop of Fossombrone, Paul of Middelburg. Their contacts in this matter in the period of the Fifth Lateran Council were later memorialized in a complimentary mention in Copernicus' dedicatory epistle in De revolutionibus orbium coelestium and in a treatise by Paul of Middelburg, Secundum compendium correctionis Calendarii (1516), which mentions Copernicus among the learned men who had sent the Council proposals for the calendar's emendation.

During 1516—21, Copernicus resided at Olsztyn Castle as economic administrator of Warmia, including Olsztyn (Allenstein) and Pieni??no (Mehlsack). While there, he wrote a manuscript, Locationes mansorum desertorum (Locations of Deserted Fiefs), with a view to populating those fiefs with industrious farmers and so bolstering the economy of Warmia. When Olsztyn was besieged by the Teutonic Knights during the Polish—Teutonic War , Copernicus directed the defense of Olsztyn and Warmia by Royal Polish forces. He also represented the Polish side in the ensuing peace negotiations.

Copernicus worked for years with the Royal Prussian diet, and with Duke Albert of Prussia (against whom Copernicus had defended Warmia in the Polish-Teutonic War), and advised King Sigismund, on monetary reform. He participated in discussions in the East Prussian diet about coinage reform in the Prussian countries; a question that concerned the diet was who had the right to mint coin. Political developments in Prussia culminated in the 1525 establishment of the Duchy of Prussia as a Protestant state in vassalage to Poland.

In 1526 Copernicus wrote a study on the value of money, Monetae cudendae ratio. In it he formulated an early iteration of the theory, now called Gresham's Law, that "bad" (debased) coinage drives "good" (un-debased) coinage out of circulation...70 years before Thomas Gresham. He also formulated a version of quantity theory of money. Copernicus' recommendations on monetary reform were widely read by leaders of both Prussia and Poland in their attempts to stabilize currency.

In 1533, Johann Widmanstetter, secretary to Pope Clement VII, explained Copernicus' heliocentric system to the Pope and two cardinals. The Pope was so pleased that he gave Widmanstetter a valuable gift.

In 1535 Bernard Wapowski wrote a letter to a gentleman in Vienna, urging him to publish an enclosed almanac, which he claimed had been written by Copernicus. This is the first and only mention of a Copernicus almanac in the historical records. The "almanac" was likely Copernicus' tables of planetary positions. Wapowski's letter mentions Copernicus' theory about the motions of the earth. Nothing came of Wapowski's request, because he died a couple of weeks later.

Following the death of Prince-Bishop of Warmia Mauritius Ferber (1 July 1537), Copernicus participated in the election of his successor, Johannes Dantiscus (20 September 1537). Copernicus was one of four candidates for the post, written in at the initiative of Tiedemann Giese; but his candidacy was actually pro forma, since Dantiscus had earlier been named coadjutor bishop to Ferber.

At first Copernicus maintained friendly relations with the new Prince-Bishop, assisting him medically in spring 1538 and accompanying him that summer on an inspection tour of Chapter holdings. But that autumn, their friendship was strained by suspicions over Copernicus' housekeeper, Anna Schilling, whom Dantiscus removed from Frombork in 1539.In his younger days, Copernicus the physician had treated his uncle, brother and other chapter members. In later years he was called upon to attend the elderly bishops who in turn occupied the see of Warmia...Mauritius Ferber and Johannes Dantiscus...and, in 1539, his old friend Tiedemann Giese, Bishop of Che?mno (Kulm). In treating such important patients, he sometimes sought consultations from other physicians, including the physician to Duke Albert and, by letter, the Polish Royal Physician.

In the spring of 1541, Duke Albert summoned Copernicus to Königsberg to attend the Duke's counselor, George von Kunheim, who had fallen seriously ill, and for whom the Prussian doctors seemed unable to do anything. Copernicus went willingly; he had met von Kunheim during negotiations over reform of the coinage. And Copernicus had come to feel that Albert himself was not such a bad person; the two had many intellectual interests in common. The Chapter readily gave Copernicus permission to go, as it wished to remain on good terms with the Duke, despite his Lutheran faith. In about a month the patient recovered, and Copernicus returned to Frombork. For a time, he continued to receive reports on von Kunheim's condition, and to send him medical advice by letter.

Throughout this period of his life, Copernicus continued making astronomical observations and calculations, but only as his other responsibilities permitted and never in a professional capacity.

Some of Copernicus' close friends turned Protestant, but Copernicus never showed a tendency in that direction. The first attacks on him came from Protestants. Wilhelm Gnapheus, a Dutch refugee settled in Elbl?g, wrote a comedy in Latin, Morosophus (The Foolish Sage), and staged it at the Latin school that he had established there. In the play, Copernicus was caricatured as a haughty, cold, aloof man who dabbled in astrology, considered himself inspired by God, and was rumored to have written a large work that was moldering in a chest.

Elsewhere Protestants were the first to react to news of Copernicus' theory. Melanchthon wrote:

Nevertheless, in 1551, eight years after Copernicus' death, astronomer Erasmus Reinhold published, under the sponsorship of Copernicus' former military adversary, the Protestant Duke Albert, the Prussian Tables, a set of astronomical tables based on Copernicus' work. Astronomers and astrologers quickly adopted it in place of its predecessors.

Heliocentrism

Some time before 1514 Copernicus made available to friends his "Commentariolus" ("Little Commentary"), a forty-page manuscript describing his ideas about the heliocentric hypothesis. It contained seven basic assumptions. Thereafter he continued gathering data for a more detailed work.

About 1532 Copernicus had basically completed his work on the manuscript of De revolutionibus orbium coelestium; but despite urging by his closest friends, he resisted openly publishing his views, not wishing...as he confessed...to risk the scorn "to which he would expose himself on account of the novelty and incomprehensibility of his theses."

In 1533, Johann Albrecht Widmannstetter delivered a series of lectures in Rome outlining Copernicus' theory. Pope Clement VII and several Catholic cardinals heard the lectures and were interested in the theory. On 1 November 1536, Cardinal Nikolaus von Schönberg, Archbishop of Capua, wrote to Copernicus from Rome:

Some years ago word reached me concerning your proficiency, of which everybody constantly spoke. At that time I began to have a very high regard for you... For I had learned that you had not merely mastered the discoveries of the ancient astronomers uncommonly well but had also formulated a new cosmology. In it you maintain that the earth moves; that the sun occupies the lowest, and thus the central, place in the universe... Therefore with the utmost earnestness I entreat you, most learned sir, unless I inconvenience you, to communicate this discovery of yours to scholars, and at the earliest possible moment to send me your writings on the sphere of the universe together with the tables and whatever else you have that is relevant to this subject ...

By then Copernicus' work was nearing its definitive form, and rumors about his theory had reached educated people all over Europe. Despite urgings from many quarters, Copernicus delayed publication of his book, perhaps from fear of criticism...a fear delicately expressed in the subsequent dedication of his masterpiece to Pope Paul III. Scholars disagree on whether Copernicus' concern was limited to possible astronomical and philosophical objections, or whether he was also concerned about religious objections.

The book

Copernicus was still working on De revolutionibus orbium coelestium (even if not convinced that he wanted to publish it) when in 1539 Georg Joachim Rheticus, a Wittenberg mathematician, arrived in Frombork. Philipp Melanchthon, a close theological ally of Martin Luther, had arranged for Rheticus to visit several astronomers and study with them.

Rheticus became Copernicus' pupil, staying with him for two years and writing a book, Narratio prima (First Account), outlining the essence of Copernicus' theory. In 1542 Rheticus published a treatise on trigonometry by Copernicus (later included in the second book of De revolutionibus).

Under strong pressure from Rheticus, and having seen the favorable first general reception of his work, Copernicus finally agreed to give De revolutionibus to his close friend, Tiedemann Giese, bishop of Che?mno (Kulm), to be delivered to Rheticus for printing by the German printer Johannes Petreius at Nuremberg (Nürnberg), Germany. While Rheticus initially supervised the printing, he had to leave Nuremberg before it was completed, and he handed over the task of supervising the rest of the printing to a Lutheran theologian, Andreas Osiander.

Osiander added an unauthorised and unsigned preface, defending the work against those who might be offended by the novel hypotheses. He explained that astronomers may find different causes for observed motions, and choose whatever is easier to grasp. As long as a hypothesis allows reliable computation, it does not have to match what a philosopher might seek as the truth.

Death

Copernicus died in Frauenburg on 24 May 1543. Legend has it that the first printed copy of De revolutionibus was placed in his hands 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.

Copernicus was reportedly buried in Frombork Cathedral, where archaeologists for over two centuries searched in vain for his remains. Efforts to locate the remains in 1802, 1909, 1939 and 2004 had come to nought. In August 2005, however, a team led by Jerzy G?ssowski, head of an archaeology and anthropology institute in Pu?tusk, after scanning beneath the cathedral floor, discovered what they believed to be Copernicus' remains.

The find came after a year of searching, and the discovery was announced only after further research, on November 3, 2008. G?ssowski said he was "almost 100 percent sure it is Copernicus." Forensic expert Capt. Dariusz Zajdel of the Polish Police Central Forensic Laboratory used the skull to reconstruct a face that closely resembled the features...including a broken nose and a scar above the left eye...on a Copernicus self-portrait. The expert also determined that the skull belonged to a man who had died around age 70...Copernicus' age at the time of his death.

The grave was in poor condition, and not all the remains of the skeleton were found; missing, among other things, was the lower jaw. The DNA from the bones found in the grave matched hair samples taken from a book owned by Copernicus which was kept at the library of the University of Uppsala in Sweden.

On 22 May 2010 Copernicus was given a second funeral in a Mass led by Józef Kowalczyk, the former papal nuncio to Poland and newly named Primate of Poland. Copernicus' remains were reburied in the same spot in Frombork Cathedral where part of his skull and other bones had been found. A black granite tombstone now identifies him as the founder of the heliocentric theory and also a church canon. The tombstone bears a representation of Copernicus' model of the solar system...a golden sun encircled by six of the planets.

Predecessors

Philolaus (c. 480—385 BCE), a Greek philosopher of the Pythagorean school, described an astronomical system in which the Earth, Moon, Sun, planets, and stars all revolved about a central fire. Heraclides Ponticus (387—312 BCE) proposed that the Earth rotates on its axis. According to Archimedes, Aristarchus of Samos (310—230 BCE) wrote of heliocentric hypotheses in a book that does not survive. Plutarch wrote that Aristarchus was accused of impiety for "putting the Earth in motion".

In a manuscript of De revolutionibus, Copernicus wrote, "It is likely that ... Philolaus perceived the mobility of the earth, which also some say was the opinion of Aristarchus of Samos", but later struck out the passage and omitted it from the published book.

Ptolemy

The prevailing theory in Europe during Copernicus' lifetime was the one that Ptolemy published in his Almagest circa 150 CE. Ptolemy's system drew on previous Greek theories in which the Earth was the stationary center of the universe. Stars were embedded in a large outer sphere which rotated rapidly, approximately daily, while each of the planets, the Sun, and the Moon were embedded in their own, smaller spheres. Ptolemy's system employed devices, including epicycles, deferents and equants, to account for observations that the paths of these bodies differed from simple, circular orbits centered on the Earth. Ptolemy's model was refined by the 10th-century astronomer Muhammad al Battani, working at Ar-Raqqah in modern-day Syria. Although al Battani accepted the validity of the Ptolemaic model, Copernicus made much use of his astronomical observations in demonstrating the heliocentric theory, and gave acknowledgement to his predecessor in De revolutionibus.

Copernicus

Copernicus' major theory was published in De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres), in the year of his death, 1543, though he had formulated the theory several decades earlier.

Copernicus' "Commentariolus" summarized his heliocentric theory. It listed the "assumptions" upon which the theory was based as follows:

1. There is no one center of all the celestial circles or spheres.2. The center of the earth is not the center of the universe, but only of gravity and of the lunar sphere.3. All the spheres revolve about the sun as their mid-point, and therefore the sun is the center of the universe.4. The ratio of the earth's distance from the sun to the height of the firmament (outermost celestial sphere containing the stars) is so much smaller than the ratio of the earth's radius to its distance from the sun that the distance from the earth to the sun is imperceptible in comparison with the height of the firmament.5. Whatever motion appears in the firmament arises not from any motion of the firmament, but from the earth's motion. The earth together with its circumjacent elements performs a complete rotation on its fixed poles in a daily motion, while the firmament and highest heaven abide unchanged.6. What appear to us as motions of the sun arise not from its motion but from the motion of the earth and our sphere, with which we revolve about the sun like any other planet. The earth has, then, more than one motion.7. The apparent retrograde and direct motion of the planets arises not from their motion but from the earth's. The motion of the earth alone, therefore, suffices to explain so many apparent inequalities in the heavens.

De revolutionibus itself was divided into six parts, called "books":

1. General vision of the heliocentric theory, and a summarized exposition of his idea of the World
2. Mainly theoretical, presents the principles of spherical astronomy and a list of stars (as a basis for the arguments developed in the subsequent books)
3. Mainly dedicated to the apparent motions of the Sun and to related phenomena
4. Description of the Moon and its orbital motions
5. Concrete exposition of the new system
6. Concrete exposition of the new system

Successors

Georg Joachim Rheticus could have been Copernicus' successor, but did not rise to the occasion. Erasmus Reinhold could have been his successor, but died prematurely. The first of the great successors was Tycho Brahe, followed by his erstwhile co-worker, Johannes Kepler.

See also: Catholic Church and science

At original publication, Copernicus' epoch-making book caused only mild controversy, and provoked no fierce sermons about contradicting Holy Scripture. It was only three years later, in 1546, that a Dominican, Giovanni Maria Tolosani, denounced the theory in an appendix to a work defending the absolute truth of Scripture. He also noted that the Master of the Sacred Palace (i.e., the Catholic Church's chief censor), Bartolomeo Spina, a friend and fellow Dominican, had planned to condemn De revolutionibus but had been prevented from doing so by his illness and death.

Arthur Koestler, in his popular book The Sleepwalkers, asserted that Copernicus' book had not been widely read on its first publication. This claim was trenchantly criticised by Edward Rosen, and has been decisively disproved by Owen Gingerich, who examined every surviving copy of the first two editions and found copious marginal notes by their owners throughout many of them. Gingerich published his conclusions in 2004 in The Book Nobody Read.

It has been much debated why it was not until six decades after Spina and Tolosani's attacks on Copernicus's work that the Catholic Church took any official action against it. Proposed reasons have included the personality of Galileo Galilei and the availability of evidence such as telescope observations.

In March 1616, in connection with the Galileo affair, the Roman Catholic Church's Congregation of the Index issued a decree suspending De revolutionibus until it could be "corrected," on the grounds that the supposedly Pythagorean doctrine that the Earth moves and the Sun does not was "false and altogether opposed to Holy Scripture." The same decree also prohibited any work that defended the mobility of the Earth or the immobility of the Sun, or that attempted to reconcile these assertions with Scripture.

On the orders of Pope Paul V, Cardinal Robert Bellarmine gave Galileo prior notice that the decree was about to be issued, and warned him that he could not "hold or defend" the Copernican doctrine. The corrections to De revolutionibus, which omitted or altered nine sentences, were issued four years later, in 1620.

In 1633 Galileo Galilei was convicted of grave suspicion of heresy for "following the position of Copernicus, which is contrary to the true sense and authority of Holy Scripture," and was placed under house arrest for the rest of his life.

The Catholic Church's 1758 Index of Prohibited Books omitted the general prohibition of works defending heliocentrism, but retained the specific prohibitions of the original uncensored versions of De revolutionibus and Galileo's Dialogue Concerning the Two Chief World Systems. Those prohibitions were finally dropped from the 1835 Index.

The question of Copernicus' nationality, and indeed whether it is meaningful to ascribe to him a nationality in the modern sense, has been the subject of some discussion.

Historian Michael Burleigh describes the nationality debate as a "totally insignificant battle" between German and Polish scholars during the interwar period.

Astronomer Konrad Rudnicki calls the discussion a "fierce scholarly quarrel in... times of nationalism", and describes Copernicus as an inhabitant of a German-speaking territory belonging to Poland, himself of mixed Polish-German extraction.

According to Czes?aw Mi?osz, the debate is an "absurd" projection of a modern understanding of nationality on Renaissance people, who identified with their home territories rather than with a nation.

Similarly, historian Norman Davies states that Copernicus, as was common for his era, was "largely indifferent" to nationality, being a local patriot who considered himself "Prussian".

Mi?osz and Davies both say that despite Copernicus' German-speaking background, his working language was Latin, though according to Davies there is evidence that Copernicus also knew Polish. Davies concludes: "Taking everything into consideration, there is good reason to regard him both as a German and as a Pole, yet in the sense that modern nationalists understand it, he was neither."

The Stanford Encyclopedia of Philosophy describes Copernicus as "the child of a German family [who] was a subject of the Polish crown." Encyclopædia Britannica, Encyclopedia Americana, The Columbia Encyclopedia, The Oxford World Encyclopedia, and the Microsoft Encarta Online Encyclopedia identify Copernicus as Polish.

On July 14, 2009, the discoverers, from the Gesellschaft für Schwerionenforschung in Darmstadt, Germany, of chemical element 112 (temporarily named ununbium) proposed to the International Union of Pure and Applied Chemistry that its permanent name be "copernicium" (symbol Cn). "After we had named elements after our city and our state, we wanted to make a statement with a name that was known to everyone," said Hofmann. "We didn't want to select someone who was a German. We were looking world-wide."

On the 537th anniversary of his birthday the official naming was released to the public.

Copernicus is honored, together with Johannes Kepler, in the liturgical calendar of the Episcopal Church , with a feast day on May 23.