RENAISSANCE ASTRONOMY COPERNICUS

1. RENAISSANCE ASTRONOMYCOPERNICUS • NICOLAUS COPERNICUS (1473-1543) • BORN TO A WEALTHY FAMILY IN TORUN, POLAND • HIS FATHER DIED WHEN HE WAS IN HIS EARLY TEENS - HIS UNCLE, BISHOP OF VARMIA, SAW TO HIS EDUCATION • WENT TO THE UNIVERSITY OF CRACOW IN 1491 TO STUDY ASTRONOMY AND ASTROLOGY • ELECTED CANON OF THE CATHEDRAL AT FROMBORK – WENT TO BOLOGNA TO STUDY CANON AND LAW WHERE HE LODGED AND WORKED WITH DOMENICO MARIA THE FERRARESE OF NOVARA, PROFESSOR OF MATHEMATICS • ATTENDED UNIVERSITY OF PADUA (1501-1503) TO STUDY MEDICINE • MOVED TO THE UNIVERSITY OF FERRAR WHERE HE OBTAINED A DOCTORATE IN CANON LAW IN 1503 • LEARNED GREEK IN ORDER TO BETTER STUDY ASTRONOMY • HE WAS FLUENT IN POLISH, LATIN, GERMAN, GREEK AND ITALIAN

2. COPERNICUS’ TALENTS • ASTRONOMER/ASTROLOGER • PHILOSOPHER • MATHEMATICIAN • THEOLOGIAN • MEDICAL DOCTOR • LAWYER • POET • POLITICIAN

3. COPERNICUS CONTINUED • HE BECAME REKNOWNED AS A MATHEMETICIAN – AS EARLY AS 1500 HE LECTURED TO LARGE AUDIENCES • SHORTLY AFTER 1503 WHEN HE RETURNED TO POLAND HE WROTE COMMENTARIOLUS (LITTLE COMMENTARY) IN WHICH HE SET OUT THE POSTULATES OF A SUN-CENTERED COSMOLOGY. • IN 1514 THE LATERAN COUNCIL SOUGHT HIS OPINION REGARDING THE CALENDAR (IT WAS REFORMED UNDER THE DIRECTION OF POPE GREGORY XIII IN 1582) • BY THE 1530’S HIS FAME AS A MATHEMATICIAN REACHED THE VATICAN • GEORG JOACHIM RHETICUS, PROFESSOR OF MATHEMATICS AT THE UNIVERSITY OF WITTENBERG, VISITED COPERNICUS IN 1539.

4. COPERNICUS CONTINUED • RHETICUS PUBLISHED NARRATIO PRIMA (FIRST REPORT ON THE BOOKS OF REVOLUTION) IN 1540 • IN IT WE SEE THE FIRST DESCRIPTION OF COPERNICUS’ HELIOCENTRIC THEORY. • RHETICUS, AS ALMOST ALL OTHER ASTRONOMER/MATHEMATICIANS OF THE TIME, REGARDED PTOLEMY’S EQUANTS WITH DISDAIN • RHETICUS SAID THE EQUANT WAS “A RELATION THAT NATURE ABHORS”

5. De revolutionibusorbiumcoelestium (On the Revolutions of the Celestial Spheres) • WHEN THE PUBLICATION OF RHETICUS’ FIRST REPORT STIRRED LITTLE CONTROVERSY COPERNICUS ALLOWED HIM TO TAKE HIS COMPLETE WORK DE REVOLUTIONIBUS TO NUREMBERG FOR PRINTING • OSIANDER, A LOCAL LUTHERAN CLERGYMAN, OVERSAW THE PRINTING. • HE INSERTED AN UNSIGNED FORWARD WHICH DISCLAIMED THE HELIOCENTRIC HYPOTHESIS STATING THAT IT WAS JUST A GOOD WAY TO DO CALCULATIONS. • IT WAS PUBLISHED IN 1543, THE YEAR COPERNICUS DIED • ONE PROBLEM WITH THE HELIOCENTRIC HYPOTHESIS WAS THAT “STELLAR PARALLAX” COULD NOT BE OBSERVED. THE ONLY WAY OUT WAS, AS WITH ARTISTARCHUS, TO “BANISH THE STARS TO AN INDEFINITELY LARGE DISTANCE”. • MOST OF BOOK WAS “DAUNTINGLY MATHEMATICAL” SO NOT MANY ASTRONOMERS ATTEMPTED TO CRITIQUE COPERNICUS’ “COSMOVISION”. THEY JUST WANTED TO “CHERRY PICK” IT TO GET THE MORE ACCURATE POSITIONS OF THE PLANETS WHICH IT CONTAINED.

6. COPERNICUS HELIOCENTRIC THEORY • SUN AT THE CENTER OF THE UNIVERSE • PLANETS (INCLUDING THE EARTH) UNIFORMLY ORBITED THE SUN IN CIRCULAR ORBITS • THE MOON UNIFORMLY ORBITED THE EARTH IN A CIRCULAR ORBIT • BOTH THE PLANETS AND THE MOON ORBITED ON EPICYCLES WHICH WERE REQUIRED TO EXPLAIN THE NON-UNIFORMITY OF THEIR MOTIONS

7. COPERNICUS HELIOCENTRIC THEORY • STRENGTHS • BROUGHT COHERENCE AND “BEAUTY” TO PLANETARY COSMOLOGY • EXPLAINED RETROGRADE MOTION OF THE PLANETS AS A NATURAL OUTCOME OF THE THEORY • GREATLY REDUCED THE SIZES (NOT THE NUMBERS) OF EPICYCLES NEEDED TO DESCRIBE THE ORBITS OF THE PLANETS • EXPLAINED HOW THE “PERIOD OF THE SUN” MYSTERIOUSLY APPEARED IN THE ORBITS OF ALL OF THE PLANETS • WEAKNESSES • STILL REQUIRED EPICYCLES – IN FACT HIS SYSTEM REQUIRED NEARLY AS MANY EPICLYCLES AS PTOLEMY’S • COPERNICUS IS CRITICIZED, SOMETIMES MORE THAT PTOLEMY. EPICYCLES AS PTOLEMY THOUGHT OF THEM WERE MERELY A MATHEMATICAL CONSTRUCT WHEREAS SOME CLAIM THAT COPERNICUS VIEWED THEM AS BEING PHYSICAL.

8. COPERNICUS QUOTE PAST ASTRONOMERS “HAVE NOT BEEN ABLE TO DISCOVER OR TO INFER THE CHIEF POINT OF ALL – THE STRUCTURE OF THE UNIVERSE AND THE TRUE SYMMETRY OF ITS PARTS. BUT THEY ARE JUST LIKE SOMEONE TAKING FROM DIFFERENT PLACES HANDS, FEET, HEAD, AND OTHER LIMBS, NOT DOUBT DEPICTED VERY WELL BUT NOT MODELED FROM THE SAME BODY AND NOT MATCHING ONE ANOTHER – SO THAT SUCH PARTS WOULD PRODUCE A MONSTER RATHER THAN A MAN.

9. MARTIN LUTHER QUOTE People gave ear to an upstart astrologer who strove to show that the earth revolves, not the heavens or the firmament, the sun and the moon.... This fool wishes to reverse the entire science of astronomy; but sacred Scripture tells us [Joshua 10:13] that Joshua commanded the sun to stand still, and not the earth.

10. THE CATHOLIC CHURCH BANNED READING AN UNEDITED VERSION OF DE REVOLUTIONIBUS FOR MORE THAN 200 YEARS WHEN, IN 1758, POPE BENEDICT XIV REMOVED IT FROM THE BANNED READING LIST.

11. Historians long believed that, at its first publication, De revolutionibus had not been widely read. Owen Gingerich, a widely recognized authority on both Nicolaus Copernicus and Johannes Kepler, disproved this after a 35-year project to examine every surviving copy of the first two editions. Gingerich showed that nearly all the leading mathematicians and astronomers of the time owned and read the book; however, his analysis of the marginalia shows that they almost all ignored the cosmology at the beginning of the book and were only interested in Copernicus' new equant-free models of planetary motion in the later chapters. Also, NicolausReimers in 1587 translated the book into German. • Gingerich's efforts and conclusions are recounted in The Book Nobody Read, published in 2004 by Walker & Co. The research behind this book earned its author the Polish government's Order of Merit in 1981. Due largely to Gingerich's scholarship, De revolutionibus has been researched and catalogued better than any other first-edition historic text except for the original Gutenberg Bible.[17]

12. THE GREGORIAN CALENDAR • THE LENGTH OF THE TROPICAL YEAR IS 365.242199 DAYS • DIFFERS FROM THE JULIAN CALENDAR 365.25 DAY YEAR BY ABOUT 11 MINUTES. • IN MEDIEVAL EUROPE THE VERNAL EQUINOX WAS OCCURRING AS MANY AS 10 DAYS EARLY (AFFECTED THE DATE OF EASTER) • IN 1582 POPE GREGORY ISSUED A PAPAL BULL ANNOUNCING THAT THE YEAR 1583 WOULD BEGIN A NEW CALENDAR (WHICH WE CALL THE GREGORIAN CALENDAR) • The last day of the Julian calendar was Thursday, 4 October 1582 and this was followed by the first day of the Gregorian calendar, Friday, 15 October 1582 (the cycle of weekdays was not affected). • ENGLAND AND ITS COLONIES DIDN’T ADOPT THE GREGORIAN CALENDAR UNTIL 1752. BY THEN THE JULIAN CALENDAR HAD GOTTEN FARTHER OF TRACK SO THAT 11 DAYS HAD TO BE ADDED. • Wednesday, 2 September 1752 was followed by Thursday, 14 September 1752 • GEORGE WASHINGTON WAS BORN ON FEBRUARY 11 , 1731. WITH CALENDAR REFORM IT BECAME FEBRUARY 22, 1731

13. LEAP YEAR RULES • JULIAN CALENDAR • EVERY YEAR EVENLY DIVISIBLE BY 4 WILL BE CONSIDERED A LEAP YEAR. TO IT WE WILL ADD AN EXTRA DAY TO FEBRUARY. THE YEAR LENGTH BECAME 365.25 DAYS. IT RAN FAST ABOUT ONE DAY PER 130 YEARS. • GREGORIAN CALENDAR • LEAP YEARS WILL BE DETERMINED USING THE JULIAN CALENDAR UNLESS IT IS A CENTURY YEAR. CENTURY YEARS WILL BE LEAP YEARS ONLY IF THEY ARE EVENLY DIVISIBLE BY 400. THE YEAR LENGTH BECAME 365.2425 DAYS. ITS RUNS SLOW ABOUT ONE DAY PER 3,200 YEARS.