On February 16, 1514, mathematician, cartographer, navigational-instrument maker, medical practitioner, and teacher Georg Joachim Rheticus was born. He is perhaps best known for his trigonometric tables and as Nicolaus Copernicus’s  sole pupil, who facilitated the publication of his master’s famous work De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres).
Georg Joachim Rheticus was the son of a doctor and government official. He was taught by his father in his early life, but when the young Rheticus was only 14 years old, his father was charged for sorcery and was behaeded. The boy was then highly supported by Achilles Gasser, who took over his father’s medical practice. He helped Rheticus to begin his studies at the Latin school in Feldkirch, continuing his education in Zurich. Georg Joachim Rheticus entered the University of Wittenberg around 1533 and received his M.A. three years later. 
Rheticus was then appointed teacher of mathematics and astronomy at the University of Wittenberg after he received his degree. He was back then supported by Philipp Melanchthon, who also helped Rheticus to study with the leading astronomers at the time. In 1538, Rheticus traveled to Nuremberg where he met Johann Schöner  and the printer Petreius. In Ingolstadt, Rheticus visited Peter Apianus and went on to Tübingen in order to meet Joachim Camerarius. In the Spring of 1539, Rheticus arrived at Frauenburg in Ermland where he studied for two years with Copernicus. And experience he remembered as following:
I heard of the fame of Master Nicolaus Copernicus in the northern lands, and although the University of Wittenberg had made me a Public Professor in those arts, nonetheless, I did not think that I should be content until I had learned something more through the instruction of that man. And I also say that I regret neither the financial expenses nor the long journey nor the remaining hardships. Yet, it seems to me that there came a great reward for these troubles, namely. that I, a rather daring young man compelled this venerable man to share his ideas sooner in this discipline with the whole world. 
In 1539, the Narratio Prima was published. It is believed that to this day, the work remains the best introduction to Copernicus’s work. Rheticus managed to put himself in favor with the Duke Albert of Prussia and asked successfully for the permission to publish Copernicus’s De Revolutionibus. In 1541, Rheticus returned to the University of Wittenberg, where he was elected dean of the Faculty of Arts. In the same year, he published the trigonometrical sections of Copernicus’s De Revolutionibus, adding tables of sines and cosines, however, not naming them this way. [1,2]
One year later, Rheticus left Wittenberg for Nuremberg, where he supervised the printing of De Revolutionibus, but continued his journey to Leipzig before the work was finished. He began his teaching position in Leipzig as the professor of higher mathematics. Rheticus managed to publish a calendar and ephemeris of 1550 and also an ephemeris and calendar of 1551. In 1551 however, the scientist was forced to leave Leipzig because he was suspected of having a homosexual affair with a student. Now even Melanchton turned away from Rheticus and he was sentenced to 101 years in exile.
Rheticus then managed to study medicine in Prague and moved to Kraków where he became a practicing doctor, but he continued with his famous trigonometric tables and made instruments which he used for observations and experiments. He also earned significant merits through his 10-digit tables of trigonometric functions, which progressed from 10 to 10 seconds, but the calculation of which was only completed by his pupil Valentin Otho, who also published them in the Opus palatinum de triangulis (Heidelberg 1596). [2,3]
At yovisto, academic video search you can learn more about the scientific, social and religious impact of the Copernican Revolution with the lecture ‘Mathematics, Motion, and Truth: The Earth goes round the Sun‘ by Jeremy Gray of Gresham University.
References and Further Reading:
-  Das war Georg Joachim Rheticus
-  O’Connor, Robertson: Georg Joachim von Lauchen Rheticus
-  Georg Joachim Rheticus at Britannica
-  Nikolaus Copernicus and the Heliocentric Model, SciHi Blog, February 19, 2013.
-  Johannes Schöner and his Globes, SciHi Blog, January 16, 2015.