Georg Joachim RheticusBorn 16 Feb 1514; died 4 Dec 1576 at age 62.German astronomer and mathematician who was among the first to adopt and spread the heliocentric theory of Nicolaus Copernicus. He was first taught by his father, a physician, who was beheaded for sorcery (1528) while Rheticus was still a teenager. He is best known as the first disciple of Copernicus. In 1540, Rheticus published the first account of the heliocentric hypothesis which had been elaborated by Copernicus, entitled Narratio prima, which was explicitly authorised by Copernicus, who also asked for his friend's aid in editing the edition of his De revolutionibus orbium coelestium (“On the revolutions of the heavenly spheres”). Rheticus was the first mathematician to regard the trigonometric functions in terms of angles rather than arcs of a circle.[DSB gives death date 4 Dec 1574. EB gives 5 Dec 1576.] |