1502-1578

Portuguese mathematician, astronomer, and cosmographer whose work helped maintain the Portuguese Empire. As mathematics professor, Nunes pioneered mathematical education for low-status navigators and ship pilots, while also serving as tutor for the brothers of King John III. From his astronomical research, Nunes invented the nonius, enabling mariners to measure fractions of degrees in finding their latitude. Cosmographically, Nunes' distinction between rhumb lines and great circles predates Gerardus Mercator's more famous incorporation of this distinction into map projections.