(February 18, 1201 – June 26, 1274)
Astute, versatile and improvising, this prime genius was among the greatest intellectuals of the Islamic Golden Age. As a jack-of-all-trade and master-of-all, he worked in diverse fields of arts and sciences. Nasir al-Din al-Tusi is remembered today as the first person who demonstrated that Trigonometry is independent of Astronomy. His Treatise on the Quadrilateral unveiled Spherical Trigonometry in a manner neither seen nor contemplated before. Due to these, he is rapturously referred to as the “Father of Trigonometry”. He developed his acclaimed Tusi Couple, which was a geometrical contrivance that effectively replaced the cumbersome Ptolemy’s Equant. His planetary motions essays (plus accurate calculations of equinoxes) were indispensable to Copernicus, who used them as basis for investigating the unknown realms of astrophysics. His bio-research showcased some of the earliest forages into both genetics and taxonomy. He classified living organisms into plants, animals and humans. As avid reader of Avicenna’s works, Tusi was inspired to follow in his footsteps. From mathematics to medicine, and chemistry to physics, his tireless research ushered-in some of the knowhow which foreshadowed Renaissance and the centuries of discoveries that followed it. For example, this asseveration: “A body of matter cannot disappear completely. It only changes its form, condition, composition, color and other properties and turns into a different complex or elementary matter”, which is attributed to Tusi, precedes our contemporary Law of Conservation of Mass. As tributes to his accomplishments, both the 60-kilometer-wide Nasireddin lunar crater and the 10269 Tusi minor planet are named after him.