Old gravestone of Omar Khayyam

Omar Khayyam was a Persian mathematician, astronomer, philosopher, and poet. He was born in Nishapur, in northeastern Persia, and was contemporary with the rule of Seljuks around the same time the First Crusade unfolded.

As a mathematician, he is most notable for his work on the classification and solution of cubic equations, where he provided geometric solutions by the intersection of conics. Khayyam also contributed to the understanding of the parallel axiom. As an astronomer, he designed the Jalali calendar, a solar calendar with a very precise 33-year intercalation cycle that provided the basis for the very calendar that is still in use after a millennium since his works.