Khayyam's tomb

Omar Khayyam was a Persian polymath, mathematician, astronomer, historian, philosopher, and poet. He was born in Nishapur, the initial capital of the Seljuk Empire. As a scholar, he was contemporary with the rule of the Seljuk dynasty around the time of the First Crusade.

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.: 284  As an astronomer, he designed the Jalali calendar, a solar calendar with a very precise 33-year intercalation cycle: 659  that provided the basis for the Persian calendar that is still in use after nearly a millennium.