Ghiyāth al-Dīn Abū al-Fatḥ ʿUmar ibn Ibrāhīm Nīsābūrī[3][4] (18 May 1048 – 4 December 1131), commonly known as Omar Khayyam (Persian: عمر خیّام),[a] was a Persian[5] polymath, known for his contributions to mathematics, astronomy, philosophy, and poetry.[6] 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.[7] Khayyam also contributed to the understanding of the parallel axiom.[8]: 284  As an astronomer, he calculated the duration of the solar year with remarkable precision and accuracy, and designed the Jalali calendar, a solar calendar with a very precise 33-year intercalation cycle[9][10]: 659  that provided the basis for the Persian calendar that is still in use after nearly a millennium.

There is a tradition of attributing poetry to Omar Khayyam, written in the form of quatrains (rubāʿiyāt رباعیات). This poetry became widely known to the English-reading world in a translation by Edward FitzGerald (Rubaiyat of Omar Khayyam, 1859), which enjoyed great success in the Orientalism of the fin de siècle.

NB: May 18, 1048 Julian ~ May 24, 1048 Gregorian

Source: https://en.wikipedia.org/wiki/Omar_Khayyam