Omar Khayyám, Persian poet, astronomer, mathematician, and philosopher (b. 1048)
Omar Khayyam (; Persian: عمر خیّام [oˈmæɾ xæjˈjɒːm]; 18 May 1048 – 4 December 1131) 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. In the 1000s in Persia, Khayyam announced in 1079, that the length of the year was measured as 365.24219858156 days. Given that the length of the year is changing in the sixth decimal place over a person's lifetime, this is outstandingly accurate. For comparison the length of the year at the end of the 19th century was 365.242196 days, while today it is 365.242190 days.
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.