The Christian celebration of the birth of Jesus Christ, observed on December 25.
Christmas commemorates the Nativity of Jesus Christ. Celebrated since the 4th century, it has become one of the most widely observed festivals in the world, blending religious traditions with cultural customs — gift-giving, family meals, decorated trees, carols, and acts of charity. The date of December 25 is a fixed Western Christian observance; Eastern Orthodox churches following the Julian calendar mark Christmas on January 7.
Computed for Saint-Simon (Europe/Paris) using local sunrise, sunset and astronomical positions.