February 29 takes approximately 6 hours longer than 365 whole days. A leap day compensates for this lag, realigning the calendar with the Earth's position in the Solar System; otherwise, seasons would occur later than intended in the calendar year. The Julian calendar used in Christendom until the 16th century added a leap day every four years; but this rule adds too many days (roughly 3 every 400 years), making the equinoxes and solstices shift gradually to earlier dates. By the 16th century the vernal equinox had drifted to March 11, and the Gregorian calendar was introduced both to shift it back
Aztec New Year 22nd. This 365-day calendar was corresponded with the solar year, was divided into 18 'months' of 20 days each, plus 5 'nameless' days at the end of the year. Also, there are some codices that show the existence of the leap year. Aztec New Year The Aztec New Year ( or "Año Nuevo Azteca"; , ) is the celebration of the new year according to the Aztec calendar. The date on which the holiday falls in the Gregorian calendar depends on the version of the calendar used, but it is generally considered to occur at sunrise on March 12. The