Articles on the Gregorian and Julian calendars, the ISO date format, the Julian day number system, the Maya calendar, the Goddess lunar calendar, the Liberalia Triday Calendar and C functions for date conversion; plus software for calendrical conversion.
The calendar was the center of Maya life and their greatest cultural achievement. To carry out their astronomical calculations they developed a sophisticated mathematical system. The Maya Calendar website is developing with the intent of providing a complete view of Maya culture.
Lunar calendar with lunations, from new moon to new moon, instead of months. Moon phase on each day. Chinese, Jewish, and Islamic months. Eclipses, meteors, planets, star charts. Christian, Pagan, Islamic, Hindu, and Jewish holidays.
Explanations of the Julian Calendar, the Gregorian Reform, the adoption of the Gregorian Calendar, the length of the tropical year and related matters.