A Passion for Calendars -- From the Maya to Mars

How many days were there in 1752?  Is there a year 0?  When was there a February 30th?  Why did an aluminum company lose $1,000,000 on New Year's Eve?  Who thinks 1900 was a leap year?  Why is Passover late?  Why does Ramadan end early?  Does the Chinese calendar follow a 19 year cycle?  Why do the Hindus skip days and months?  Who would pay for a Martian calendar?   This talk will answer these ten questions and explain the underpinnings of the major types of calendars: solar (Gregorian, Julian, Persian, Hindu); lunar (Islamic); lunisolar (Chinese, Hebrew, Hindu); cyclical (Mayan, Balinese).  It will concentrate on computational features of calendrical calculations, but also dwell on historical and cultural aspects.