- which was Passover...
When the Gregorian calendar was enforced by the rulers of the Earth, our lives were irrevocably synchronized with the planetary orbits. But the Church refused to alter the Movable Feasts, so we still have Easter on the Sunday following the first full moon occuring on or after what had been Passover when the decision was made to change the calendar: March 21st. The Julian Calendar, as used after Rome fell, was pretty strange by modern standards. Newyears Day floated all over the place, whereas now it is always December 21 - yes, it's not January 1st, since Newyears Day is the day when the days stop getting shorter (meaning that Year was leaving us to Dark), and begin getting longer (meaning that we were lucky enough to have gotten the Year to stay and begin increasing the length of days for another few months.) Of course we're all taught to call that day the first day of Winter, and the day one week after Christmas is called Newyears Day - but that's not quite right.
I've provided you with a table, explaining the whole schedule until the Millennium (1/1/2001):
See how long until the Millennium (1/1/2001), in days, hour, seconds, and milliseconds:
If you want a LOT of detail about the calendar, feel free to read the Cornell FAQ on calendars:
If you want a LOT of detail about the recording time, feel free to brouse the ISO 8601 page.
If you want to know about Blue Moons, go for it!