So how is your ancient Egyptian trivia? Up to par, or not what it could be? Mine just got expanded, and if you're not careful reading this, you might learn something, too (that's a Fat Albert joke for you kids out there.)
The ancient Egyptians were all about the stars and astrology. Not only were they completely aware of the seasons and the progression of the planets, they're the same folk who gave us the zodiac symbols. And they weren't just pretty darn good astronomers and architencts, they also used a calendar that matched the revolution of the Earth around the sun. Their calendar, like ours, had twelve months. Their calendar, like ours, even included regular divisions of weeks. Their calendars unlike ours only accounted for three hundred sixty days, though, so the last five days of the year were set aside for partying and worshiping their pantheon of gods and pharoahs and all that good stuff. Also unlike our calendar, their months consisted of THREE weeks, each ten days long.
Three ten-day long weeks. Imagine what a work week that must have been! Three more days of working your fingers to the bone at the marble yard, being baked in the desert heat, chiseling and carving and sanding so Ramses The Living God could have a new portico for his vacation pyramid. You get to go home two days to rest and recouperate, maybe have some goat's milk beer from the local brewmaster, and then right back to work for eight more days.
Those guys sure were slave drivers. (that's a little joke there)
The other interesting thing is this--their calendar only accounted for 365 days, and not the extra 1/4 of a day that occurs year in one complete orbit of Earth. We have Leap Day every four years to account for those lost quarters, but the Egyptians didn't realise anything was amiss until their seasons no longer matched their calendar.
So what did they do? In typical bureaucratic fashion they simply instated ANOTHER calendar, so that there were two--one for the people, and one for the holy days and their attendant gods.