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Why Leap Year

Calm down, calm down, it's not a leap year. That won't happen until 2020 when we see another election and the Summer Olympics. We just got to thinking one day, why leap year? The origins of the leap year date back to 46 BC, when Julius Caesar, under the influence of Sosigenes of Alexandria, introduced the Julian calendar. According to them, a year was considered to be not just 365 days, but actually 365.25 days (hence the need for a leap day/year). But what they didn't realize is that the Tropical year (the time it takes the planet to make one revolution around the sun) is actually slightly less than that (about 365.242), and over a period of 400 years, the Julian calendar would end up having an extra 3 days. This meant certain astronomical events, like the Vernal Equinox, and festivals associated with such evens, like Easter, occurred out of sync with respect to their fixed dates. By the year 1582, the difference in time had accumulated, and the calendar had fallen so out of sync with the Tropical year, it was off by 10 days! To fix this, Pope Gregory XIII, under the influence of astronomer Christopher Clavis, produced the modern Gregorian calendar we know today to correct this error by simply omitting those 10 days. Which meant that after Thursday, October 4, 1582, the next day was Friday, October 15, 1582. Which meant October 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, in 1582 technically never happened. Google it! Apparently there were riots in Europe because people felt like 10 days were taken away from their lives. Crazy. Anyway, that's why we have a leap year. But to compensate for the extra 3 days every 400 years, the Pope also added a rule that every century which is not divisible by 400 will not be a leap year. So the year 2000 was a Leap Year, but 2100 won't be. Makes sense, right? Note: even the Gregorian calendar is still off. Every 3236 years, the calendar gains an extra day. Clipper Mill