Leapingest Leap Year Ever

By William L. Steen

(From The Calendar: Its History, Structure and Improvement by Alexander Phillip, Cambridge University Press; other sources.)

Let there be lights … to divide the day from the night, and let them be for signs, and for seasons, and for days, and for years (Moses 2:14).

On Thursday, February 29, 1996, you could be sitting in school wondering, Weren’t there only 28 days in February last year? And you’d be right.

Every fourth year (except for years that end in 00 and that cannot be divided evenly by 400) an extra day is added to February, and that year is called leap year. It’s been done that way for over 2,000 years. So one additional day, even if it’s a school day, isn’t a big deal.

At least, it isn’t as big a deal as the year that started the leap year tradition. That year, 46 B.C., could be described as the leapingest leap year in history. It didn’t have just one extra day, or two, or ten, or twenty, or even fifty extra days. The year 46 B.C. had eighty extra days, and they were probably all school days!

Why are there leap years? It takes the earth about 365 and 1/4 days to travel around the sun. If you were making a calendar, what would you do with the extra 1/4 day?

You could put it in one year and the other 3/4 of a day in another year. For example, if 1996 started at midnight on New Year’s Eve, 1997 would start 365 and 1/4 days later, at 6:00 A.M. on January 1. Sounds confusing, doesn’t it?

Or you could just ignore the extra 1/4 day and make every year 365 days long. The only problem is that the calendar would fall behind the solar year by 1/4 day every year. Eventually summer would come during the winter months.

Julius Caesar tried to solve the problem when he was the leader of the Roman Empire. The calendars were a mess because the leader of any nation could make the calendar longer or shorter any time he felt like it. There might be ten months or twelve or thirteen. With this type of calendar, it was easy to make mistakes.

Julius Caesar didn’t want a calendar full of mistakes. He wanted one that was accurate. He decided that the only way to correct the calendar was to make a new one. But what about the extra 1/4 day? He finally decided the best thing to do was make each year 365 days long. Then every four years, when the calendar had fallen a whole day behind, add a leap day to make up the missing time.

At first this leap day was added between February 23 and February 24. It wasn’t considered an official day, so they didn’t bother to give it a number. If you happened to be born on the day with no number, you celebrated your birthday on February 24. Later, the extra day was added at the end of the month as February 29.

Julius Caesar had another problem to solve before he could introduce his new calendar. The Romans were very sloppy calendar keepers. After constantly changing the calendar for hundreds of years, the months were no longer in their proper seasons.

His solution to this mess was the leapingest leap year in history. He decided to add all the days that had been left out. To do this, he made 46 B.C. one giant leap year. First, he added a 23-day month, which he called Mercedonius, after the month of February. Then he added two more months between November and December, making that year 445 days long! Although Julius Caesar’s fifteen-month year did return the months to their correct seasons, the Romans called it “the year of confusion.”

If you are tempted to complain about going to school an extra day this February, just remember the leapingest leap year in history. You are still seventy-nine days luckier than the children who lived in 46 B.C.

Illustrated by Shauna Mooney Kawasaki