Leap Day helps keep calendar in sync


Every four years an extra day is added to the calendar in February, though few actually know why.

A Leap Year happens in order to keep the calendar year synchronized with the astronomical or seasonal year. 

Borgna Brunner, writer for the online almanac InfoPlease, said this is also because the Earth does not orbit around the sun in exactly 365 days. The extra day is added to keep years from drifting through the seasons and events. For example, the extra day helps keep Christmas on the correct date.

“It may not seem like much of a difference, but after a few years those extra quarter days in the solar year begin to add up,” Brunner said.

Leap Year means more to some people than it does to others. Westland freshman Michaela North will spend Feb. 29 celebrating her birthday.

Everyone who has a birthday on Leap Day celebrates it differently, but North has always celebrated on Feb. 28 because she believes she was born in February for a reason. 

“Having a Leap Day birthday doesn’t affect me much; to me it's just another day, but it's still exciting when that one year finally rolls around and the 29th is here,” North said.

She called being a Leap Day baby "exciting" and said it was fun to joke about how old she is because her birthday is only once every four years.

The government recognizes that every person has one birth date, however, for leap day babies, the government says that they have a birthday on Feb. 29 and March 1; they add March 1 because it is the day that follows Feb. 28.

Physics faculty member Glen Williams said our Gregorian Calendar is based off of a Tropical Year, which goes from one Vernal Equinox to the next. It is 365.24 days long, and the extra one-fourth of a day is why leap days are added every four years.

“We do this because we want the first day of spring to fall on, or near, March 21 of each year,” Williams said.

A calendar with leap days was first introduced in 45 B.C. by Julius Caesar, called the Julian Calendar. Williams said this worked well until the Middle Ages, when the calendars starting going out of sync with the seasons by ten days.

It wasn't until 1582 that Pope Gregory XIII created the calendar we still use today, called the Gregorian Calendar. Other than it adding a leap day every four years, it also has two other rules. One rule is that if a year is divisible by 100, but not 400, then it is not a leap year. For instance, the years 1700, 1800 and 1900. The other rule is that if a year is divisible by 400, it is a leap year. For example, the year 2000 was a leap year.

The Gregorian Calendar gives each year an average length of 365.24 days, which is much more accurate than the Tropical Year was.

“This calendar will only get out of sync with the seasons by one day in 3,000 years,” Williams said.

There was one problem with the new calendar. In 1582 Pope Gregory said Oct 15 would follow Oct 4, so the calendar would go back in sync with the seasons.

“People started to riot because they thought that the Pope was shortening their lives by 10 days,” Williams said.