We’re getting an extra day this year! This upcoming Thursday, February 29th, 2024, will be a leap day, which is an added 24-hour day to the calendar year that occurs roughly every four years. The purpose of leap years is to keep our human-made calendar aligned correctly with the natural rhythm of the seasons.
An article from PBS discusses the history and origin of the unofficial holiday called Leap Day. In 45 BCE, Roman dictator Julius Caesar developed a solar calendar that adds an extra day to February, the shortest month of the year, every 4 years. This adjustment was made to ensure that our easons don’t drift out of sync.
In leap years, there are 366 days in a year instead of 365 days. The extra day is added since it takes the earth 365.242190 days to orbit the sun, which equals 365 days 5 hours 48 minutes and 56 seconds. A leap day is added to account for that extra 5 hours 48 minutes. Without leap years the seasons would begin to shift and winter weather could begin to occur in June.
Adding a leap year every 4 years would result in a calendar that is too long by 44 minutes. These extra 44 mins would also cause the seasons to drift in our calendar. Due to this, there can not be a leap day every 4 years. Here are the rules to know which years are leap years:
- If the year is evenly divisible by 4
- Years divisible by 100 can not be leap years unless they are also divisible by 400.
The next few leap years will take place in 2024, 2028, 2032, and 2036.
You may be wondering when someone who was born on leap day celebrates their birthday. Most individuals with leap day birthdays celebrate their birthday on either Feb. 28 or March 1 during non-leap years. During leap years, including this year, those who have leap day birthdays will be able to celebrate their birthday on the actual day they were born.
According to the article, “Learn How Leap Years Keep Our Calendar Accurate” by Catherine Boeckmann, Leap Day birthdays are the rarest birthdays to have in the Gregorian calendar. The probability of a leap day birthday is 1/1461, meaning less than 0.07% of the world’s population was born on leap day.
Leap Day became a day of traditions and superstitions over 2000 years ago. An article titled “Leap Day Customs & Traditions” by Vigdis Hocken states that Leap Day was formerly used as a day where women can propose to men, which was known as “Ladies Day”. This was done as a way to balance the traditional roles of men and women, similarly to leap years balancing the calendar.
In many European countries, it was a tradition that any man who refuses a woman’s proposal on February 29 has to buy her 12 pairs of gloves. The intent behind this was that the woman can wear the gloves to hide the embarrassment of not having an engagement ring.
Take a moment this Thursday, February 29, 2024, to appreciate the extra day we are receiving. Leap Day is not only an important unofficial holiday that keeps our calendar and seasons aligned, this day is also known for its traditions and superstitions.