Leap Year 2024: The Importance of One Extra Day and Its Importance for Us
We mark each leap year with an additional day added to the calendar every four years. In addition, 2024 will be a leap year, featuring 29 days in February as opposed to 28. However, why is this change necessary, and what would happen if we didn’t follow it? This article will examine the history, significance, and practical applications of leap years in relation to timekeeping and seasonal awareness.
Because of this irregularity in the length of the Earth’s orbit around the Sun, leap years are seen.
An orbit around the Sun takes the Earth about 365.2425 days to complete. This indicates that our calendar is always around six hours behind Earth’s real location each year. We add a day every four years to make up for this disparity, producing a year that is 366 days long. Leap day is the name given to an additional day that is added to February, extending its duration from 28 to 29 days.
The rotation of Earth
However, how can we determine which year is a leap year? A year is a leap year if it is divisible by 4, unless it is also divisible by 100, in which case it is not, and if it is also divisible by 400, in which case it is. This is the straightforward rule. 2024, for instance, is a leap year because its square root is 4. However, since 2100 is divisible by 100 rather than 400, it is not a leap year. But because 2000 is divisible by 400, it was a leap year.
Pope Gregory XIII instituted this regulation in 1582, when he modified the Julian calendar, which had been in use since 45 BCE. The Julian calendar had a more straightforward rule: a leap year is any year that is divisible by 4. But this resulted in an excessively lengthy calendar each year—roughly eleven minutes and fourteen seconds. This inaccuracy grew over time until, by 1582, the calendar was 10 days ahead of Earth’s real position3. Pope Gregory XIII corrected this by adding 10 more days to the calendar and instituting the current leap year system, which is more precise and closely aligned with the actual duration of the year.
The Gregorian calendar, which we still use today, was established by Pope Gregory XIII in 1582. iStock
However, why is the accuracy of the calendar important to us? Keeping the seasons in line with the calendar is the primary motivation. The tilt of the Earth’s axis, which results in varying quantities of sunlight reaching various regions of the planet year-round, determines the seasons.
The seasons begin on the equinoxes and solstices, which fall on certain calendar days. However, the seasons will progressively stray from their customary dates if the calendar is not in line with Earth’s orbit. Without leap years, the summer solstice, for instance, would fall on June 21 rather than June 20 after 100 years and on July 20 after 700 years. This would impact when festivals, holidays, and other seasonally-dependent events take place, as well as agricultural activity.
Leap years are thus necessary to maintain the balance between our calendar and the planet. They assist us in marking significant occasions in our lives and in keeping track of time and the seasons. 2028 is the next leap year, and February 29, 2028, is the next leap day. So take advantage of the additional day and mark your calendars!
