ENID, OK - In the year 2024 we have a February 29. It's that extra day in February that magically appears every four years. Did you know that February 29 comes in the same year as the presidential election and the Summer Olympics? That will help you remember when the extra day is coming.
Why is there an extra day every four years and who picked February 29 as that day?
The quick and simple reason is that our yearly calendar in made up of 365 days. The problem with calendars is that they do not take into consideration hours, minutes and seconds. The time that the Sun actually takes to return to the same position in the cycle of seasons is called a tropical year and it is approximately 365 days, 5 hours, 48 minutes, 45 seconds.
Those extra 5 hours, 48 minutes, 45 seconds need to be made up somewhere or our yearly calendar dates would eventually stop coinciding with the tropical year. Meaning, both calendar year and tropical year want the seasons to begin and end at the same time every year.
Julius Caesar had astronomer Sosigenes tweak the original Roman calendar to make up for the discrepancy. The astronomer decided on a 365-day year with an extra day every four years to account for the extra hours, and so February 29th was born. The reason February 29 was chosen basically comes down to the fact that February had the fewest days at that time (that's a whole other story).
The Caveat
Although most of us consider there to be a leap year every four years that's not exactly true. There's actually a leap year every year that is divisible by four, except for years that are both divisible by 100 and not divisible by 400. This extra rule about centuries was an additional fix to make up for the fact that an extra day every four years is slightly too much of a correction. The year 2000 was a leap year, but the years 1700, 1800 and 1900 were not. Got it?
