Every four years is a leap year, when we add an extra day to the year. 2020 is a leap year, so today, for the first time in four years we have a 29 February.
So why do we have an extra day in the year, every four years?
Every non-leap year actually lasts 365.25 days – the time it takes the Earth to orbit the sun once. i.e. It takes a quarter of a day more each years than the standard 365 days we have in a year.
If we didn’t add on an extra day every four years our calendar year would be off by one day after four years. And after 100years, it would be off by 100 years. Eventually if we didn’t correct this quarter day difference we get every year, February would eventually end up being a month in the middle of summer in the Northern Hemisphere.
So that’s the background on why we only have a 29 February every four years. But one thing has always intrigued me about the 29 February, and that, when do people who were born on a 29 February, celebrate their birthday, in non-leap years!
I’m sure they might like to just be ‘a year older’ every four years, but I’m equally sure they celebrate their birthday each year. However what I’ve often wondered is when they celebrate – Do they celebrate on 28 February or wait until 1 March, or do they acknowledge their birthday every year, but only celebrate it in a leap year. So if you were born on 29 February, or know someone who was, I’d be interested to hear when you/they celebrate your/their birthday.