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Everything you need to know about leap years

This year, there won’t be 365 days as normal, there will be 366. With the extra day tacked on to the end of our shortest month: February. That’s right, 2020 is a leap year. The year every “leaper” (anyone born on the 29th Feb) gets to celebrate their real birthday. Hooray!

But why do we have this extra day that lies in wait for four years before popping up again? Who came up with the idea? And what does it have to do with a tiny town in Texas? Here is everything you need to know about leap years.

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1. Leap years are all because of the sun

It takes 365 ¼ days for the earth to rotate around the sun. But the calendar year is 365 days. So, to synchronize the calendar year with the solar year, we add an extra day every four years. If we didn't have leap years, our calendar would gradually fall out of line with the seasons.

If we didn't have leap years, our calendar would gradually fall out of line with the seasons.

2. Every 100 years, we skip a leap year. (Almost.)

OK, so we’ve said it takes 365 ¼ days for the earth to rotate around the sun but, in actual fact, it takes 365 days, 5 hours, 48 minutes and 46 seconds. Eventually even this small discrepancy would knock our calendar off course. So, leap years occur every four years, but every 100 years we skip a leap year – unless the year is divisible by 400. Confused? For example, the years 1700, 1800, and 1900 are not leap years, but the years 1600 and 2000 are.

3. It’s called a “leap” year because it’s all about leaping ahead

We use the phrase leap year because each date on the calendar jumps ahead two days of the week instead of one. If your birthday fell on a Sunday last year, this year it will leap over Monday and land on a Tuesday. So, no Monday birthday this time around. Lucky you!

4. Non leap years have a name too

A year that is not a leap year is called a common year. Because it’s, well, more common.

5. Leap years were the brainchild of Julius Caesar

Across time, humans have had to come up with strategies to keep their calendar in line with the seasons. Some cultures got around the problem by throwing in an extra month or week when the need arose. It was the Roman Emperor Julius Caesar who, in 46 B.C., had the canny idea of adding an extra day every fourth year.

6. The odds of being born on a leap day are one in 1,461

The 29th February occurs every four years, or 1,461 days. Therefore, the chances of being born on that day, and earning the title of “leaper” or “leapling”, is just one in 1,461.

7. This year, 29th February falls on a Saturday

The good news is, this year’s extra day falls on a Saturday. Bonus! This is extra exciting when you consider the 29th February falls on a Saturday only once every 28 years (except when a year evenly divisible by 100 is not a leap year, like 2100).

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8. If you have a fixed annual salary, a leap year means you’re working an extra day for free!

The bad news is, if we earn an annual salary, we likely don’t get paid any extra for a leap year. Therefore, technically, anyone who is at work that day is working for free!

9. Traditionally, 29th February is the day woman propose to men

It’s not quite clear where or when the tradition started, but one theory suggests that it was Queen Margaret of Scotland who, in 1288, aged just five, introduced a law allowing women to propose to men on the 29th February. Said women had to wear a red petticoat to make their intentions known. And any man who refused a marriage proposal would be fined a kiss, a silk dress or twelve pairs of gloves! Thankfully, times have changed. You can get down on one knee any day you like.

10. Anthony, Texas is the Leap Year Capital of the World

In 1988, Anthony resident and leap year baby Mary Ann Brown approached the Chamber of Commerce with the idea of the town holding a leap year festival. It was agreed, and Anthony was declared the Leap Year Capital of the World. Ever since, “leapers” from across the globe have travelled to the Texan town to take part in parades, birthday dinners, square dancing and hot air balloon rides.

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