As a leap year baby, I’m technically turning 10. But I’ve endured 40 years of bad jokes

Forty years ago, to the day, a heavily pregnant woman suffering in the late summer heat was more than ready for her baby to arrive. Despite being two weeks past her due date, the almost 10 pound baby was in no rush.

An induction was planned, but after seeing the date, the heavily pregnant mother was suddenly willing to wait one more day. The baby arrived into the world on February 29.

Samantha Allemann was born on the leap year day of February 29 and turns 40 (or 10) on Thursday.

I’ve always loved my birthday. For one thing, it’s given me something to say when I had to share an interesting fact about myself. It tends to stick in people’s minds, so I get a flurry of messages on my special day. It feels different, unusual. There’s only a one in 1461 chance of being born on February 29, making it the rarest birthday.

Yet, us leaplings are still not as unique as we feel. I have two other leapling friends, both unrelated to each other. We met at a leapling convention, where those of us born on February 29 eat canapes and make a bunch of small talk about our birthdate. Just kidding, we met at work.

Both are born four years before me, so they have endured four more years of the same old comments and cringey jokes – “how old are you really?” and “you’re pretty tall for a six-year-old”.

While they both claim March 1 as their birthdays on non-leap years, I’ve always felt loyalty to February 28, choosing it as my day to celebrate. March is a different month after all, and the start of a new season. And had I exited the womb on my due date I would have been a February baby, so it just feels right.

Unless, of course, March 1 falls on a preferable day of the week – say a Friday. Then, my loyalty to February 28 suddenly disappears because as common as it is for a leapling to be questioned on which day they celebrate, most people don’t strictly adhere to partying on their birthdate, and who in their right mind wants to host a party on a Tuesday?

The question that rarely gets asked is why we even have a February 29 every four years. Given I couldn’t offer anything more than a mumbled offer of “it’s to do with the earth … and the sun … the calendar”, I’m glad I haven’t been quizzed on it.

Fortunately, my fellow leaplings in the Honor Society of Leap Year Day Babies group on Facebook are more clued-up on the matter. “Mathematically, the earth makes one complete revolution around the sun about every 365 days – but not exactly, it’s closer to 365 1/4 days,” explains Becky, an amateur astronomer and member of the aforementioned society. “And it would be silly to try to have 1/4 of a day here on Earth, so we accumulate those one quarter days and add one whole day every four years (4 quarters equals 1 whole).”

There’s a pressure to celebrate and go all out on leap year birthdays. Credit: Stocksy

But it gets more complicated. As NASA explains in their school resources for 10-year-olds (perfect for me, given I technically turn 10 today), if the earth revolved around the sun in exactly 365 days and six hours, this system of adding a leap day every four years would be fine. “However, Earth takes a little less time than that to orbit the Sun,” writes NASA.

“Rounding up and inserting a 24-hour leap day every four years adds about 45 extra minutes to every four-year leap cycle. That adds up to about three days every 400 years.” In other words, it turns out that years that are divisible by 100 don’t have leap days unless they’re also divisible by 400.

That’s too much math for me to grasp, but the good news is that I won’t have to worry about it anyway because the next instance of this will be in 2100.

As to why February 29 was chosen as the additional day, us leaplings can thank the Romans for that. February was the last month of the year in the original Roman calendar, but then Julius Caesar added some extra days into the mix to bring the total number of days in a calendar year closer to the solar year. Thus, February, the shortest month, was allocated an extra day.

The years in which February 29 rolls around have always felt more exciting to me, with more pressure to mark the day in a big way. The temptation is to go all out, to grasp that fleeting day with all my might, given it’ll be another four years since it returns. But this year, I’m keeping things low-key, focusing on feeling grateful for another trip around the sun.

Today, a whole new cohort of leaplings will enter the world. As they grow, may they be healthy, happy, and better able to explain the earth’s rotations if anyone asks them.

Samantha Alleman is a Melbourne writer.

The Opinion newsletter is a weekly wrap of views that will challenge, champion and inform your own. Sign up here.