# Leap Year 2024: Why February 29, what is it and why it occurs once every 4 years

If your birthday is Feb. 29, it's been a long four years. The good news is, the countdown's on to Leap Year 2024.

Once every four years, an extra day is added to the month of February. That year is considered a Leap Year, and Feb. 29 is known as a Leap Day. Here's what to know about the "holiday" (we used quote marks because it's not an official holiday, but there are deals and lots of hoopla that surround this special day).

## When is Leap Day 2024?

Leap Day is Thursday, Feb. 29, 2024.

## Why does Leap Day occur once every four years?

Our calendar is not entirely in sync with our planet's trip around the sun.

According to NASA, while there are 365 days in one year, it takes our planet about 365.25 days to make the full circle around the sun. Roman emperor Julius Caesar decided to compensate for that so it didn't become a growing problem as time went on. He did so by adjusting the calendar to include an extra day every four years. That plan was later tweaked by Pope Gregory XIII, who added Leap Days should not occur in years ending in 00 unless divisible by 400.

Every four years, we have 366 days on the calendar instead of our usual 365. If we didn't observe leap years, our seasons would be messed up as our equinoxes and summer and winter solstice would no longer align with the seasons.

"If there were no leap years, the seasons would completely swap every 750 years, i.e. the middle of summer would become the middle of winter − calendar climate change," astronomy expert Dr. Stephen Hughes of Queensland University of Technology said in a Feb. 29, 2012 (a Leap Year) article on AsianScientist.com.

## How long does it take Earth to orbit the sun?

It takes Earth 365 days, 5 hours, 48 minutes and 45 seconds to orbit the sun. That's almost an extra quarter of a day per year. If you round the quarter up for each year, you get an extra day added every fourth year.

## What would happen if we didn't observe Leap Year? What if we got rid of Leap Day?

If we didn't use Leap Years, our calendars would be off by 25 days after 100 years. It's not a perfect system − Leap Years are skipped on century years that are evenly divided by 100, like 1900 and 2100. Leap Years are not skipped on century years that are evenly divided by 400 such as 2000 and 2400.

The year must be evenly divisible by 4. If the year can be evenly divided by 100, it is not a Leap Year unless the year is also evenly divisible by 400, according to mathisfun.com. For example, 2000 and 2400 are leap years, but 1800, 1900, 2100, 2200, 2300 and 2500 are not.

## If your birthday is on Feb. 29, which day do you use to celebrate? What date do you use for official documents or ID?

Those born on that day don't always get to celebrate their actual birthday — since that date occurs only every four years. Someone born on Leap Day typically celebrates birthdays on Feb. 28 or March 1. But Feb. 29 is still used for identification and important documents.

## Is there a 'Leap Year marriage proposal' superstition?

Thanks to Amy Adams, Adam Scott and Matthew Goode, Leap Year and marriage proposals in Ireland became part of the Hollywood romantic comedy genre. The movie focused on the premise that women can only ask men to marry them one day every four years in Ireland.

Adams, best known for Disney's "Enchanted" films and several Academy Award-nominated roles, played "Anna from Boston" in "Leap Year." Her character follows her boyfriend, Adam Scott ("Parks and Recreation" and "The Secret Life of Walter Mitty"), to Ireland so she can propose to him on Leap Day, a supposed good luck charm for a long and happy marriage. Matthew Goode ("The Imitation Game" and "A Single Man") escorts Anna to Ireland amid a series of mishaps.

The 2010 movie inspired Leap Day promotions. In 2020, a hotel in Iceland (not Ireland) offered a free stay to women who proposed marriage there. Buzz60 reported: Hotel Ranga offered a "take the leap" promotion, which included a free one-night stay on Leap Day for a woman and her partner who she wants to propose to. It included chocolate-covered strawberries, a bottle of Champagne and breakfast.

Hotel Ranga includes a stargazing room and an amazing view of the Northern Lights.

According to Buzz60, the hotel's marketing manager told Travel and Leisure in 2020 that "Iceland in general is a big champion of of women, and we love that leap year has this tradition where it's good luck for ladies to propose marriage on this day."

## Countdown clock to Leap Year 2024. How many days until Leap Day?

Contributing: USA TODAY

Sangalang is a lead digital producer for USA TODAY Network-Florida. Follow her on Twitter or Instagram at @byjensangalang. Support local journalism. Consider subscribing to a Florida newspaper.

This article originally appeared on Florida Today: Leap Day: What happens if Feb. 29 is your birthday, when to celebrate