Leap day

Happy Leap Day! It's not often we get a February 29, so to celebrate this day that comes only once every four years (roughly), I researched some questions I've had about leap years, and I wanted to share what I found with all of you.

1. Why do we have leap years?
This one is easy, and you probably already know the answer. The Earth takes more than 365 days to orbit the sun. To be more precise, rounding to three decimal places, it takes 365.242 days for our planet to circle the sun. If we didn't have leap years, our calendars will eventually go out of sync with the seasons.

2. What's the rule for determining if a year is a leap year?
In most cases, years that are divisible by 4 are leap years, e.g., 2020. The exceptions are century years, which have to be divisible by 400, e.g., 1600, 2000, 2400. The reason that not every century year is a leap year is because it doesn't quite take 365 1/4 days for the Earth to complete its orbit. If we had leap years every four years, we'd wind up with too many.

3. How often do people who are born on Feb 29 celebrate their birthdays?
I've wondered about this for a long time. If you're born on Feb, do you get a birthday party only once every four years? Apparently, people who are born on leap day celebrate their birthdays on Feb 28 or Mar 1. If you happen to be born on Feb 29, I'd love to hear about when/how you celebrate your birthday!

4. Any other interesting leap year trivia?
I'm sure there are lots that you can find by searching the internet. I found this fact pretty astonishing though. According to Guinness World Records, the Keogh family of the UK has three generations of family members with birthdays on Feb 29. Peter Anthony Keogh (Feb 29, 1940), son Peter Eric Keogh (Feb  29, 1964), and granddaughter Bethany (Feb 29, 1996) all share the same birthday. I wonder what those birthday parties are like!