Why do we leap day? We remind you (so you can forget for another 4 years)
MICHEL MARTIN, HOST:
We get an extra day this month. Yay. 2024 is a leap year, which means February has 29 days.
STEVE INSKEEP, HOST:
Woo.
MARTIN: This morning, we investigate why.
JACKIE FAHERTY: So the leap year is a really fascinating astronomical phenomenon, if you can call it that.
INSKEEP: Jackie Faherty is an astronomer at the American Museum of Natural History in New York. And she does call it that because she's got the math. Most years last 365 days. But it takes the Earth just a little longer to go around the sun 365 days, six hours and nine minutes.
FAHERTY: And that .242190 days extra to go around the sun is the entire reason why we have a leap year.
INSKEEP: It's an extra quarter of a day, so we add a every four years, without which, the calendar would gradually get out of sync with the planet.
FAHERTY: Nothing physically happens. Like, you're still going to have winter when winter happens and summer when summer happens. But the month that you call it is going to be different.
MARTIN: If we went many years without leap days, summer would arrive in November.
FAHERTY: This is as much a history lesson as it is anything else, because it's the history of how we started using calendars and how we started needing to keep track of time, because from an astronomical point of view, nothing is happening. So the leap year is a correction on an imperfect calendar, frankly.
INSKEEP: Alexander Boxer wrote the book "A Scheme Of Heaven."
ALEXANDER BOXER: Our calendar, the one that we use every day, is this amazing product of multiple civilizations, each building on the other over thousands of years and sharing in this great undertaking of trying to understand time, which, you know, is, on the one hand, both aspirational but also a very human compromise.
MARTIN: We have in-depth coverage of that compromise all week. We only get this chance every four years, so tomorrow, we report on birthday celebrations that come February 29.
INSKEEP: Birthdays that keep you young.
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