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​Milepost: Leap Year Day

On February 29th we celebrate that quadrennial anomaly known as Leap Year Day
Happy Leap Year Day 01:19

Tomorrow, February 29th, we celebrate that quadrennial anomaly known as Leap Year Day.

Blame it on the Earth's awkwardly-paced journey around the sun. It takes roughly 365-and-a-quarter days for our planet to complete the loop.

The ancient Roman calendar tried to fix the problem by adding a Leap Year Day every four years ... close, but slightly too often.

By 1582, the Roman calendar was 24 days out of sync with the seasons, which is where Pope Gregory XIII comes in.

That year he decreed a new calendar (called the Gregorian calendar, naturally), which eliminated Leap Year Days in any century year not divisible by 400.

For example, in 1900 there was no Leap Year Day. But in the year 2000, as you may remember, there WAS.

None of which resolves the nagging question: when DOES a Leap Year Day baby celebrate his or her birth in a NON-Leap Year ... on February 28th, or March 1st?

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