AUDIE CORNISH, HOST:
Four hundred and 30 years ago, Pope Gregory XIII gave the West a calendar, which divided 365 days into what was to be called a year. With 12 months and seven days bundled into so-called weeks, the Gregorian calendar was hailed as a marvel of medieval accuracy. We use it today, despite its occasional messiness - drifting days, leap years and 28-day months. But now some researchers at Johns Hopkins University have devised a different way to count our days with a leap week every few years to keep the calendar on track. Holidays, like Christmas and New Year's Day, would always fall on a Sunday. It seems neat and streamlined for our modern age, except maybe to those of us who work on Sundays.
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