Leap Day: What it means and what would happen without it

Leap year. It’s a delight for the calendar and math nerds among us. So how did it all begin and why? Ancient civilizations had calendars that made periodic corrections to realign with lunar and solar cycles. But it was Julius Caesar who put into practice what we now consider leap years back in 46 BC. In large part, the idea was to keep the months in sync with annual events, including equinoxes and solstices. Pope Gregory XIII in the late 16th century calibrated further. His Gregorian calendar remains in use today. He wanted to make sure the time for Easter didn't drift on the calendar.