What would happen without a Leap year? More than you might think

Leap year. It's a delight for the calendar and math nerds among us. So how did it all begin and why?

Have a look at some of the numbers, history and lore behind the (not quite) every-four-year phenomenon that adds a 29th day to February.

BY THE NUMBERS

The math is mind-boggling in a layperson sort of way and down to fractions of days and minutes. There's even a leap second occasionally, but there's no hullabaloo when that happens.

The thing to know is that leap year exists, in large part, to keep the months in sync with annual events, including equinoxes and solstices, according to the Jet Propulsion Laboratory at the California Institute of Technology.

It's a correction to counter the fact that 's orbit