T'S THAT TIME again: Next Saturday, February 29, is a leap day, the calendar oddity that occurs (almost) every four years.
For centuries, attempts to sync calendars with the length of the natural year have sowed chaos—until the concept of leap year provided a way to make up for lost time.
"It all comes down to the fact that the number of Earth's revolutions about its own axis, or days, is not connected in any way to how long it takes for the Earth to get around the sun," says John Lowe, who led the National Institute of Standards and Technology (NIST)'s Time & Frequency Division until his retirement.
The solar year is approximately 365.2422 days long. No calendar comprised of whole days can match that number, and simply ignoring the seemingly small fraction creates a much bigger problem than one might suspect.
