Celebrity Leaplings

Self-help guru Tony Robbins was only six years old when he published his first book, "Unlimited Power." And rapper Ja Rule was only five when his debut album, "Venni Vetti Vecci," went platinum.

No, they weren't child prodigies -- these celebrities are "leaplings," people who were born on February 29, the extra day added during a leap year.

Of course, celebs like Tony Robbins and Ja Rule weren't really kids when they made it big. But since their birthdays appear on calendars only once every four years, you could be excused for considering a 26-year-old to be six or a 23-year-old to be five.

Leap years, leap days and leaplings owe their existence to the peculiar way we keep time and lay out our calendars. While we conventionally count a year as lasting 365 days, it actually takes our planet 365 days, six hours, nine minutes and 9.7 seconds to complete a single revolution in its orbit around the sun. Astronomers call that a sidereal year, and it's close enough to count as 365 and one quarter days.

In Pictures: Celebrity Leaplings

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So in order to get rid of that pesky quarter-day (and make the scientific facts reconcile with our regular calendar), we add a single day back onto the calendar every four years. So 2008 will last 366 days, not 365--and anyone born Feb. 29, 2008, will have to wait until 2012 for their next true birthday.

The Romans were the first to think up this clever little time trick. Before the founding of the Republic, ancient Romans based their calendar on both the phases of the moon and the solar year. That meant that most years lasted 12 months, and measured 355 days. In order to make up the difference, they'd occasionally have a 13-month, 377-day year. But when Julius Caesar introduced a new calendar--dubbed the Julian calendar -- in 46 B.C., he cleaned things up and moved to a 365-day calendar with one extra day every four years.

Usually, people born on a leap day simply choose to celebrate their birthdays on February 28 or March 1. But sometimes the missing day can lead to tragedy. In the famous Gilbert and Sullivan comic opera "The Pirates of Penzance," a main character is locked into a life-long apprenticeship with a pirate crew when he realizes his contract releases him on his 21st birthday -- and because he's a leapling, that won't come around until his eighties.

Famous leaplings throughout history include Pope Paul III, born in 1468; Italian composer Gioachino Rossini (1792); band leader Jimmy Dorsey (1904); French-Polish painter Balthus (1908); and songstress Dinah Shore (1916).

More recent leaplings include actor Dennis Farina, best known for playing the role of Detective Joe Fontana on "Law & Order" and for appearing in movies like "Midnight Run" and "Saving Private Ryan." Born in 1944, he's sixty-four years old this year -- but has only seen 16 birthdays.

Actor Alex Rocco is best known for playing Vegas mob boss Moe Green in "The Godfather." He was born on Feb. 29, 1936, making him either 72 or 18, depending on how you look at it.

National Hockey League goalie Cam Ward made history when he helped the Carolina Hurricanes win the Stanley Cup in 2006. He's now in the record books as the first rookie goalie to win the championship in over 20 years.

But wouldn't it be more impressive for this leapling to boast that he'd won the cup at the age of five?