11 historic events that happened on February 29, also known as 'Leap Day'

On Leap Day in 1692, three women — Sarah Good, Sarah Osborne, and Tituba — were accused of witchcraft, marking the beginning of the Salem Witch Trials.

The fate of the women was bleak. Good was hanged for refusing to confess, Osborne died one year later in prison, and Tibuta, a slave, admitted to her alleged crimes and was eventually released from prison.

Ann Lee joined the Shaker movement, a pacifist sect of Christianity, in 1758. After having a "divine realization" 12 years later, she became the leader of the religious movement in Europe.

In 1774 she received another divine message telling her to establish a Shaker church in America. Two years later, she had gathered a following in Albany, New York.

On Leap Day in 1908, Heike Kamerlingh Onnes made an announcement proclaiming that "solid helium" was observed in his laboratory. But the Dutch scientist was slightly mistaken.

Onnes, known for his groundbreaking work in liquifying helium, had been experimenting with temperature and tried to condense the gas into glass tubes. During this process, the helium appeared to solidify.

Aghast by this discovery, Onnes was quick to announce his findings the very next day. But his observations were off, and weeks later it was realized that this phenomenon occurred only because of the presence of hydrogen.

Ivan Pavlov became known worldwide for his psychological study of "conditioning," or training someone to behave through a learned reflex.

The researcher is held in high regard. In 1904, he received a Nobel Prize in physiology/medicine for his research on digestion.

Hattie McDaniel won Best Supporting Actress for her role as Mammy in "Gone with the Wind."

In 1964, Princess Alexandra of Kent gave birth to a son, James Ogilvy, on Leap Day. The baby is believed to be the first royal baby in history born on February 29.

In 1972, Hank Aaron signed a three-year contract with the Atlanta Braves for about $200,000 a year, making him the highest-paid player in the league.

Buddy Holly's famous black glasses were rediscovered by a police officer on Leap Day over two decades after the singer died in a plane crash near Clear Lake, Iowa, in 1959.

The thick-rimmed glasses had been buried in the wreckage and turned into the County Sheriff's office a year after the crash. At that time, they were put into an envelope and completely forgotten about, until February 29, 1980, when County Sheriff Jerry Allen came across the frames and returned them safely to Holly's wife.

After nearly four years of continuous attacks by Serbs, the siege of the Bosnian capital Sarajevo was finally declared over on Leap Day in 1996. This event marked the longest siege in the history of modern warfare.

Davy Jones was born in Manchester, England, in 1945 and gained widespread recognition as the lead singer of the pop-rock group, "The Monkees."

Throughout his career, Jones was nominated for four Grammy awards, and even stared in acting roles for series such as "The Brady Bunch."

Jones died on Leap Day in 2012 from a sudden heart attack.