Mathematician Thomas Fernsler says, "I know more than probably anybody really wants to know about [the number 13]." For instance, a year, like 2009, with a triple set of Fridays falling on the 13th typically only comes around every 11 years. Also, the 13th day of the month is more likely to fall on a Friday than any other day of the week.
Those who share the phobia about 13 have a connection with some prominent historical figures. Napoleon, Herbert Hoover and Franklin D. Roosevelt all feared it. Fernsler thinks this is normal: "If you're not superstitious, maybe you should be. 87% of all the people in the world are superstitious about something. The other 13% are liars."
Here are some reasons why: The first person to die in a car accident was killed in New York City on Sept. 13, 1899.
The British Navy built a ship named Friday the 13th. On its maiden voyage the vessel left dock on a Friday the 13th, and was never heard from again.
The ill-fated Apollo 13 launched at 13:13 CST on 4/11/70.
The sum of the date’s digits is 13. The explosion that crippled the spacecraft occurred on April 13th.
Quarterback Dan Marino wore No. 13 throughout his career with the Miami Dolphins. Marino is said to be the best quarterback who never won a Super Bowl.
Butch Cassidy was born on Friday, April 13, 1866. Fidel Castro was born on Friday, August 13, 1926.