Norad's Santa Tracker is an annual Christmas tradition that began back in December 1955, when a straight-laced military man decided to be a good sport in response to a newspaper typo that prompted kids to call his top-secret hotline.

As the story goes, Sears Roebuck & Co. had placed an advertisement in a Colorado Springs newspaper telling kids to call a phone number so they could talk to Santa.

However, the number was wrong.

Instead of Santa, the five-year-old child who called the number seeking the man in the red suit got Col. Harry Shoup, the operations commander at the Continental Air Defence Command in Colorado.

The hotline was meant for calls from generals, or even the U.S. president, so the colonel was taken aback and thought somebody was playing a trick on him.

Asked by the young voice on the line if he was one of Santa's helpers, the military man finally figured it was a child calling. 

Many more calls came in to that wrong number, leading the colonel to call a local radio station and say: "We have an unidentified flying object. Why, it looks like a sleigh!" Kids who called the military phone were given updates by Shoup's staff.

From that beginning, the Norad Santa Tracker operation now fields more than 100,000 phone calls that keep 1,200 volunteers busy on Christmas Eve. The Santa Tracker website gets more than 20 million visitors. 

Watch Reg Sherren's report above for more on the story of how Norad began tracking Santa's flight.

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