What began as a misprint in a newspaper ad has become a Christmas tradition celebrating its 66th year of operation.

The rest of the year, NORAD is known as the organization whose job it is to watch the skies over the United States to make sure no airborne intruders make their way into our airspace.

But, every Christmas Eve since 1955, these eyes on the skies turn their attention to the North Pole, tracking the annual trek around the world of Santa Claus, along with his sleigh and eight tiny reindeer.

And it all began with a mistake in a newspaper ad.

In a 2014 article on npr.org, the children of Colonel Harry Shoup told the story of the day in December, 1955 that "The Red Phone" rang in the offices of what was then the Continental Air Defense Command in Colorado Springs, Colorado.

Col. Shoup answered the phone, expecting to perhaps hear of an attack on the United States. Instead, it was a small boy asking, "Is this Santa Claus?"

It turned out there had been ad printed in the local newspaper, giving a number for kids to call and talk to Santa. There was a typo in the ad, so the number listed was the Hot Line phone of the Air Defense Command.

Fortunately, Col. Shoup was a good sport about the situation. When Christmas Eve came, one of Shoup's men kiddingly suggested they should track Santa. Shoup immediately got on the phone to the local radio station, talking about tracking an unidentified flying object that looked strangely like a sleigh.

And the rest, as they say, is history.

If you'd like to use the NORAD Santa Tracker on Christmas Eve, you can go to noradsanta.org, call 877-HI-NORAD, or, of course, you can download the NORAD Santa Tracker on your smart phone.

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