It was December 1955, the height of the Cold War, when the red phone on Col. Harry Shoup’s desk at the Continental Air Defense Command began to ring.

Shoup reached for the phone.

“Yes, sir. This is Col. Shoup,” he said.

No response.

“Sir? This is Col. Shoup.” Pause. “Sir, can you read me all right?” That’s when Shoup heard the little girl’s voice.

“Are you really Santa Claus?”

For the last 60 years, officials at the North American Aerospace Defense Command at Peterson Air Force Base in Colorado Springs, Colo., have tracked Santa’s whirlwind tour across the globe to deliver presents on Christmas Eve. Nearly 9 million people from more than 200 countries are expected to check in with NORAD’s Santa-tracking website before they go to bed on Christmas Eve.

So Shoup told the little girl on the other end of the line that he was, indeed, Santa Claus. Then Shoup asked to speak to her mother. That’s how he learned that a Sears, Roebuck & Co. advertisement in the local newspaper had invited kids to call Santa at ME 2-6681 – the number for the red phone.

It was a misprint, of course, but that didn’t stop kids from flooding the line all the way until Christmas. After a few weeks, someone at the Continental Air Defense Command (which is now NORAD) had an inspired idea. He went to the giant glass board where airmen tracked the planes in U.S. or Canadian airspace and added a drawing of a sleigh with eight reindeer. They were headed south from the North Pole.

Shoup then he picked up his phone, his other daughter, Terri Van Keuren, told StoryCorps.

“He called a local radio station and said, ‘This is the commander of the Combat Alert Center, and we have an unidentified flying object – why, it looks like a sleigh!’ “

After that, Van Keuren added, stations would call every hour to ask for Santa’s whereabouts.

Today, more than 70,000 children still call NORAD to talk to Santa on a toll-free line.

Some 60 years ago, that first caller had a probing question. Before handing the phone to her mother, she asked forthrightly: How is it possible for Santa to visit so many houses in a single night?

Shoup, to his everlasting credit, had the perfect answer. “I said, ‘That’s the magic of Christmas.’ “