Terri Van Keuren, Rick Shope and Pam Farrell, who talked with StoryCorps about their father, Air Force Colonel Harry Shope.

(StoryCorps)

On Christmas Eve, people all over the world will log on to NORAD's official Santa Tracker to follow his progress on U.S. military radar. The tradition is in its 60th year, and it started because of a misprint in a Colorado Springs newspaper that led to a call to Air Force Colonel Harry Shope.

Shope was manning the secret hotline at the Continental Air Defense Command, now known as NORAD, when, according to Shope's children, the phone rang and a young voice asked, "Is this Santa Claus?" After initially wondering if it was a prank, Shope realized it wasn't, and responded as if he was Santa. And with that, the tracker was born. Here's what it looks like this year:

Shope's children, Terri Van Keuren, Rick Shope and Pam Farrell, recounted the tale to StoryCorps. The segment originally aired on NPR's Morning Edition on Dec. 20, 2014.