NORAD has been following Santa's movements from space since 1955, when an advert encouraging children to phone Santa gave out its number instead.
Colonel Harry Shoup ordered staff to answer calls with an update on Father Christmas' location and the tradition has continued, now with a live tracker of Santa's journey online.
It shows his path above different countries and has a counter that reveals the number of presents delivered.
Volunteers are manning NORAD's 157 phone lines and computers at Peterson Air Force Base in Colorado Springs to field hundreds of phone calls, emails and tweets from anxious children, wondering what time Santa will arrive.
International aircraft have even been warned to steer clear of the North Pole as Santa Claus dashes around the world at almost the speed of light. Kris Kringle is currently over Tonga, according to NORAD's tracker
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