FILE – NORAD Chief of Staff Maj. Gen. Charles D. Luckey takes a call while volunteering at the NORAD Tracks Santa center at Peterson Air Force Base in Colorado Springs, Colo., Dec. 24, 2014.

In the pre-digital age, the agency used a 60-by-80 foot plexiglass map of North America to track unidentified objects. A staff member jokingly drew Santa and his sleigh over the North Pole.

Fifty calls a day followed, he said. In the pre-digital age, the agency used a 60-by-80 foot (18-by-24 meter) plexiglass map of North America to track unidentified objects.

FILE – NORAD Chief of Staff Maj. Gen. Charles D. Luckey takes a call while volunteering at the NORAD Tracks Santa center at Peterson Air Force Base in Colorado Springs, Colo., Dec. 24, 2014.

In the pre-digital age, the agency used a 60-by-80 foot plexiglass map of North America to track unidentified objects. A staff member jokingly drew Santa and his sleigh over the North Pole.

In the pre-digital age, the agency used a 60-by-80 foot plexiglass map of North America to track unidentified objects. A staff member jokingly drew Santa and his sleigh over the North Pole.