WASHINGTON (AP) -- The North American Aerospace Defense Command, or NORAD, has been tracking Santa Claus' annual Christmas Eve journey to deliver presents to good boys and girls for decades.

This year marks the 61st anniversary of the effort, and "we have about 1,500 people who volunteer their time" to keep children informed about the jolly old elf's progress as he circles the globe, said United States Army Maj. Jennifer Stadnyk of NORAD.

The same high-tech equipment used to detect and issue warnings about attacks on North America from aircraft, missiles and space vehicles allows NORAD, which is based in Colorado, to keep up with what Santa is doing.

"We have 47 radar installations in Northern Canada and Alaska, and they alert us when Santa actually leaves the North Pole," Stadnyk said. "We also have satellites at about 22,000 miles above the Earth. They have infrared sensors, so they can see the heat coming off of Rudolph's nose. In addition, we have high-speed digital SantaCams that we set up around the world so we can catch a glimpse of him passing by the different cities."

When Santa arrives in North America, Canadian NORAD fighter pilots, flying CF-18s and their American counterparts, flying F-15s, F-16s or F-22s, escort him while he makes his rounds.

"I have helped track Santa for the last four years," Stadnyk said. "Most of the time, children want to know when Santa will get to their house, and sometimes they ask if we can see, with our satellites, if what they asked for is on his sleigh. What we often tell the kids is that Santa won't stop at their house until after they are asleep, and letting them know that makes them want to get to bed faster."

In any given part of the world, Santa usually makes his deliveries to homes between 9 and 11 p.m., local time.

"If the children are still awake, Santa will skip their house, but he will go back once they've gone to bed," Stadnyk said.

There are a number of ways to find out where Santa is on Christmas Eve. They include the NORAD Tracks Santa website, www.noradsanta.org, and NORAD Tracks Santa apps, which are available in the Windows, Apple and Google Play stores.

Starting at 6 a.m. EST, youngsters interested in Santa's trip can speak with live phone operators by calling 1-877-Hi-NORAD (1-877-446-6723) or they can send an email to noradtrackssanta@outlook.com.

At any time on Dec. 24, Windows Phone users can ask Cortana for Santa's location and OnStar subscribers can press the OnStar buttons in their vehicles to get the same information.

"Our website got about 22 million visits, and we answered 140,883 phone calls and about 2,800 emails," Stadnyk said. "We have more than 1.6 million followers on Facebook and around 163,000 followers on Twitter."

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