Norad Santa tracker follows Kris Kringle's sleigh as he delivers gifts around the world

Santa Claus is coming to town.

The jolly happy soul packed up his sleigh and started his route around the world around 1 a.m. ET Saturday, according to North American Aerospace Defense Command (Norad).

For the 61st time, Noradwasthe official Santa Tracker, and wasalso answering the calls and questions fromchildren around the world. The website followedSanta on hisroute and includeda few videos of Santa flying through cities around the world.

Norad, a joint Canada-U.S. operation based in Colorado,said it kept up with Santa's swift pace by using a system of "SantaCams" and satellites withheat-sensing infrared sensors that candetect heat signatures from Rudolph's nose "with no problem,"as the lead reindeer pulled the jolly old soul'ssleigh across the sky.

"The moment our radar tells us that Santa has lifted off, we begin to use the same satellites that we use in providing air warning of possible missile launches aimed at North America,"Norad said on the FAQ section of its Santa website.

For any kids planning to try tosneak a glimpse of Saint Nick, Noradsaid it's impossible to predict exactly when he'll arrive at your house.

"Only Santa knows his route," Norad said. "We do, however, know from history that it appears he arrives only when children are asleep! In most countries, it seems Santa arrives between 9:00 p.m. and midnight on December 24th."

The first stop for Santa was in Russia. By 9p.m.ET, Santa had already delivered over 4.5 billion gifts, startingin New Zealand and Australia, then navigating across much of Asia and into Europe.He is expected to arrive inNorth America later today.

Santa arrived in Canada at around 9:20 p.m. ET, escorted byRoyal Canadian Air Force CF-18s.

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"The responsibility of keeping watchful eyes over North American airspace 24/7 rests with our men and women of the Canadian Norad Region," said Maj.-Gen. Christian Drouin,commander of 1 Canadian Air Division/Canadian Norad Region, in a news release. "It is a duty and honour we hold dearly: to ensure Santa's safe passage through North America so he can deliver joy and goodwill this holiday season."

Curious kids can call Norad at 1-877-Hi-Norador email Noradtracksanta@outlook.com to find out where Santa is headed next.

You can also follow the Santa Tracker on Twitter, Facebookand YouTube.