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It's that time of year when people gather together to stay up late, make toasts, profess their well-intentioned resolutions for the next dozen months, and welcome in the New Year.

Of course, exactly when you and your friends celebrate the changing of the year is determined by precisely where you live. Which might lead you to wonder: How many different New Year's Eve countdowns are there around the world?

To answer this question, today we're going to celebrate the new year Math Dude-style by talking about the astronomical origin of time zones, their quirkiness, and some math fun facts about the changing of the year that you can share with your friends while you're waiting for midnight!

What Are Time Zones?
As you no doubt know, the time in New York is not the same as the time in Los Angeles. And the times in Tokyo, Beijing, Moscow, Baghdad, and London are all different, too. Of course, the reason is that each of these cities is located in a different time zone. And, most importantly for today, the time zone of each determines when it celebrates the new year.

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