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# New Year's Math Fun Facts

How many different New Year's Eve countdowns are there around the world? When do astronauts celebrate New Year's? Who celebrates first? And last? Keep on reading to learn all about these New Year's math fun facts.

By
Jason Marshall, PhD
Episode #180

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.

But where do time zones come from in the first place? The idea is simple: Imagine you walk outside at precisely noon and notice that the Sun has just reached its highest point for the day. Being so excited by this, you call your friend who happens to live in another city that's exactly 1/24 the circumference of the Earth to your west.

Your friend notes that the Sun has yet to reach its highest point where she lives, so you decide to stay on the line and wait until that magical moment arrives. Lo and behold, exactly 1 hour later, your friend determines that the Sun has peaked in the sky. Which, you both decide, makes perfect sense since there are 24 hours in the day and she lives 1/24 x 24 hours = 1 hour away.

While we might think that this is all pretty obvious, long ago it definitely was not. People had to come to grips with the fact that the Earth is round, that it's progressively and periodically illuminated by the Sun in an east-to-west manner (due to Earth's rotation), and so on.

Eventually people realized all of this and figured out that it'd be smart to divide the Earth up into 24 one-hour time zones so that morning would be morning, afternoon would be afternoon, and evening would be evening no matter where you live. Which, I think you'll agree, is a good thing!

## How many New Year's countdowns are there?

Although I said that people decided it'd be smart to divide the Earth into 24 evenly spaced one-hour time zones, that's not actually what happened. If you take a look at a map of the various time zones, you'll see that they're anything but even. That original idea of using nice straight north-south cuts around the Earth (the so called lines of longitude) for time zones went out the window as soon as politics got involved.

And that's not necessarily a bad thing. For example, many countries decided they didn't want to be split in half (or thirds, or more), and therefore chose to "bend" the time zone around their border. Others decided they'd rather be on one time zone or another (instead of the one they naturally fall into) in to order to remain economically competitive with a neighbor.

The end result is the quirky mish-mash of time zones that we have today. It's a mish-mash that has some expansive countries like China—which naturally spans 5 time zones—using only a single time zone, and other countries like the U.S. and Russia spanning more than a half-dozen time zones each.

That means there are 40 different countdowns to the new year! Starting with Kirimati/Christmas Island in the middle of the Pacific Ocean (which is 22 hours ahead of where I live in Los Angeles) and ending with American Somoa and a few other Pacific islands 25 hours later, New Year's celebrations go on for a long time.

## What time is it in space?

Now that we've got all of those details about what time zones are, where they come from, and how they affect New Year's celebrations out of the way, it's time for my favorite time zone fun fact: What time is it in space?

By which I mean, if you were an astronaut on the International Space Station (aka, ISS), how would you set your watch? After all, astronauts aboard the ISS witness sunrises and sunsets about every 90 minutes—which means they zoom through each 1 hour time zone in less than 4 minutes!

In truth, any time zone could have been chosen as the standard for spaceflight, but the most logical choice is what's called UTC (originally known as GMT)—which is the time at the Royal Observatory in Greenwich, England.

While UTC might seem like a rather random choice, it's really not. The Royal Observatory has been the center of the universe when it comes to time-keeping (and thus time zones) for centuries, and is therefore a natural choice for a universal reference—even in space!

## Wrap up

Okay, that's all the math we have time for today (and this year!).

Please be sure to check out my book The Math Dude’s Quick and Dirty Guide to Algebra.  Happy holidays and thanks for reading, math fans!