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The Science Behind: Time Zones (Cover- Sara Chaudhari)

As I type this it is 4:55 PM in California, 7:55 PM in New York, 12:55 AM in London, and 9:26 AM in Adelaide.

Isn't it weird that in some parts of the world, humans are getting up and on the other side people are falling asleep? On one end of the world, it is still May 18th and in other parts its either May 17th or May 19th!

That's the concept of time zones...

We all know that the Earth is a sphere that rotates on an axis. A full turn takes 24 hours which is what we call a day. As the Earth rotates different parts see the sun. When your part of the world has had its turn with the sunlight you see the sunset.

All the time zones are measured from the Greenwich Observatory in England. This point became known as Greenwich Meridian or the Prime Meridian. Time at this location is known as Greenwich Mean Time (GMT) or Universal Time.

But why Greenwich? What's wrong with other places in the world? Why is it not in Manchester or Bradford?

In 1884, The Greenwich Observatory was declared as the Prime Meridian. Although in the 1950s the observatory was moved to Sussex, Greenwich is still the prime location.

What about before 1884?

People always knew about time time zones, but they weren’t always organized. One person would make sure that the town clock read noon when the sun was highest, running around town adjusting everyone’s clocks.

As the world grew more and more advanced, people grew more and more unorganized, at open point there were 75 different time in the US.

In the late 1800’s a group of scientists finally figured out how to organize time.

The idea is to divide the Earth into twenty-four fifteen degree slices and set the clocks according to each piece. Everyone who lives in the same part sets their clock the same way.

However, some nations decided to do their own thing. For example, in China, no matter where you go in the country, the time is the same, even though traditionally China spreads over three different time zones.

Most countries, still go by the classic GMT, but how does it work?

Let’s imagine you’re in good ol’ North Carolina. Charlotte, North Carolina is 5 time zones west of Greenwich. This would written as GMT-5. And let’s imagine your best friend lives in Madrid, Spain. Spain is 1 unit east of Greenwich, this would be notated as GMT+1. This means that you and your best friend are six mile zones apart. So if its six in the morning for you, its noon in Madrid. If it’s six in the evening for you, it would be midnight in Spain.

So wherever you are in the world today, I hope you enjoyed this article. Even if you’re reading this as six in the morning or at midnight under your blanket. Or if you’re reading this while eating lunch or getting ready for bed. I hope you learned something!

Until next time...

Stay Curious ;)




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