Maybe you know someone who lives far away and is a few hours ahead of you. How is that possible? Is it time travel? Of course not! They just live in a different time zone. To understand time zones, start by thinking about the shape of the Earth.
You know our planet is a sphere that spins on an imaginary pole called its axis. Every 24 hours, the Earth makes a complete rotation.
We call each full turn a day. Imagine shining a flashlight at a globe. Only part of it would receive light. The opposite side would be dark.
As Earth rotates, different parts of Earth receive sunlight or darkness, giving us day and night. As your location on Earth rotates into sunlight, you see the sun rise. When your location rotates out of sunlight, you see the sun set. Imagine if the entire Earth had a single time zone. Noon would be the middle of the day in some places, but it would be morning, evening, and the middle of the night in others. Since different parts of Earth enter and exit daylight at different times, we need different time zones.
Just over a century ago, towns and cities set their own time. One person would make sure the official town clock read noon when the sun was highest in the sky each day. As the world became more connected, this grew complicated. Especially as people began to travel across North America by train , the many time zones became difficult to follow.
At one point, train stations in the United States alone had to keep up with 75 time zones across the country. In the late s, a group of scientists came up with a new system for time zones. They called it standard time. As Earth rotates on its axis , it moves about 15 degrees every 60 minutes.
After 24 hours, it has completed a full rotation of degrees. The scientists used this information to divide the planet into 24 sections or time zones. Each time zone is 15 degrees of longitude wide. Distance between the zones is greatest at the equator. It shrinks to zero at the poles because of the curvature of Earth. Since the equator is about 24, miles long, the distance between time zones at the equator is approximately 1, miles.
The imaginary dividing lines begin at Greenwich, a suburb of London. The primary dividing line of longitude is called the prime meridian. Longitude is the angular distance between a point on any meridian and the prime meridian at Greenwich. As you move west from Greenwich, every degree section or time zone is an hour earlier than GMT, while each time zone to the east is an hour later.
Not everyone accepted the idea of standard time right away. In fact, many countries continue to set their own times today. Other nations adopted systems that change time zones by smaller increments, like 15 or 30 minutes.
For that reason, there are more time zones than the standard 24 in use today. Having different time zones means that no matter where you live on the planet, your noon is the middle of the day when the sun is highest, while midnight is the middle of the night.
Charlotte is five time zones to the west of Greenwich, which is written as GMT This means Charlotte and Madrid are six time zones apart. When your cousin is eating lunch at noon Madrid time, you are probably just getting out of bed to get ready for school. This is because at p. On the other hand, if you wanted to chat with your cousin online after dinner at p. Time zones are further complicated by Daylight Savings Time , which is observed by some countries and not others.
Have you ever been surprised by a time change? Are you ready to time travel? Find a friend or family member to help you check out the following activities:.
Hi Marvin! Thanks for being so kind in your communication. If cars drive flat and not curved then the world is flat!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Hi, Makenna! It may seem like that, but the world is round! Wonder Why Is Earth Round? Thanks for asking, Michale! We ask that Wonderopolis be listed as the author. Also, since we do not list the publish date for our Wonders of the Day, you may put the date you accessed this page for information. The following is how you would cite this page:.
Accessed 25 Apr. Hi, Science wonder! We hope that reading through this Wonder will help answer your questions about time zones! You're asking some great questions, 11! We have one for you: are you ok in the Upside Down? Thank you! There is absolutely no reason to have time zones. It just makes it confusing to figure out what time it is somewhere else. Who cares where the sun is at noon?
Just imagine how easy life would be without them. It is eight o'clock here, what time is it in Paris? Hmm, eight o'clock. That was an easy conversion.
What time is it in Tunisia? Wow that was an easy one too. How about Sydney? Will you look at that, it is eight o'clock there too. Thanks for your feedback, Person.
Time zones are a funny thing and we have only scratched the surface here. If you're curious to learn more, we encourage you to do a little research. Let us know what else you find out! Hi, Courtney! It sounds like you have a certain scientist on the mind! Check out Wonders and to learn about Nikola Tesla! Hi, Allison! We do, too! We hope you use the search box to find the Wonders all about turtles! Hello, Ishaan! We hope this Wonder was helpful!
We encourage you to explore the science Wonders here at Wonderopolis! Hi, Allis! Thanks for joining the discussion! Do you like turtles, too? They are super cool animals! Use the search feature to find Wonders related to turtles! Hi, cailee! One reason some countries are 30 minutes different is because it is halfway between two different time zones 1 hour different , so it chose to be 30 minutes.
We hope this Wonder was helpful, too! The time zone names may be completely different, even though the UTC offset is the same. There are also 25 military time zones which follow the rule of 1 hour per 15 degrees longitude. J Juliet Time Zone is occasionally used to refer to the observer's local time. Another point that can cause confusion is that some time zone's names in totally different places have exactly the same abbreviation.
In many parts of the world, especially in countries with only one time zone, time zone names are not commonly used at all. Mobile Newsletter chat close.
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