Different times in different parts of the world. It is not a new fact that the world has different time zones. However, one of the time zone facts you may not know is how big it is or how long it stretches from one place to another. It can be a little intimidating because you are dealing with a whole world that is relatively big. But you will be surprised at how simple the explanations will be.

Time zones were unified in the late 1800s. It divided the earth into 24 parts which correspond to the 24 hours that comprise a whole day. Before that, the world was following different time zones and brought a lot of confusion. There was a time when a country had 75 different time zones. Then, scientists took over and created the present system of time zones.

How Big is A Time Zone?

In most cases, miles and kilometers are used to measure large dimensions. Yet, time zones are determined by degrees. One time zone is 15 degrees wide, but how did it become 15 degrees? It is the answer to a simple math equation: 360 divided by 24 is 15.

360 refers to the full rotation of the world in its axis. Meanwhile, 24 corresponds to the number of hours in a day. Once the earth completes its rotation, it means that 24 hours have already passed. They used the longitude to divide the 24 regions of the world.

Where Does The Time Zone Start?

Regardless of knowing that a time zone is 15 degrees wide, you must know where it starts. This will help you calculate the correct time for each zone, and the starting point for this is the 0 degrees longitude or the prime meridian. The prime meridian is an imaginary line that passes through England, where the Greenwich Observatory is located. This is why it is also known as Greenwich meridian. 

From here, every 15 degrees going to the east, you need to add one hour, and if you are going to the west, you need to subtract one hour. Here is another thing you might want to add to your time zone facts. Have you ever wondered what GMT means? GMT stands for Greenwich Meridian Time. If a time zone says that it is GMT -6, you need to subtract 6 hours. If the current time in Greenwich is 9 am, then GMT -6 is 3 am.

Are There Multiple Time Zones in A Country?

A 15-degree comprehensive time zone is not enough for a country to fit in. Countries have different sizes, ranging from less than one square kilometer to 17 million square kilometers. A small country like Monaco can fall under a single time zone. At the same time, large countries like Russia and the US can have multiple time zones. Russia, which is the largest country in the world, has 11 time zones. On the other hand, the USA and Canada have six different time zones. 

However, large countries use a single time zone even though they stretch across multiple time zones. For example, China only uses the Beijing time, which is GMT +8. Still, when you look at the map, the country is situated in 5 different time zones. The same thing goes with India. They only have the Indian Standard Time (GMT +5:30) in two geographical time zones. They are said to have a one-time zone as a form of unity in their respective country.

While half of the world is sleeping, the other half is wide awake. You don't just need time to tell when to sleep and wake up. Keeping these time zone facts in your mind will be helpful, especially if you love to travel. You can tell the time based on your location. Also, it will be thoughtful if you know these things when you have a loved one living abroad, so both of you know when is the best time to call each other.