7 little facts about time zones

You wonder about time? Why are there so many different time zones in the world? Let's find out!

1. GMT and UTC

GMT stands for Greenwich Mean Time, meaning average hours at Greenwich. This is the first international standard time calculation method used. It was measured at the Royal Greenwich observatory in Greenwich, England. This place is conventionally located on the meridian 0, latitude 51,28,38N (North equator).

GMT time is the first international standard time method used.

GMT is calculated from noon one day to noon the next day. Since 1925, this unit has been replaced by UTC (short for Coordinated Universal Time, meaning coordinated universal time). A day is now counted from midnight the previous day to midnight the next day. UTC is calculated based on the atomic frequency standard and is more accurate when calculating solar time from a point on the surface of the Earth.

Because the Earth rotates around its own axis at an unstable speed, it is necessary to add a leap to UTC, and keep it for about 0.9 seconds. So can write T23: 59: 60 (sometimes there are 60 seconds, no 59 seconds). On January 1, 1972, UTC officially became an international standard, although GMT was still in widespread use.

2. Boundaries of time zones

This difference is most evident in two large countries, China and India.

Time zone boundaries have a lot of differences. This is because the time zone boundary must be divided by the national border. This gap is most evident in two large countries, China and India, when both countries share a time zone across the territory.

3. Time zone horizontally

At a place in Australia, due to business competition reasons, it is necessary to adjust the difference by 30 minutes.

The time zone is divided by vertical and longitudinal axis, based on the movement of the Sun from East to West, but not everywhere follows this natural rule. At a commercial district in Adelaide, Australia, the time zone is normally an hour slower than Sydney but due to business competition reasons it is necessary to adjust the difference by 30 minutes.

4. World without time zone

When there are clocks, people calculate time based on sunrise and sunset.

Before the GMT standard was launched, time was calculated by observing the sky or the ground. Some of the more sophisticated time-calculating techniques are watching the Sun at its peak (in the sky) at noon or in the shadow (the shadow of the object changes with the movement of the Sun).

When there are clocks, people calculate time based on sunrise and sunset, so time has different between regions. This is not too big a problem because there are many restrictions from traveling between territories. As communications and transportation develop, the need to measure time begins to be realized.

5. The sun is at the peak position

The time of the Sun coming to heaven in most countries is mostly accurate, except China.

The time of the Sun coming to heaven in most countries is mostly accurate, except China. Because the border of this country is up to 240 km, while only using the same time zone. Therefore, the main position of the Sun in the Far West occurs at 3pm, Far East is at 11pm.

China used to have 5 time zones, including: Kunlun (in Xinjiang-Tibet province), Gansu, Sichuan, Zhongyuan and Changpai. But then, the country used a time zone to unify. This causes difficulties for people in everyday life. For example, people in Xinjiang work 4 hours later than others because the sun rises at 10am.

6. A common time zone for the world

In any country, 9am must be daytime and 10pm must be night, cannot be changed.

Is there a common currency, a common language? So will it be easier and simpler to have a time zone? And when going from one country to another, there is no need to reset the clock. But the reasons why the world needs so many time zones are: The Earth turns 15 degrees per hour, one day is 360 degrees. This area set a faster time than the area before an hour (except Japan). This shows exactly when the Sun is highest. In any country, 9am must be daytime and 10pm must be night, cannot be changed. Except in the Northern regions of Northern Europe, where there are 6 months and 6 months of nights.

7. The smallest time zone

The small island in the Baltic Sea is divided into two time zones according to the national boundary.

The small island in the Baltic Sea has a very small area, the distance between the farthest points is 80-300 meters. The island is owned by both Sweden and Finland, each side is half, so its time zone is divided into two, according to the national boundary. This is the important place that helps the two countries on their calculation, their time zone format.