why do we have different time zones in the world
As the rotates on its axis, the
shines on only one part of the Earth at a time. While the sun shines where you live, itвs nighttime somewhere else. When youвre eating your breakfast cereal, children in Paris are finishing the school day and children in Moscow are eating dinner. Children in Bangkok are going to bed and children in Sydney, are getting up for the next day of school. It wouldnвt make sense for us to be on the same time. Instead, countries all over the world are divided into time zones, based loosely on longitudinal bands. Large countries, such as the and, may be divided into three or more time zones, but most countries fall in one zone. Fun Facts about Time Zone for Kids Many countries follow daylight saving time, which is designed to allow people to enjoy more waking hours during daylight. In most of the U. S. , our clocks spring forward one hour in the spring. They fall back one hour in the fall. As you move around the globe, youвll eventually reach a place where the time is either one day ahead or behind. This place is known as the International Dateline. Australia and a few other places are a day ahead of you. When itвs Monday where you live, itвs Tuesday there. Before you call a friend overseas, make sure you know what time it is there. Otherwise, you might call your friend at 3:00 in the morning. Who wants to talk then? Time Zone Vocabulary Rotate Axis Time zone : division of time, based on the Earthвs rotation and the Sunвs path All about the Time Zone Video for Kids A video explaining why time zones were established and how it came to be. Time Zone Q A Question : How do you adjust the time when you cross into a different time zone?
Answer : Cell phones and automatically adjust to a new time zone. You can move a watch forward or backward. Enjoyed the info? and. For lengthy info click. Last Sunday (October 26), British clocks went back from British Summer Time to Greenwich Mean Time, restoring the whole country to the internationally unified line from which all time (and distance) is measured: Greenwich Mean Time, which is derived from the Greenwich Prime Meridian, running through London. But why London? Why not Istanbul or Indianapolis? Well, let s see, shall we? When you re dividing up a globe into sections so that time works in the same way wherever you are, it s important to start somewhere. So just as the Equator splits the planet in half widthwise, the Greenwich Prime Meridian does likewise with length, sitting at longitude 0В 0 00 and passing through the right hand side of Great Britain. It passes through Cleethorpes in the North and ends at Lewes in the south. It then slices on down through France, Spain, Algeria, Mali, Burkina Faso and Ghana. Due to the direction that the planet is spinning in, everything to the east is officially in the future, everything to the west is in the past. Unlike the Equator, which is drawn on the furthest point from the rotational axes of the planet, the prime meridian for international time could have been drawn anywhereвan hour to the east, for example, or five hours to the westвin scientific terms it doesn t matter at all so long as everyone s 8 am is near sunrise and everyone s 8 pm is getting on for sunset, and the gridlines that show location across the planet are the same for everyone.
But this hasn t always been the case. In the 19th century, time was not uniform. Communitiesвwhether cities or countriesвkept their own local time, which meant they created their own prime meridians, starting whenever it seemed right. With the advent of railways (and their timetables) and the telegraph, it became clear that some kind of international accord would need to be reached, time would need to be divided into 24 hour-long segments across the planet so that 6:15 would not suddenly become 6:30 whenever a train arrived at a new station. In 1884, the International Meridian Conference met in Washington to decide which line would be THE prime meridian for the entire world. It would not be an easy discussion. Delegates from 25 nations had to agree something that would lend one country a certain prestige and status. Washington, London, Berlin and Paris were all hoping to secure the honor, and with no second prize on offer, the conversations got fairly heated. Britain was in a strong position from the start, nearly three-quarters of the ships on the sea were already navigating with charts that used the Greenwich Prime Meridian, and the U. S. railways were also using a timetable based on Greenwich Mean Time as the standard to ensure the trains ran on time. But that s precisely half of the problem; the Greenwich Prime Meridian represents an eternal NOW, travel in one direction and you re going back in time, the other way takes you forward. But what happens when two people set off in opposite directions from Greenwich and meet on the other side of the world, one adding hours, one taking them away?
What time is it then? That line on which they meet is the International Date Line. One side is half a day ahead of G. M. T. and the other is half a day behind. Therefore it s important that this does not run through densely populated areas, or you d be getting your post before it was sent. With the Prime Meridian based in London, the International Date Line can skirt around Alaska and run down the Pacific Ocean without too many problems, apart from the islands it encounters along the way, who have had to decide which side of the dateline they are on. Put the Prime Meridian anywhere else, and you re splitting whole countries down the middle, using a calendar. With all these factors at play, the decision was put to a vote and Greenwich won by 22 to one. France and Brazil abstained, and San Domingo was the sole vote against. Not that everyone was happy, as the British Empire was in full blossom at the time and many countries would have preferred a more neutral choice, and even now, 130 years later, some countries shift time to suit their needs on a local level. French time is an hour ahead of British time, for example, because it makes more sense to share a timezone with your landlocked neighbors than the island over the sea. Having said that, modern technology has also had an effect. It seems GPS maps show that the true Prime Meridian actually lies 100m to the east of the Greenwich Observatory, which plays host to a ceremonial brass strip supposedly running along the line (see image above). A small crumb of comfort for San Domingo, there. See more:
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