The working and function of the international date line

The International Date Line, widely known as the Prime Meridian or the dateline, is a fictitious line that runs in between the two poles namely the north and the south which divides every day of the calendar of every country and helps in the decision of the time zone of the country.

It runs parallel with the 180-degree degree longitude line commonly known as the prime meridian for most of its course, but departs east over the Bering Strait to not to split Siberia in its course in two days’ time difference, and afterwards in the western direction in Alaska to encompass the Aleutian Islands.

Similarly in New Zealand, again it goes to the east side to avoid splitting some island groups and to maintain the same day in New Zealand. This happens on the southern side of the equator.

The working of the International Date Line

 For a small imagination let us understand the working with an example. Let’s pretend you’re flying from the U. S. to Tokyo, and you’re leaving on Wednesday morning. Since you’re flying west, the passage of time is delayed considering the time zones as well as the velocity upon which the airplane is flying. When you cross the international timeline, though, it’s suddenly Thursday. However, in going back from Tokyo to the U.S., the complete opposite of the phenomenon. you’ll see that the day is changing to later very quickly crossing time zones. Whereas, as soon as you fly through the international dateline/timeline, it suddenly changes to Tuesday (a day earlier).

In simple words, if we travel eastward of the international timeline the day gets changed to an earlier day. However, if we travel in the west direction, the day changes to a later day like we have moved forward by 24 hours. Or we can say travelling east one can decrease a day and travelling west one can increase a day in his/her watch.

The function of the International Date Line

 The International date Line is the result of the global usage of time tracking programs set up such that regional noon roughly coincides with the time when the sun passes the relevant longitude line. It gives us a standard protocol to change our time as per travelling such as said earlier where People heading eastward throughout the Date Line move their clocks backwards by one day, while those travelling westbound change theirs forward one day. Which is the main function of the International timeLine.

 Another function of it is the decision of the time zone of every country. As you can see in the case of India, the time zone of India is IST (Indian Standard Time) which is +5:30 hours of GMT (Global Meridian Time) at which the time is considered to be 00:00. Similarly, every country has its time zone about the GMT, such as New York has a time zone of -4:00 GMT. For example, if it is 00:00 at GMT it will be 5:30 AM the next day in India and it will be 8:00 PM a day earlier in New York.

Nautical Date Line and the International Date Line

Unlike the International Date Line, the Nautical date line is a quite similar concept with a slight difference having been the international date line is not governed by or does not come under the governance of any country’s law. However, the Nautical dateline is another dateline that runs from the north pole to the south pole in the 180-degree prime meridian and is governed by the agreements set by various countries.

Conclusion

To sum up, the IDL or the International Date Line is the standard date line about which every day changes. It works by deciding the day by travelling eastward or westward. For example, if we travel east through an International Date Line, we have to change our time by a few hours or a day earlier, similarly, if we travel in the west direction, we have to change our time by a few forward hours or days. By deciding these rules, it acts as a standard in the decision of time of various countries. Such as the time zone of India and New York and others.