Why in the world there are different schedules

Image: Slideplayer

Have you ever wondered why in the world there are different schedules between countries or even within the same country? Why, for example, within the same country such as Spain, are there time differences between peninsular time and the Canary Islands? This is why the time in each geographic region is set according to the position of the Sun on Earth. To resolve this question, we will first investigate the current calendar origin and how it has influenced the configuration of our schedule.

The first calendars created to record the division of time were based on religious beliefs and direct observation of the sun and the moon. With the progressive advances in the field of astronomy and mathematics, the calendar would adjust more and more to the one we have today.

The origin of our calendar we have to look for in the imperial era of Rome, specifically in the time of the Emperor Julius Caesar(1000 a. C - 44 a. C). This in turn comes from egyptian calendar created in 4236 BC C pointing to the Sun as a reference point. Later in 1582 Pope Gregory XIII carried out a reform giving rise to the name

Image: Slideplayer

The fact of having distributed the time in hours has a lot to do with the astronomy and other fields of human activity. As we said in the previous paragraph, for a time the task of classifying time was the work of astronomers who were based on the movements of the stars. At present, and thanks to the unstoppable advance of technology, the hours are measured by clocks with a much more exact precision than that of our astronomer ancestors.

As we said, in the world they are used different hours depending on the location of the sun with respect to the geographic location of a country. To make the allocation of hours in different geographical areas more practical, the time zones.

It was in 1870 when the engineer Sir Sandford Fleming was the first to highlight the problem of time zones. Later, in 1884 in the Meridian Conference, a meeting made up of 27 countries, the current world time system was approved.

What are time zones?

Time zones are the result of rotational motion of the earth in which the time it takes for our planet to rotate on itself is 24 hours. Taking this into account, the time zone corresponds to each of the 24 hours in which the Earth has been divided in relation to the Greenwich Meridian(0º): every 15º towards the East corresponds to one hour more while, 15º towards the West corresponds to one hour less.

All time zones are defined in relation to Coordinated Universal Time (UTC) so it is centered, as we have seen, on the Greenwich meridian. Thus, in all the terrestrial meridian the passage of the Sun takes place at noon; an hour later it passes through another meridian located 15º west of the first one and so on until midnight, where it will return to the original meridian. Therefore, all the countries that are within the same meridian must have a similar schedule, establishing the time zones from north to south in order to establish a standard time throughout the entire Earth.

The international date change line marks the change of day. This is an imaginary line located on the Pacific, coinciding with the meridian 180º. If this meridian is crossed, the date is changed.

Keep in mind that not all countries follow the UTC time zone and that they have their own pattern of hourly distribution. Within these exceptions we can find China who despite being geographically located within several time zones due to its great extension, has a common time for its entire territory.

Image: Concept.de

We cannot finish this lesson without mentioning the time changes in the world which are taken in summer.

In summer, as a general rule, the clocks are moving forward in order to gain one more hour of daylight and thus get more out of daylight. On the contrary, this use is affected at dawn. The time of the time change is usually in spring for the one hour advance and in autumn for the one hour delay.

The use of sunlight is related to the energy saving. At present, some countries have questioned this argument and a change is being studied around the increase or delay of the time according to spring or autumn.