Railway Exam » Railway Exam Study Materials » Geography » Learn more about the popular Prime Meridian

Learn more about the popular Prime Meridian

Prime Meridian is an imaginary longitude at which the value of the prime meridian is presumed to be zero. Learn more about the popular Prime Meridian.

The prime meridian is an imaginary longitude line on the surface of land geography where the longitude is assumed to be zero. At this point, the value of the prime meridian is assumed to be zero. Furthermore, the prime meridian and the anti-meridian together comprise a circle. Moreover, these two meridians divide the whole sphere into two prominent hemispheres. For naming the two hemispheres, the prime meridian is the basis for categorization. The hemisphere lying towards the east of the prime meridian is known as the Eastern hemisphere. On the other hand, the hemisphere lying on the western side of the prime meridian is termed the Western hemisphere.

What is Greenwich Meridian?

For defining a single prime Meridian for Earth, many scientists made conventions to find a Prime meridian for different regions. However, Greenwich Meridian was adopted as the international meridian for the conventional time distribution of Earth. The newly adopted IERS Reference Meridian is extensively used today to define the conventional time which shows a slide deviation from the Greenwich meridian.

History

The need for a prime meridian was firstly generated in the year 1851 by Sir George Airy. Earlier for reference purposes, they used to mark their tonnage and ships as meridian on the maps. Later on, in October, a conference was held under the leadership of Chester A. Arthur, former US President. At this conference, 41 prominent delegates were invited from 25 leading nations. The conference was named the International Meridian Conference and was organized in Washington, D.C., United States. With the support of the members, the conference approved the meridian passing through Greenwich as the official prime meridian. This happened because the Greenwich meridian was quite popular among the common people. However, the only country that refused to accept this decision was France and for several decades they used the Paris meridian for mapping purposes.

Difference Between Eastern and Western Hemisphere

Parameters of Comparison

Western Hemisphere

Eastern Hemisphere

Location-based on Prime Meridian

The Western Hemisphere is situated on the western side of the prime meridian.

The Eastern Hemisphere is situated on the eastern side of the prime meridian

Location-based on International Date Line

Ironically, the Western Hemisphere is situated on the eastern side of the International Date Line.

The Eastern Hemisphere is situated on the western side of the International Date Line.

Earth areas

The areas of the Western Hemisphere include the land of America, the western land of the British subcontinent, and northwestern regions of Africa.

The areas of the Eastern Hemisphere include the land of Australia, Asia, and some parts of Africa.

Countries having Prime Meridian

The prime meridian passes through many countries across the globe. While there is a conflict in Antarctica, whether it is approved as a country or not, we still have included it under the list. The prime meridian passes through mainly eight countries and the list of countries is as below:

  • France
  • United Kingdom
  • Spain
  • Mali
  • Burkina Faso
  • Algeria
  • Ghana
  • Antarctica
  • Togo

UTC

Let us learn more about the popular Prime Meridian uses and standardizing. UTC is an acronym extensively used in defining the time of a particular country. UTC refers to the Coordinated Universal Time in which a standard time is given for the whole country according to the prime meridian. As the Equator is the basis for defining the latitude and longitude positioning in the same way, UTC defines the standardization of time. According to this, the time zones are divided into 24 zones throughout the world.

While talking about India, the standard time across India is UTC + 5:30 and is named as Kolkata time zone. Similarly, the time zone of Russia is UTC + 3.

International Date Line

The International Date Line is marked at 180 degrees longitude towards the prime meridian. This line divides the whole sphere into two date sections. As we cross the International Date Line and move towards the west, one day will be added. Also, as we cross the International Date Line and move towards the east, one day will be subtracted.

IERS Reference Meridian

The 0-degree prime meridian is known as the IERS Reference Meridian (IRM). Since to rectify the deviation of the Greenwich Meridian, IERS Reference Meridian is placed at 335 feet (approx 102 meters) below the Royal Observatory’s latitude which is located at Greenwich. Also, IRM is located at 5.3 seconds to the George Biddell Airy’s 1851 transit circle’s eastern side. IRM is the basis of the Global Positioning System (GPS) and has mainly two key versions. The former is known as the International Terrestrial Reference System (ITRS) and the latter is known as the International Terrestrial Reference Frame (ITRF).

Conclusion

The article is about the popular Prime Meridian, its uses, and reference which led to the standardization of many issues. The prime meridian has introduced a single time frame throughout the world. This time frame differs from latitude to latitude and is termed a time zone. The whole globe is divided into 24 time zones which are followed by the countries. Also, the prime meridian passes through 9 countries. Also, prime meridian is used to authenticate the measurement of date which is termed standard. While going to the West increases a day, going to the East decreases a day.

faq

Frequently Asked Questions

Get answers to the most common queries related to the Railway Examination Preparation.

While talking from the point of view of GPS, is the Greenwich meridian located at zero degrees?

 No, according to GPS, the Greenwich meridian has a slight deviation of 5.3 seconds to the east.

What makes Greenwich famous, to get selected for prime meridian?

The famous Royal observatory is situated in Greenwich and makes it popular for selecting as a meridian.

Can we calculate the approximate deviation of the prime meridian from the GPS?

Yes, the prime meridian shows about 102.478 meters deviation towards the east.

Who has been given the charges for the maintenance of the IERS Reference Meridian?

International Earth Rotation and Reference Systems Service (IERS) is the governing body that is responsible for reta...Read full

Crack Railway Exam with Unacademy

Get subscription and access unlimited live and recorded courses from India’s best educators

Notifications

Get all the important information related to the Railway Exam including the process of application, important calendar dates, eligibility criteria, exam centers etc.

Access more than

6,505+ courses for Railway Exams 

Get the learning app

Download lessons and learn anytime, anywhere with the Unacademy app