RAS question
The Prime Meridian (0° longitude) passes through:
Correct answer: (C) Greenwich, London.
The Prime Meridian, or 0 degrees longitude, passes through the Royal Observatory at Greenwich, London.
Explanation
The Prime Meridian is the reference meridian from which longitude is measured east or west. Its route passes through the Royal Observatory, Greenwich, London, and it was adopted internationally in 1884. NOAA's National Ocean Service notes that the International Meridian Conference in Washington, D.C., chose a line running through the telescope at the Royal Observatory in Greenwich, England, as the meridian representing 0 degrees longitude. This made Greenwich the standard starting point for longitude. Because longitude is measured east or west from this line, the Prime Meridian also marks the division between the Eastern and Western Hemispheres.
Why the other options are wrong
- (A) New Delhi is not on the 0 degrees longitude reference line; that line is at Greenwich, London.
- (B) Washington, D.C. hosted the 1884 conference mentioned by NOAA, but the conference selected Greenwich, not Washington, as the 0 degrees longitude meridian.
- (D) Paris is not the adopted international Prime Meridian; Greenwich was adopted as the standard in 1884.
Concept
This tests the basic World Geography concept of latitude-longitude reference lines, especially the Prime Meridian as the zero-longitude baseline. RAS often asks it because map reading, time zones and hemispheric location all depend on this reference.