Longitude
Longitude, or meridians, are lines that run from north to south across the globe. The starting point for this system (0°) is the British Royal Observatory at Greenwich, England. This prime meridian was chosen at a time when England was dominant in making maps and navigating.
Locations west of this line have a longitude of up to 179° west; those to the east have a longitude of up to 179° east. The 180th meridian is exactly on the opposite side of the globe, in the middle of the Pacific Ocean. It is also called the International Date Line. Travelers who travel westwards across the dateline change to the following day .
The distance between each degree of longitude varies. It is largest at the equator (69 miles) and shortest at the poles (0 miles), where the lines come together .
The Prime Meridian at Greenwich, London
Image: PJsg1011, CC BY-SA 4.0, via Wikimedia Commons
Words
- degree = unit by which the lines around the Earth are measured
- distance = space between two places
- dominant = leading, number one
- equator = line around the middle of the Earth
- exactly = correctly , in detail
- globe = Earth
- International Date Line = imaginary line that goes through the middle of the Pacific Ocean from the North to the South Pole. The date on the west side is one day earlier than the date on the east side
- navigate = to guide a ship in a certain direction
- observatory = round building where you can use a telescope to study the stars and planets
- opposite = other side
- prime meridian = the imaginary line from the North to the South Pole that passes through Greenwich , England and marks 0° longitude, from which all other longitudes are measured
- vary = different