to split the earth in half
Earth can be divided into an infinite number of meridians, but only one of them is prime, which means most important or number one. The Prime Meridian is 0° longitude. The complete set of meridians covers a total of 360°, which is evenly divisible by 30.
Antarctica
Meridians east of the prime meridian are labeled with the letter E, which stands for east. The prime meridian itself is labeled as 0° longitude, and meridians to the east are assigned increasing positive longitude values.
The Prime Meridian is numbered zero degrees. Meridians, or lines of longitude, are numbered with increasing numbers of degrees both east and west of the Prime Meridian. On the opposite side of the world from the Prime Meridian is 90 degrees, which is also the International Date Line.
No, the Prime Meridian is not shorter than other meridians; all meridians are of equal length. Each meridian, including the Prime Meridian, runs from the North Pole to the South Pole, making them all approximately 20,000 kilometers long. The Prime Meridian is simply the reference line for 0 degrees longitude, while other meridians are measured in degrees east or west of it.
The Prime Meridian The International Date Line
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The longitude of every point on the Prime Meridian is zero.
Meridians of Longitude All of the other meridians; the lines of longitude.
Prime Meridians.
The Prime Meridian and the International Date Line
The Prime or Greenwich meridian. 0 degrees longitude