The Prime Meridian is defined as the origin of longitude.
The longitude of every point on it is zero.
The Greenwhich meridian also Prime Meridian is 0 degrees longitude and International Date Line roughly follows the 180° longitude or antimeridian. The antimeridian is the meridian which is 180° east or west of the Prime Meridian.
!80 degrees east of Greenwich and then one crosses over to West Longitude
The Prime Meridian is located at 0 degrees longitude.
Morocco
Shanghai, China is approximately 121 degrees east of the Prime Meridian, which is the internationally recognized marker of 0 degrees longitude.
Distance East or West of the prime meridian is measured in degrees of longitude.
180 degrees
180 degrees
180°
The prime meridian (designated as zero) runs from pole to pole, passing through the Greenwich Observatory, London, England. Lines of longitude to the east of the prime meridian are so many degrees east, and to the west of the Prime Meridian are so many degrees west.
Starting from the Prime Meridian and going either east or west, you'll cover 360 degrees of longitude before you find yourself back at the Prime Meridian again. Half-way around a sphere corresponds to 180 degrees. If you and your friend both start out from the Prime Meridian, and one of you travels east around the globe and the other travels west around the globe, you'll eventually meet each other. If you both travel exactly the same distance, then you each cover 180 degrees of longitude, and you meet exactly on the other side opposite the Prime Meridian, in the middle of the Pacific Ocean, at 180 degrees longitude, both east and west.
New Zealand ranges in longitude between roughly 166.47° East to 178.55° East. Longitude is measured from the Prime Meridian, so those are the angles if you start at the Prime Meridian and travel eastward. Traveling westward from the Prime Meridian, the corresponding angles are 181.45° and 193.53° .