The latitude and longitude references are lines, not points. The reference for latitude is the line that forms a circle and consists of all points with zero latitude. That line is called the "equator". The reference for longitude is the line that forms a semi-circle and consists of all points with zero longitude. That line is called the "Prime Meridian".
The Prime Meridian is the reference line. That's the meridian of longitude that joins the north and south poles and passes through a mark on the floor of the transit room of the Royal Observatory at Greenwich, a suburb of London. By international agreement, that line is zero longitude. All others are measured east or west from it, from zero to 180°.
The "Prime Meridian" ... the one that passes through the Royal Observatory in Greenwich UK ... is the zero reference for longitude.
The longitude of a point on earth is the angle, east or west, between that point and a certain reference line on the earth. If you take a globe or a map and draw a line through all the points that have exactly the same longitude, the line you get is the meridian of that longitude. The reference line is the meridian of zero longitude, called the "Prime Meridian". On that line are all the points on earth that have zero longitude. The line joins the north and south Poles, and passes through the Royal Observatory at Greenwich, a suburb of London.
A meridian is a line of constant longitude.
The Prime Meridian is defined as the zero reference of longitude.
By international agreement about 200 years ago, the zero-reference line of longitude is the Prime Meridian.
The latitude and longitude references are lines, not points. The reference for latitude is the line that forms a circle and consists of all points with zero latitude. That line is called the "equator". The reference for longitude is the line that forms a semi-circle and consists of all points with zero longitude. That line is called the "Prime Meridian".
The equator is defined as the zero reference line of latitude.
The reference for longitude ... the definition of 'zero' longitude ... is the Prime Meridian. That imaginary line joins the north and south poles, and runs through Greenwich, a suburb of London, UK.
The Prime Meridian is the reference line. That's the meridian of longitude that joins the north and south poles and passes through a mark on the floor of the transit room of the Royal Observatory at Greenwich, a suburb of London. By international agreement, that line is zero longitude. All others are measured east or west from it, from zero to 180°.
The "Prime Meridian" ... the one that passes through the Royal Observatory in Greenwich UK ... is the zero reference for longitude.
The longitude of a point on earth is the angle, east or west, between that point and a certain reference line on the earth. If you take a globe or a map and draw a line through all the points that have exactly the same longitude, the line you get is the meridian of that longitude. The reference line is the meridian of zero longitude, called the "Prime Meridian". On that line are all the points on earth that have zero longitude. The line joins the north and south Poles, and passes through the Royal Observatory at Greenwich, a suburb of London.
A meridian is a line of constant longitude.
The center line of longitude is the line that runs from the North Pole to the South Pole and divides the Earth into eastern and western hemispheres. It is also known as the Prime Meridian, which passes through Greenwich, England, and is used as the reference point for measuring longitude.
The equator is the zero reference line for latitude, and the Prime Meridian is the one for longitude.
By international agreement, the line that defines the origin of longitude is the Prime Meridian. It joins the north and south poles and passes through the Royal Observatory at Greenwich, England.