# Is the equator the longest degree of length

## The graticule of the earth

An important prerequisite for the geographical consideration of a place is its precise knowledge of the location. For example, the location of an area in relation to the equator is important for its climate. It is therefore necessary to be able to apply our knowledge of the graticule correctly.

### Latitude

In order to be able to determine a point exactly on our earth, it is necessary to orientate yourself. The word orient (lat. Orient - the East) actually means "looking for the East". We understand this to mean "indicating the location of a place". An orientation system was introduced for this purpose. When looking at a globe, we recognize it by auxiliary lines that circle the globe as circular lines in a north-south or west-east direction.

The equator divides the earth into a northern and a southern hemisphere. The equator is a circle whose center corresponds to the center of the earth. It is also the longest parallel. In the northern and southern direction, one imagines circles that become smaller and smaller in the direction of the poles.

If the earth were an "exact" sphere, a degree of latitude would be equal to 1/360 of the circumference drawn around the earth's surface. However, the earth is flattened at the poles. As could be determined astronomically, the actual latitude of a degree changes between the equator and the poles. The latitude of a degree at 45 degrees north or south, the so-called mean degree, is 111,131.9 meters or approximately 111.13 kilometers.

### Degrees of longitude

Longitudes run through the north and south poles. Their distance from one another becomes smaller and smaller in the direction of the two poles. All longitudinal circles intersect in the poles.

Half a longitude is a meridian. It runs from the north to the south pole. If you cut the globe, you get a circle. Because a circle has 360 degrees, one also counts 360 meridians. The meridian that runs through the former Greenwich Observatory is called the Prime Meridian. The definition of the equator was simply because it is the largest in circumference. It was difficult to determine a prime meridian. Before agreeing on a prime meridian, each country could define its own prime meridian. As a result, many world maps from the 19th century do not have a standardized grid. This problem was solved in 1885. Each latitude and longitude is divided into 60 minutes and each minute into 60 seconds. This is so that every point on earth can be precisely determined.

The length of a longitude moves from a maximum at the equator to longitude "zero" at the north or south pole. This is because longitude is measured as the arc of a given parallel, and these circles of latitude decrease in radius with increasing distance from the equator. At the equator the distance between longitudes is 112.09 kilometers, towards the north or south pole this distance decreases. Longitude is also measured in hours east or west of the prime meridian, where one hour corresponds to 15 degrees and one minute to 15 angular minutes. The longitude of New York City can be given as 74 degrees or as 4 hours 56 minutes west of Greenwich.

### Tropics

Tropics are called the two circles of latitude on the globe, which are at the same distance from the equator at 23.5 degrees north or south latitude. The northern tropic is called the "Tropic of Cancer", where the sun is at its zenith on June 21st (90 ° to the surface of the earth). The Tropic of Capricorn is called "Tropic of Capricorn" (December 21). At the time of the solstice, the sun reverses its apparent direction of movement from these circles back towards the equator.