The longitude, λ, international with long.. «longitudo = lat., longitude = engl., frz. etc. abbreviated ´length´» describes one of the two coordinates of a place on the earth´s surface, namely its position east or west of a defined «artificially defined» north-south line , the zero meridian.. It used to be called longitude.. For the formation of the geographic length, the shape of the earth - despite its ´flattening´ at the poles - is simplified into a sphere.. The longitude is an angle that is measured from the zero meridian «0 °» to 180 ° in the east and 180 ° in the west.. The apex of this angle is the center of the imaginary globe, the thighs going from the center through the zero meridian or the meridian, on which lies the place whose geographical length is to be given..

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+ Places of the same length lie on a meridian.. A meridian runs from pole to pole and is half of a circle of longitude.. On the globe is a circle of longitude «consisting of two opposite meridians» a great circle..
+ In order to determine a point on the surface of the earth - to indicate its geographical position - an additional specification of its latitude «formerly: its ´latitude´» is required as the second coordinate ...
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§Nullmeridian

Since there is no natural zero mark for the meridians «or longitude circles», as the equator does for the latitude measurement, a zero meridian must be defined.. It was only in 1884 that the same meridian was defined globally as the central axis of a specific telescope at the Observatory of Greenwich «London» «see Historical»..

The longitude is given as the angular distance in degrees, «arc» minutes, and seconds from the zero meridian to the east «E» or west «W»..

Notes The abbreviation E for east «from ´east´ or ´est´ for east» is recommended, for example, by DIN, which governs nautical and aeronautical navigation, in order to rule out mistakes by confusing O with 0 from the outset..

The largest possible numerical value is therefore 180 degrees, where 180 ° E = 180 ° W.. Approximately along this longitude, but with significant deviations, is in the Pacific, set by the affected countries date line..

§Distance of meridians

The distance between two longitudinal circles is greatest at the equator.. There the extension is about 111 km «40 000 km / 360 ° corresponds to 60 nautical miles, the nautical mile was originally defined with a minute of arc on the Equator».. At the poles, however, all longitudes coincide in one point.. In Germany, the average value is 71.46 km «calculation basis: longitude distance a = cos «50 °» × 2 × Ï€ × r / 360 ° = 71.46 km at r = 6. 370 km»..

§HREF {https://de.wikipedia.org/wiki/Geographische_L%C3%A4nge:Auszug aus Wikipedia, der freien Enzyklopädie}


~meinwomo~womo66~fritz14~adier~wr~, 2013-01-07