Parallel circle

As parallels circles are called, which in mutually parallel lying levels.

In geography , geodesy and cartography , parallel circle is synonymous with latitude - a small circle whose plane is perpendicular to the earth's axis . It is cut perpendicularly by all longitudes ( meridians ).

Each parallel circle has a constant geographical latitude , which lies between −90 ° ( south pole ) to + 90 ° ( north pole ) and has the value zero at the earth's equator . If one looks at the earth ellipsoid instead of the approximate figure of the earth , a distinction must be made between the terms geographical and geocentric latitude .

In the coordinate systems of astronomy , the parallel circles - analogous to the earthly circles of latitude - are the circles of constant declination on the celestial sphere . When it comes to calculating planetary orbits , the term can also refer to the ecliptic system , meaning a constant ecliptical latitude .