Planetographic Coordinates

Planetographic coordinates are coordinates used to map the surface of a planet or a satellite. The planetographic longitude of a point on the surface is the dihedral angle between the meridian of the point and a chosen origin meridian. It is counted in a direction opposite to the rotation of the body, from the origin meridian, from 0° to 360°. The planetographic latitude of a point on the surface is the angle made by the normal to the surface at that point with the equatorial plane of the body. It is counted from the equator of the body from 0° to +90° towards the north pole and from 0° to -90° towards the south pole.