The term "in mundo", translated from the Latin, literally means "in or on the world". What we are saying here is that "in mundo" techniques make use of calculations of a body's true or actual position in the celestial sphere with respect to the observer's Great Circles (the Horizon, Meridian and so forth). In astrology the term "in mundo" refers to a type of chart, listing or speculum of planets and points calculated with reference to planes other than the Ecliptic. Some of these planes include the Prime Vertical, Horizon, Meridian and Celestial Equator.
Distances along the above planes are measured in what are called longitude, azimuth and right ascension respectively. Distances north and south of planes are called orthogonal referents – latitude, altitude and declination respectively in these cases.
Ecliptic based astrology projects a body's location two-dimensionally in longitude along the Ecliptic and combines it with the intersection or nodal points of the Midheaven (where the Meridian intersects the Ecliptic) and the Ascendant (where the Horizon intersects the Ecliptic) and other nodal points such as the EP (East Point is where the Horizon intersects the Ecliptic point that is rising on the Celestial Equator) and VX (Vertex where the Ecliptic intersects the Prime Vertical in the West) among others. Very few astrologers are aware of the fact that the orthogonal referent with respect to the plane of the ecliptic is called latitude. This latitude component bears watching and investigation.
