The Medium Coeli, or the Midheaven (MC) is a point of definition in the ecliptic coordinate system. It aims to find the part of the ecliptic that corresponds to the highest point in a celestial object’s apparent daily traverse of the visible sky, midway between its ascension on the eastern horizon and descension on the western horizon. The Midheaven does not represent the point immediately overhead, (our local zenith), or even the point of the ecliptic closest to it, but the point at which the local meridian intersects with the ecliptic.

In the northern hemisphere, the more northerly the latitude of the observer, the lower down on the horizon the Midheaven point is likely to be, but it will always be the part of the zodiac that is due south at any time, indicating the point where the planets reach their highest declination in their arc between the Ascendant and Descendant. The reverse is true in the southern hemisphere where the planets culminate on the Midheaven in alignment with due north.