Culmination Point

babylonian: ziqpu · latin: culmen / Medium Coeli · greek: μεσουράνημα — mesouranema

Definition

The highest point a star or planet reaches in its daily arc across the sky — the moment of crossing the local meridian above the horizon. In Babylonian astronomy the culmination point is named by the Akkadian term ziqpu, which Reiner and Pingree gloss as the upper terminus of a body's progressive ascent. In the later Western tradition the same point coincides with the upper meridian or Medium Coeli (MC), the rotational axis around which the diurnal motion of the heavens is observed.

In Tradition

Across the Babylonian stellar-observational tradition the culmination point is treated as the terminus of progressive vertical motion: Reiner and Pingree document the Group F Venus omens of BPO 3 in which the protasis 'Venus goes progressively higher to the ziqpu' marks the upper limit of a body's ascent. In the Hellenistic-and-later Western tradition the same point is read as the angle of public expression, the chart's vertical axis, and the high point of a fixed star's diurnal arc relative to the observer.

In Practice

Practitioners use the culmination point in three distinct lineages. In Babylonian-derived observational astronomy the ziqpu apparatus tabulates which star is on the meridian at a given moment as a pre-clock time-keeping reference; the interval between two events is read off the ziqpu sequence in time-degrees (UŠ; 1 UŠ = 4 minutes of celestial rotation). In Hellenistic and later Western horoscopic practice the culminating planet — the planet nearest the upper meridian — is read as the planet most prominent in public-facing significations, with the MC carrying the same valence. In fixed-star work a planet conjoining a fixed star by paranatellonta culmination — the planet on the meridian when the star also culminates — is read as activating the star's combined symbolism at the peak of its diurnal expression. The technique is latitude-dependent, since the altitude of the culmination varies with the observer's geographic latitude.

Historical Origin

The culmination point is documented as the Akkadian ziqpu in MUL.APIN Tablet I iv 1-30 (Neo-Assyrian canonical edition, c. 1000-700 BCE) and in the Babylonian Venus omens BPO 3 Group F edited by Reiner and Pingree (K.3601, ND 4362, K.2346). The Hellenistic-tradition equivalent — the upper-meridian / Medium Coeli — appears across Ptolemy, Valens, and Paulus Alexandrinus, and is carried unchanged through the Arabic, medieval Latin, and Renaissance English literatures into modern Western practice.

Etymology

Origin: Latin / Akkadian. Meaning: Culmination renders the Latin culmen, the summit or topmost point; the Babylonian-tradition equivalent ziqpu in Akkadian carries the sense of peak or tip..

Definition

In Tradition

In Practice

Historical Origin

Etymology

Further Reading