Parapegma – Stellar, Planetary & Luminary Phases

.Portable Universal Sundial Medium: Bronze Dimensions: H. 6.4 cm; W. 6.1 cm; D. 2.5 cm 1st–4th century CE © Museum of the History of Science, University of Oxford

Some form of time-keeping has been essential to humanity from the earliest times. Most fundamental to this is the recognition of seasons and the phases of the moon. The ability to predict the occurrence associated with much larger cycles required reference to the movement of the planets and their various phases and stations. The conjunction of the superior planets. Jupiter and Saturn took on special meaning for periods of time beyond the seasons

The awareness of stellar cycles from a geocentric view provided knowledge of, say, the apparent rising of Sirius and the inundation of the Nile, bringing with it fertile plains for a multitude of crops. Canopus later took on a special signification in Islam.

The discovery and articulation of Saros cycles meant the ability to predict lunar and solar eclipses. It was understood that these cycles were like families or clans that revealed a cycle with both a beginning and an end.

The ability to put all of these elements together meant that a skilled astronomer or astrologer could read a system of time of extraordinary complexity and detail. It isn’t likely that anyone would need to consider all celestial events at a given time. That would rather miss the point. Parapegma is useful when there is a particular focus on a pattern of events, of interest for a particular reason. Some cultures around 3,000 years ago used the Parapegma extensively and the phases of the stars were often considered more important than other considerations, except for the seasons themselves.

This page will show Stellar, Lunar and Planetary Phases for three months periods. To view in the correct resolution, click on the image and then click again. Updated for 01 June 2018 – Greenwich Mean Time



Uranographiahis Celestial Catalogue by Johannes Hevelius1690. Detail showing  Navis Argo (The Celestial Navigator) The view is mirrored following the tradition of celestial globes, showing the celestial sphere in a view from “ouside”

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