Introduction

From the Vth millenium before our era dates the building of the very first megalithic monuments (menhirs, dolmens, cromlechs, ...). Most of these standing stones are characterized by a specific astronomical orientation : they were often built facing the rising or setting position of a bright celestial object (Sun, Moon, star, ...), indeed. It is the same for most of the later monuments dating from the mesopotamian, the egyptian, the mayan, the inca, ... periods.

This software leading to determine the astronomical source of orientation of any monument was conceived on the basis of the most recent algorithmic developments in Celestial Mechanics, Astrophysics and Optics. Since it takes into account the geographical (latitude, longitude and altitude of the site chosen for erection) and meteorological (temperature and relative humidity of the ambient air) conditions of observation, as well as the visual acuity of the stargazer, that is to say, our ability to distinguish a bright source in the background sky, this original software will give you results in quite good accordance with what was really observed : a list of stars visible with the naked eye whose appearance or transit or disappearance position in the night or twilight sky possibly led to the alignment of the monument considered. In some cases, the heliacal rising or setting of a star effectively was prefered to its rising or setting in the dark sky - mainly for worship reasons.

Fill in the form with the date of erection of the considered monument - between 4712 BC and 2012 AD -, with its azimuth of orientation and the latitude and altitude of the place chosen for observation as well as with the visual acuity of the observer. The software will then give you a list of stars of apparent magnitude smaller than 4 whose rising or transit or setting position was possibly used to align this monument. It will then be possible for you to deepen your search by determining the rising or transit or setting azimuth of each one of these stars in the dark sky and the twilight sky. Among the candidate stars, always favour the brightest ones ! You will then know with a great probability the star used to align the considered monument.

A free test of this software is available. Use it to determine the star chosen to align the temple of Hathor at Dendara, Middle Egypt, around 50 BC.

Author

Karine Gadré, Culture Diff' company-head.
Dates of first publication and successive updates : november 2003 / september 2006
This software was conceived within the context of the doctoral dissertation I prepared at the Astrophysics Department of the Midi-Pyrenees Observatory, Toulouse, France, on the basis of the most recent developments into Celestial Mechanics and Optics. It led to determine the astronomical source of orientation of the pyramids of Egypt and of the temples of Isis and Hathor at Dendara.

Access to the user interface

The price of this original astronomy software is 35 euros. This amount includes an unlimited access to the user interface and a free access to its possible updates. To purchase this software by credit card or PayPal balance on the PayPal secure payment server, add it to your PayPal Cart. To purchase it by cheque, add it to your Culture Diff' Cart.

Exclusively at Culture Diff'

Make a free test of this sofware next discover its numerous functionalities and possible use.

Further information

(AstroEgypto) The round Dendara zodiac. The temples of Isis and Hathor.
(AstroEgypto) The astronomical orientation of the pyramids of Egypt
(HistoSciences) Astronomie antique et moderne : d'observations en modélisations toujours plus poussées

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