Source of orientation of a monument

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 leads to determine the astronomical source of orientation of any monument. It was conceived on the basis of the most recent algorithmic developments in astrometry and photometry. 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 at the epoch considered, that is to say, a list of stars visible with the naked eye whose sighting of the appearance or transit or disappearance position in the night or twilight sky explains at best 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.

Orientation of a Monument

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This software invites you to determine the astronomical source of orientation of any monument erected between -4712 and 2017. Do do so, it uses data issued from the Hipparcos catalog (coordinates of 5043 stars visible with the naked eye), combines various astrometry (relative to the positioning of the stars in the sky) and photometry (relative to the brightness of the observed star and the conditions of local visibility) algorithms published within the scientific articles whose list appears below.
Free tests of this software are available within the Client Area. The access to the user interface of this software is made on payment : 35 euros, which can be paid via the Paypal secured paiement system (right button). This amount includes an unlimited access to the user interface and a free access to any future updates.

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