Astronomical source of orientation of a monument

In brief

Since the appearance of our species on Earth, humans and stone have had a very special relationship. So that Prehistory, which began about three million years ago, is divided into periods called Paleolithic, Mesolithic and Neolithic. Both their respective names and their succession underline the evolution of our relationship with stone - from the creation of the first lithic tools to their polishing through their geometrisation and microlithisation, for essentially everyday purposes: hunting, butchering, clearing, ploughing, harvesting, construction, etc. Logically, the use of stone to record the occurrence of events that have a significant impact on our life on Earth - such as the succession of the seasons of the year - follows. Thus, most of the megalithic complexes are oriented towards the positions of sunrise or sunset at various key times of the year: winter solstice, spring and autumn equinoxes, or summer solstice. The same applies to the stone monuments erected during Antiquity... unless, for cultural or worship reasons, some particularly bright stars were sometimes preferred to the Sun?

This software designed during my PhD thesis invites you to accurately determine the astronomical source of orientation of any monument erected since the year 4713 before our era. To do so, it uses data issued from the Hipparcos catalog (coordinates of 5043 stars visible with the naked eye), combines various algorithms of astrometry (relative to the positioning of the stars on the sky) and photometry (relative to the brightness of the object sighted and the local visibility conditions) borrowed from the scientific publications mentioned below.

In detail ...

The erection of the very first stone structures (menhirs, dolmens, cromlechs, circles and alignments of standing stones, etc.) dates back to the fifth millennium before our era. Most of these megaliths or megalithic complexes present a particular astronomical orientation: solar, lunar, or even stellar. The same applies to later stone monuments - temples, tombs, pyramids, erected by the Egyptian, Mesopotamian, Mayan, Inca civilizations, as well as the various peoples who followed them.

This software leading to determine the astronomical source of any monument erected since 4713 before our era (beginning of the Julian era in astronomy) has been conceived on the basis of the most recent algorithmic developments, both in astrometry (branch of astronomy dedicated to the determination of the positions and motions of the stars) and in photometry (branch of astronomy related to the measurement of the energy carried by the light particles emitted by distant stars). Since it takes into account the local geographical (latitude, longitude and altitude of the construction site) and meteorological (temperature and humidity of the ambient air) conditions, as well as the visual acuity of the observer, i.e. our ability to distinguish a bright spot against the background of a night or twilight sky, this unique software will provide you with results that are in line with the observed reality: a list of stars visible to the naked eye whose position of appearance in the eastern sky or culmination in the local meridian or disappearance from the celestial vault, in the night or twilight sky, explains the astronomical orientation of the monument under consideration - of its main axis or of one of its faces. The heliacal rising or setting of a star was sometimes preferred to its appearance or disappearance from the night sky, in fact - mainly for worship reasons.

This software designed during my PhD thesis invites you to accurately determine the astronomical source of orientation of any monument erected since the year 4713 before our era. To do so, it uses data issued from the Hipparcos catalog (coordinates of 5043 stars visible with the naked eye), combines various algorithms of astrometry (relative to the positioning of the stars on the sky) and photometry (relative to the brightness of the object sighted and the local visibility conditions) borrowed from the scientific publications mentioned below.

Bibliography

Allen, C.W., "Astrophysical Quantities", Third Edition, Athlone, London, 1976.
Borkowski, K.M., "ELP 2000-85 and the Dynamical Time - Universal Time Relation", Astronomy and Astrophysics, 205 (1988), L8-L10.
Bower, F.A. et Ward, R.B., "Stratospheric Ozone and Man", CRC Press, Boca Raton, 1982
Bureau des Longitudes, "Introduction aux Ephémérides Astronomiques", EDP Sciences 1998.
Centre de Données Astronomiques de Strasbourg : http://cdsweb.u-strasbg.fr .
Chapront-Touzé, Michelle et Chapront, Jean, "Lunar Tables and Programs from 4000 BC to AD 8000", Willmann-Bell, Richmond, 1991, pp 6-7.
Garstang, R.H., "Night-Sky Brightness at Observatories and Sites", PASP101, 306-329, 1989.
Hayes, D.S., et Latham, D.W., "Rediscussion of the Atmospheric Extinction and the Absolute Spectral-Energy Distribution of Vega", Astrophysic Journal, 197, 593-601, 1975.
Hecht, S., "Visual thresholds of steady point sources of light in fields of brightness from dark to daylight", Journal of the Optical Society of America, 37, 59, 1947.
JPL Horizons : http://ssd.jpl.nasa.gov/horizons.html.
Koomen, M.J., Lock, C., Parker, D.M. , Scolnik, R., Tousey, R. et Hulburt, E.O., "Measurements of the Brightness of the Twilight Sky ", Journal of the Optical Society of America, 42, 353-356, 1952.
Krisciunas, K et al., "Atmospheric Extinction and Night-Sky Brightness at Maunea Kea", PASP 99, 887-894, 1987.
Krisciunas, K., "Further Measurements of Extinction and Sky Brightness on the Island of Hawaï", PASP 102, 1052-1063, 1990.
Krisciunas, K. et Schaefer, B. E., "A Model of the Brightness of Moonlight", PASP, 103, 1033-1039, 1991.
Meinel, A. et Meinel, M., "Sunsets, Twilights and Evening Skies", Cambridge University Press, Cambridge, 1983.
Pilachowski, C.A., Africano, J.L., Goodrich, B.D. et Binkert, W.S., "Sky Brightness at the Kitt Peak National Observatory", PASP 101, 707-712, 1989.
Pyaskovskaya-Fesenkova, E.V., "Investigations of the scattering of light in the earth's atmosphere", USSR Academy, Science Press, Moscow, 1957.
Rozenberg, G.V., "Twilight", Plenum, New York, 1986
Saemundson, T., "Atmospheric Refraction", Sky & Telescope, 72, 70, 1986.
Schaefer, Bradley E., "Atmospheric Extinction Effects on Stellar Alignments", Archaeoastronomy n°10 (JHA, xvii (1986)).
Schaefer, Bradley E., "Telescopic Limiting Magnitudes", PASP 102, 212-229, 1990
Schaefer, Bradley E., "Astronomy and the limits of vision", Vistas in Astronomy, Volume 36, pp 311-361, 1993.
Schaefer, Bradley E., "The latitude of the observer of the Almagest star catalogue", JHA xxxii, 2001.
Simon, J.L., Bretagnon, P., Chapront, J., Chapront-Touzé, M., Francou, G., Laskar, J., "Numerical expressions for precession formulae and mean elements for the Moon and the planets", Astronomy Astrophysics 282, 663-683 (1994).
Stephenson, F.R., "Historical Eclipses and Earth Rotation", Cambridge University Press, Cambridge, 1997.
Stephenson, F.R. et Morrison, L.V., "Long-Term Fluctuations in the Earth's Rotation : 700 BC to AD 1990", Philosophical Transactions of the Royal Society of London, Ser. A, 351 (1995), 165-202.
Stephenson, F.R. et Morrison, L.V., "Long-Term Changes in the Rotation of the Earth : 700 BC to AD 1980", Philosophical Transactions of the Royal Society of London, Ser. A, 313 (1984), 47-70.
Tousey, R. et Hulburt, E.O., "Visibility of Stars in the Daylight Sky", Journal of the Optical Society of America, 38, 886-896, 1948.
Weaver, H.F., "Visibility of Stars Without Optical Aid", PASP 59, 232-243, 1947.