Archaeoastronomy (also spelled Archeoastronomy) is, as the name implies, the combination of astronomical and archaeological studies. Specifically, it covers the intersection between the two. One aspect of this is the use of the historical record prior to the genesis of the modern astronomical discipline in order to study past astronomical events. It also may involve the use of astronomical knowledge and extrapolation to further our understanding of the historical record. The two disciplines interact constructively. Cultural anthropologists have contributed to the field of archaeoastronomy by studying the astronomy of more modern, historical cultures; this study is termed, ethnoastronomy. Astronomy is one of the few sciences where amateurs can still play an active role, especially in the discovery and monitoring of transient phenomena. ... Importance and applicability Most of human history is not described by any written records. ... Cultural anthropology, also called social anthropology or socio-cultural anthropology, is one of four commonly recognized fields of anthropology, the holistic study of humanity. ...

An example of the first sort of archaeoastronomy is the study of the extensive records of ancient China for references to "guest stars". "Guest stars," or star-like objects which appeared in the night sky, were of great interest to the observers of ancient China and were often dutifully recorded. These events have been associated with many transitory phenomena, such as comets and, particularly, supernovae. Amateur astronomy, often called back yard astronomy, is a hobby whose participants enjoy observing celestial objects. ... Comet Hale-Bopp, showing a white dust tail and blue gas tail (February 1997) A comet is a small astronomical object similar to an asteroid but composed largely of ice. ... Remnant of Keplers Supernova, SN 1604. ...

An example of the second sort of archeoastronomy is the study of solar, lunar, and stellar alignments of historical monuments. Many claims have been made that the megalithic monument, Stonehenge, represents an "ancient observatory," although the extent of its use in that regard is in dispute. Certainly Stonehenge - and many other ancient monuments - is aligned with particular significance to the solstice and equinox points. Similar claims have been made that the Great Pyramids of Egypt are aligned with the stars in the belt of Orion, in reflection of the significance invested in that constellation by the ancient Egyptians. Megalithic tomb, Mane Braz, Brittany A megalith is a large stone which has been used to construct a structure or monument either alone or with other stones. ... Stonehenge Stonehenge is a Neolithic and Bronze Age monument located near Amesbury in the English county of Wiltshire, about 8 miles (13 km) northwest of Salisbury. ... The Great Pyramid of Giza (29° 97′ 60″ N 31° 13′ 22″ E), (sometimes spelled Gizeh) is the oldest, and last remaining of the Seven Wonders of the World and the most widely recognized pyramid in the world. ... Orion, a constellation often referred to as The Hunter, is a prominent constellation, perhaps the best-known in the sky. ... Orion is a remarkable constellation, visible from most places on the globe (but not always the whole year long). ...

During the 1960s, Alexander Thom did a thorough research on megalithic monuments in Britain, and published the results is Megalithic sites in Britain (Oxford, 1967). Apart from arguing for his theory of the megalithic yard, he also argues with statistical methods that a large part of the monuments in Britain are oriented in a way so they can be used as calendars. His theory proposes that the monuments mark points on the horizon where the sun, moon and principal stars rises at seasonal extremes like midsummer, midwinter and the equinoxes. Professor Alexander Thom (1894 - 1985) was a Scottish engineer most famous for his theory of the Megalithic yard. ... The megalithic yard (sometimes abbreviated to MY) is a theoretical unit of prehistoric measurement first suggested by the Scottish engineer, Alexander Thom in 1955. ...

Some Old World sites where archaeoastronomy is being explored

• Stonehenge and other structures apparently aligned to astronomical bodies and/or events
• Newgrange
• Ballochroy
• Kintraw
• Minard, Brainport Bay, raising methodological issues
• Carnac, the Grand Menhir Brisé
• Sarmizegetusa Regia, Romania

Stonehenge Stonehenge is a Neolithic and Bronze Age monument located near Amesbury in the English county of Wiltshire, about 8 miles (13 km) northwest of Salisbury. ... Newgrange, Ireland Larger Version Newgrange (Irish Brú na Bóinne - translated as Mansion of the Boyne), located in County Meath is the most famous of all Irish prehistoric sites. ... Ballochroy is a megalithic site on the Kintyre peninsula in Scotland. ... Carnac is a village and commune in the Gulf of Morbihan, on the south coast of Brittany. ...

Some New World sites where archaeoastronomy is being explored

• Chichen Itza, the caracol
• Monte Alban, zenith tube
• Xochicalco, zenith tube
• Uxmal, Venus allignment of the "Governor's Palace"
• Teotihuacan, the pecked-cross circles as survey-markers
• Cahokia, Mirror of the cosmos

Temple of the Warriors Chichen Itza is the largest of the Pre-Columbian archaeological sites in Yucat n, Mexico. ... Monte Albán is a large archeological site in the state of Oaxaca, Mexico. ... Xochicalco is a Pre-Columbian archeological site in the western part of the Morelos, Mexico. ... Uxmal is a large Pre-Columbian ruined city of the Maya civilization in the state of Yucatán, Mexico. ... Teotihuacan is the largest Pre-Columbian archeological site in the Americas. ... This article is about the Native American city. ...

Some artifacts that throw light on archaeoastronomy

• Ancient calendars based on astronomical observations
• Antikythera mechanism
• Nebra skydisk

Astronomy is one of the few sciences where amateurs can still play an active role, especially in the discovery and monitoring of transient phenomena. ... The Antikythera mechanism is an ancient artifact believed to be an early clockwork mechanism. ... The Nebra skydisk before restoration Diagram of the disk in its current condition (a star and a part of the full moon was restored). ...

Reference

• Clive Ruggles, Astronomy in Prehistoric Britain and Ireland

External links

• Mesoamerican Archaeoastronomy (http://www.jqjacobs.net/mesoamerica/meso_astro.html), a Review of Contemporary Understandings of Prehispanic Astronomic Knowledge.
• Archaeogeodesy (http://www.jqjacobs.net/astro/aegeo.html), the area of study encompassing prehistoric and ancient place determination, point positioning, navigation (on land or water), astronomy and measure and representation of the earth.
• Epoch 2000 (http://www.jqjacobs.net/astro/epoch_2000.html), an Excel spreadsheet for calculating temporally variable astronomic constants.
• Clives Ruggles webpage: (http://www.le.ac.uk/archaeology/rug/index.html) bibliography and synopsis of his course at Leicester University
• ISAAC (http://www.wam.umd.edu/~tlaloc/archastro/index.html), The International Society for Archaeoastronomy and Astronomy in Culture.
• Babylonian and Indian astronomy (http://uk.arxiv.org/abs/physics/0301078)
• International Institute of Astroarchaeology (http://www.astroarchaeology.org/)