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The Planets in Ancient Egypt  

Joachim Friedrich Quack

The five visible planets are certainly attested to in Egyptian sources from about 2000 bce. The three outer ones are religiously connected with the falcon-headed god Horus, Venus with his father Osiris, and Mercury with Seth, the brother and murderer of Osiris. Clear attestations of the planets are largely limited to decoration programs covering the whole night sky. There are a number of passages in religious texts where planets may be mentioned, but many of them are uncertain because the names given to the planets are for most of them not specific enough to exclude other interpretations. There may have been a few treatises giving a more detailed religious interpretation of the planets and their behavior, but they are badly preserved and hardly understandable in the details. In the Late Period, probably under Mesopotamian influence, the sequence of the planets as well as their religious associations could change; at least one source links Saturn with the Sun god, Mars with Miysis, Mercury with Thot, Venus with Horus, son of Isis, and Jupiter with Amun, arranging the planets with those considered negative in astrology first, separated from the positive ones by the vacillating Mercury. Late monuments depicting the zodiac place the planets in positions which are considered important in astrology, especially the houses or the place of maximum power (hypsoma; i.e., “exaltation”). Probably under Babylonian influence, in the Greco-Roman Period mathematical models for calculating the positions and phases of the planets arose. These were used for calculating horoscopes, of which a number in demotic Egyptian are attested. There are also astrological treatises (most still unpublished) in the Egyptian language which indicate the relevance of planets for forecasts, especially for the fate of individuals born under a certain constellation, but also for events important for the king and the country in general; they could be relevant also for enterprises begun at a certain date. There is some reception of supposedly or actually specific Egyptian planet sequences, names and religious associations in Greek sources.


The Planets in Aztec Culture  

Susan Milbrath

The Spanish chronicles do not mention planets other than Venus, although they compare certain Aztec gods with classical gods such as Jupiter and Mars. Creation myths recorded by the Spanish chroniclers frequently name Venus gods, most notably Ehecatl-Quetzalcoatl and Tlahuizcalpantecuhtli. The focus on Venus seen in these texts is also mirrored in colonial period Aztec codices, which feature several Venus gods as rulers of calendar periods associated with the 260-day calendar. The famous Aztec Calendar Stone represents Venus symbols prominently in an image showing the predicted demise of the Sun in an eternal solar eclipse, to be accompanied by earthquakes. Venus is apparently seen as the cause of a total solar eclipse in the Codex Borgia, a pre-conquest codex from Tlaxcala, a community neighboring the Aztecs in central Mexico. Although no pre-conquest Aztec codices survive, the painted screenfold books attributed to neighboring communities in central Mexico provide evidence of the kinds of almanacs that were probably also found in Preconquest Aztec screenfold books. The Codex Borgia has two Venus almanacs associated with heliacal rise events and another focusing on dates that coordinate with events involving Venus and possibly other planets. A unique narrative in the Codex Borgia traces Venus over the course of a year, representing different aspects of the synodical cycle. The transformation of Venus in the narrative is evidenced by subtle changes in the Venus god, Quetzalcoatl, who represents the planet Venus throughout the synodical cycle. Another god, Tlahuizcalpantecuhtli (“lord of dawn”), appears in the narrative associated with Venus as the morning star and also is represented in a death aspect during superior conjunction. This is in keeping with Aztec legends that tell how the Sun killed Tlahuizcalpantecuhtli with his solar rays. The Borgia narrative also helps identify Xolotl as the planet Mercury and provides hints about other planets that may be linked with different aspects of Tezcatlipoca, an Aztec god who ruled the night sky.


The Planets in Pawnee Culture  

Von Del Chamberlain

We can be certain that all cultures wondered about the Sun, Moon, planets, and stars, and that they found ways of incorporating what they observed into comprehension of themselves existing within their perceptible surroundings, both on earth and in the sky. Thanks to the gleanings of anthropologists in the late 1800s and early 1900s, we have a treasure trove revealing that the Native American Skidi Band of the Pawnee Nation possessed a unique creation tradition rich in astronomical symbolism. This includes the belief that the two bright planets encompassing within their orbits the orbit of planet Earth were considered by the Skidi to be the cosmic parents of the very first human child, a girl; the Sun and Moon were considered parents of the first male child. This story of human origin includes the legendary journey of the male Great Red Warrior from the east to court the Beautiful Bright White female star of the west, followed by the birth of their daughter transported to earth. This is a striking allegory of the apparent migrations of Mars and Venus, continually changing in brightness, undergoing retrograde motions and sometimes seeming to unite in close conjunctions. Watching these interrelations, repeated over and over with intriguing variations, likely led to and continually reinforced this tradition. Likewise, the apparent monthly relationships of Sun and Moon, with occasional eclipses, visually reinforced the account of the initial male human birth. Thus, the Skidi Pawnee tradition of human origins is an interesting, indeed beautiful, example of human interpretation of natural phenomena.


The Recognition of Meteorites and Ice Ages  

Alan E. Rubin

Two important scientific questions that confronted 18th- and 19th-century naturalists were whether continental glaciation had occurred thousands of years earlier and whether extraterrestrial rocks occasionally fell to Earth. Eventual recognition of these hypotheses as real phenomena resulted from initial reports by nonprofessionals, subsequent investigation by skeptical scientists, and vigorous debate. Evidence that kilometer-thick glaciers had once covered Northern Europe and Canada included (a) the resemblance of scratched and polished rocks near mountain glaciers to those located in unglaciated U-shaped valleys; (b) the similarity of poorly sorted rocks and debris within “drift deposits” (moraines) to the sediment load of glaciers; and (c) the discovery of freezing meltwater at the base of glaciers, hypothesized to facilitate their movement. Three main difficulties naturalists had with accepting the notion that rocks fell from the sky were that (a) meteorite falls are localized events, generally unwitnessed by professional scientists; (b) mixed in with reports of falling rocks were fabulous accounts of falling masses of blood, flesh, milk, gelatin, and other substances; and (c) the phenomenon of falling rocks could neither be predicted nor verified by experiment. Five advances leading to the acceptance of meteorites were (a) Ernst Chladni’s 1794 treatise linking meteors, fireballs, and falling rocks; (b) meteor observations conducted in 1798 showing the high altitudes and enormous velocities of their meteoroid progenitors; (c) a spate of several widely witnessed meteorite falls between 1794 and 1807 in Europe, India, and America; (d) chemical analyses of several meteorites by Edward Charles Howard in 1802, showing all contained nickel (which is rare in the Earth’s crust); and (e) the discoveries of four asteroids between 1801 and 1807, providing a plausible extraterrestrial source for meteorites.


Venus in Mesoamerica: Rain, Maize, Warfare, and Sacrifice  

Ivan Šprajc

During the last three millennia before the Spanish Conquest, the peoples living in the central and southern parts of modern Mexico and the northern part of Central America evolved into complex societies with a number of common characteristics that define the cultural area known as Mesoamerica and are expressed in technology, forms of subsistence, government, architecture, religion, and intellectual achievements, including sophisticated astronomical concepts. For the Aztecs, the Maya, and many other Mesoamerican societies, Venus was one of the most important celestial bodies. Not only were they aware that the brightest “star” appearing in certain periods in the pre-dawn sky was identical to the one that at other times was visible in the evening after sunset; they also acquired quite accurate knowledge about the regularities of the planet’s apparent motion. While Venus was assiduously observed and studied, it also inspired various beliefs, in which its morning and evening manifestations had different attributes. Relevant information is provided by archaeological data, prehispanic manuscripts, early Spanish reports, and ethnographically recorded myths that survive among modern communities as remnants of pre-Conquest tradition. The best-known is the malevolent aspect of the morning star, whose first appearances after inferior conjunction were believed to inflict harm on nature and humanity in a number of ways. However, the results of recent studies suggest that the prevalent significance of the morning star was of relatively late and foreign origin. The most important aspect of the symbolism of Venus was its conceptual association with rain and maize, in which the evening star had a prominent role. It has also been shown that these beliefs must have been motivated by some observational facts, particularly by the seasonality of evening star extremes, which approximately delimit the rainy season and the agricultural cycle in Mesoamerica. As revealed by different kinds of evidence, including architectural alignments to these phenomena, Venus was one of the celestial agents responsible for the timely arrival of rains, which conditioned a successful agricultural season. The planet also had an important place in the concepts concerning warfare and sacrifice, but this symbolism seems to have been derived from other ideas that characterize Mesoamerican religion. Human sacrifices were believed necessary for securing rain, agricultural fertility, and a proper functioning of the universe in general. Since the captives obtained in battles were the most common sacrificial victims, the military campaigns were religiously sanctioned, and the Venus-rain-maize associations became involved in sacrificial symbolism and warfare ritual. These ideas became a significant component of political ideology, fostered by rulers who exploited them to satisfy their personal ambitions and secular goals. In sum, the whole conceptual complex surrounding the planet Venus in Mesoamerica can be understood in the light of both observational facts and the specific socio-political context.