Astronomy as a science

Approximately contemporary with the megalithic cultures of western Europe, but flourishing independently of, were the much more advanced civilizations of Egypt, Babylon, India, and China. Each had its own system of astronomy, inextricably mixed with astrology, mythology, and religion. Each called upon the support of its own particular gods, kings, wise men, and mythical heroes to present its political, religious, or social aspirations to the people.
In Egypt, for example, astronomers made careful observations of the positions of the stars—especially the positions and times at which various stars rose and set. Of particular importance was the precise date of the summer helical rising (the emergence of a star from the light of the sun) of the bright star Sirius. This event portended the annual flooding of the Nile River, which was vital to the agricultural economy and hence, to the lives of the entire population of the Nile valley. The ancient Egyptian astronomers were also highly competent mathematicians—a skill that is apparent from the design (both external and internal) and positioning of the pyramids.

Middle-Eastern astronomers

In addition to the Nile River, the Tigris, Euphrates, and Indus rivers were also sites of flourishing civilizations in the 2,000 years before the birth of Christ. Their religious beliefs and cultures were incorporated into, and characterized by, their particular types of astrology and their special forms of mythology and folklore relating to the stars. Observations that may originally have had purely spiritual or religious purposes gradually became more scientific and thus encouraged the development of astronomy.
There were four main factors that enabled these ancient but advanced cultures to develop a relatively sophisticated astronomy: they were located in a part of the world that had clear skies throughout most of the year; they had a leisured elite with spare time to study the heavens; they had a written language, which provided them with a means of recording their observations; and they had the mathematical knowledge to make practical use of their astronomical findings. These favorable conditions were common to the civilizations of Babylon, Assyria, the Sumerians of Mesopotamia, the Egyptians at the time of the pyramids, the Greeks, and later, the Phoenicians and the Arabs.
In addition to using their knowledge of the heavens to make calendars and predict various regular events, these ancient civilizations also developed considerable skill in using the stars for finding directions. Consequently, they began navigating ships across the seas and caravans across the featureless deserts.
In Mesopotamia, however, in about the seventh century B.C., astronomy, and particularly the aspect of it known as cosmology (which concerns the universe as a whole) became closely involved with the Zoroastrian religion, which also devoted considerable attention to astrology, so that the two studies became linked. Later, Babylonian priests put astronomy back on a scientific and mathematical footing. But farther east it remained amalgamated with, and was often totally incorporated into, astrology.

The megalithic monument of Stonehenge (above) consists basically of several concentric circles of standing stones. The diagram deft) shows the positions of existing stones (solid black) and of the holes in which stones originally stood (outlined). There are many astronomically significant alignments among the various positions. The station stones (91 to 94) form an accurate rectangle, with the two short parallel sides indicating midwinter sunset (A) and midsummer sunrise
(B) (the latter also indicated by Stonehenge’s axis, center to Heel stone) and the two long sides showing the positions of moonrise (C) and moonset at major standstill. The diagonal (91 to 93) indicates moonset (E) and moonrise (F) at minor standstill. In addition, the moon undergoes an 18.61-year cycle in which its northernmost rising point moves between 50° north of east (major standstill) and 30° north of east (minor standstill).

A ziggurat, a large pyramidal stepped temple (a reconstruction of which is illustrated), was built in the center of most major Babylonian cities. Many ziggurats were dedicated to celestial gods—the one at Ur, for example, was dedicated to Su’en, the moon god. As in many other ancient civilizations, Babylonian astronomy was inextricably mixed with religion, mythology, and astrology. Moreover, the priests tended to be the best-educated sector of the population; thus they were largely responsible for the development of Babylonian science, including astronomy. The Babylonian empire lasted from about 2700 B.C to 500 B.C, during which time the priests did much to demystify astronomy and put it back on a scientific basis.


Despite modern science’s lack of regard for astrology, the work of the early astrologers was of great value in the development of astronomy, principally because of their accurate observations and records of star positions. But the conclusions that those astrologers drew from their observations depended far more on supernatural beliefs than on scientific principles. For example, from calculations known only to themselves, they plotted charts called horoscopes, from which they attempted to predict and influence future events.
Such interpretations of celestial phenomena were in accord with the belief. This belief was widely held in Europe before the discoveries of Copernicus and Galileo in the sixteenth and seventeenth centuries. It is still popular in many parts of the world today. As a result, in many parts of the world the astrologers themselves became extremely influential, consulted by the rich and the powerful. Astrology, therefore, became at best a pseudoscience occupied even obsessed with attempts to predict (and influence) the rise and fall of kings and governments and the course of national events.
Only the Hebrews, with their belief in one God whom they regarded as creator and arbiter of all things, strongly repudiated the views and claims of astrologers. Despite this, however, the Old Testament contains some 25 references to stars and astronomy.
Astrology also had an influence on the development of sciences other than astronomy. In early medicine, for example, each part of the human body was considered to be under the influence of a specific part of the celestial sphere. And alchemy, the embryo science of chemistry, adopted astrologers’ planetary symbols for various elements. For example, the planet Mars, named after the Roman god of war, gave its symbol to the metal iron.

Regarded as a whole, astrology can, therefore, be seen as an attempt to explain the apparently baffling mysteries of the natural world, not merely the celestial phenomena investigated by modern astronomers, and to establish a methodical interpretation of them. Although modern science now disagrees with astrology’s method, our understanding of the universe has benefited by its attempt to impose a logical order on natural phenomena.

An Egyptian mummy case showing the goddess Nut surrounded by signs of the zodiac. Despite the antiquity of this relic, which dates from the early A.D. 10ffs, many of the signs are the same as those used today; easily recognizable, for example, are Leo (the Lion), Libra (the Scales), Pisces (the Fish), Taurus (the Bull), and Gemini (the Twins).