Foundation of Modern Cosmology:
From Antiquity to ...

For everyone must see that astronomy compels the soul to look upwards and leads us from this world to another.
                                                            - Plato, Greek philosopher

The earliest investigations that can be called scientific are concerned with the sky: they are the beginnings of astronomy. It is this sense that astronomy rightfully claims the title of the "Oldest of the Sciences". Numerous early civilizations pursued the study of the heavens. Many produced astronomical texts, of which we have recovered a few fragments, but many more have left no written records. Most, however, have left us with monuments and artifacts - ranging from rock paintings to the Stonehenge - that show a clear interest in astronomy. Of the earlies civilizations, those of Ancient Egypt, China, Mesopotamia, the Indian subcontinent, and the Mayans had the most highly developed astronomies. There is growing evidence that many of these civilizations were in contact with each other and in some sense, knowledge and methodologies passed from one civilization to another over time.

Tracing the evolution of what we refer to as astronomy today, we find that the route passes first through the Greek civilization. Drawing from their upon the large body of observations and theories gradually gleaned from their older neighbors across the sea, Egypt and Babylonia, the Greeks continued the development of the field until the their decline. The mantle next fell upon the the medieval astronomers and philosophers of the Islamic Empires, who in turn preserved and enhanced the astronomy of the Euroasia civilizations, eventually passing the reigns onto Europe and to the likes of Copernicus, Tycho Brahe, etc. It is with Copernicus and Galileo that what we now know as Modern Astronomy was born.

Astronomy is the first truly global venture. Its realm is "heavenly", far removed from the profane earthly boundaries. It has been developed by all the civilizations of this world, both Eastern and Western. It is a triumph of the human intellect, of human civilization.

Let us consider the contributions of some of the early civilizations:

Our journey through the history of the science of astronomy begins in the Middle East, in the region known as the Fertile Crescent or Mesopotamia. This people who lived in this region are believed to have created the first "civilization" to have existed. Mesopotamians were the first to observe and describe complex patterns in the motions of the heavens. Using mathematical models to represent the patterns that they observed, they were able to predict the motions and positions of the sun, moon, and planets with excellent accuracy. By about 2700 years ago, they were able to predict lunar eclipses! They were able to develop accurate lunar and solar calendars and as we have already discussed previously, introduced the concept of constellations as a way to map the heavens. While the accomplishments of the Mesopotamian astronomers may seem trivial in comparison to what we know today or even the achievements of the latter civilizations, it is important to remember that their records and mathematical modeling represent the first scientific study of the heavens ever undertaken by mankind. In effect, the Mesopotamians created the scientific method.
Click on the sketch of the zigurat dedicated to the moon-god Nanna
in the city of Ur to find out more about the Mesopotamians
Bordering the Mesopotamians on the west was the Ancient Egyptian Civilization, another of the world's great early civilizations. The Egyptian or the Nile Valley civilization developed, as the name suggests, along the banks of the river Nile in Egypt. Its long, narrow flood plain was a magnet for life, attracting people, animals and plants to its banks, and providing ideal conditions for the development of stable communities. Like their neighbours, the Egyptians also studied the heavens, especially its cyclical patterns. The known oldest Pharaonic astronomical texts date back to the ninth Egyptian dynasty (c.2150BC). They give the names of thirty-six stars which rise within ten days of each other at the same time as the sun. Egyptian astronomers also seem to have recorded the appearance of Halley's comet some time in the period 1504-1450 BC. The course of stars and planets was also a preocupation of the Egyptians. There are indications that they considered the possibility of the earth moving about the sun. The early Egyptian solar calendar of 365 days, which was already in widespread use as early as 4200 BC, is the basis of our present calendar. In comparing the achievements of the Mesopotamians and the Egyptians, there is fair degree of uncertainty about who did what first and to what extent. What is clear is that the two empires shared a common boundary and therefore, it is inevitable that knowledge moved back and forth fluidly.
Click on the image of Sun God shining upon the Pharaoh and his Queen
to find out more about the Egyptians
To the east of Mesopotamia lay the Harappan Civilization, more commonly known as the Indus Valley Civilization. In common with other regions, nomads settled in the rich fertile valleys along the banks of the Indus River and the now-vanished Ghaggra-Hakra River or Sarasvati of the Rig Veda, a mighty river that at one time ran parallel and west of the Indus, in the fourth millenium B.C. By 2000 BC, they had established a thriving advanced civilization in in the western part of South Asia, in what today is Pakistan and western India. The Indus Valley civilization was the largest of the four ancient urban civilizations of Egypt, Mesopotamia, India and China. Like elsewhere, astronomy began as mere wonder at what was observed in the heavens above, grew into a systematic observation and speculation, hence forward into scientific inquiry and interpretation, finally emerging as a sophisticated discipline. At the same time, mystical interpretations of the movement of stars and planets developed into astrological science. Unfortunately, in spite of extensive excavation not much is known about this civilization because their script remains undeciphered. The civilization flourished for thousand years and then due to unknown reasons suddenly vanished from the face of earth around 1500 BC. Our primary source of of astronomy-related information are the Vedic texts, religious texts, that have been passed down largely through oral transmission. Details in this texts indicate a remarkably advanced civilization.
Click on the tablet showing what is believed to be a representation
of the Pleiades star cluster, also known as the seven sisters.
Further to the east was the Chinese Civilization. As in other cases, the civilization has its roots in nomads initially settling in the valleys and flood plains of the Yangzi and the Yellow Rivers. In time, these people began organizing and the earliest of the Chinese dynasties is now believed to have been the Xia ( (c. 2200 - c. 1750 BC) Until relatively recently, not much was known about these people and in fact, most historians thought that the dynasty was a myth. But the archeological record has shown otherwise, for the most part. What little is known indicates that the Xia had descended from a wide-spread Yellow River valley Neolithic culture known as the Longshan culture, famous for their black-lacquered pottery. Even though no known examples of Xia-era writing survive, they almost certainly had a writing system that was a precursor of the Shang dynasty's "oracle bones." Evidence from these Shang oracle bone inscriptions shows that at least by the 14th century BC, the Shang Chinese had established the solar year at 365 1/4 days and lunation at 29 1/2 days. In the calendar that the Shang used, the seasons of the year and the phases of the Moon were all supposedly accounted for.
Click on the picture of the Shang Oracle Bone
The Mayan Civilization is probably the best-known of the classical civilizations of Mesoamerica. Originating in the Yucatán around 2600 B.C., they rose to prominence around A.D. 200 in present-day southern Mexico, Guatemala, northern Belize and western Honduras. Building on the inherited inventions and ideas of earlier civilizations such as the Olmec, the Maya developed astronomy, calendrical systems and hieroglyphic writing. The Maya were noted as well for elaborate and highly decorated ceremonial architecture, including temple-pyramids, palaces and observatories, all built without metal tools. They were also skilled farmers, clearing large sections of tropical rain forest and, where groundwater was scarce, building sizeable underground reservoirs for the storage of rainwater. The Maya were equally skilled as weavers and potters, and cleared routes through jungles and swamps to foster extensive trade networks with distant peoples.

Of all the world's ancient calendar systems, the Maya and other Mesoamerican systems are the most complex, intricate and accurate. Calculations of the congruence of the 260-day and the 365-day Maya cycles is almost exactly equal to the actual solar year in the tropics, with only a 19-minute margin of error. Maya astronomer-priests looked to the heavens for guidance. They used observatories, shadow-casting devices, and observations of the horizon to trace the complex motions of the sun, the stars and planets in order to observe, calculate and record this information in their chronicles, or "codices". From these observations, the Maya developed calendars to keep track of celestial movements and the passage of time. The Maya also kept detailed records of the moon, although these do not seem to constitute a formal lunar calendar.

Click on the picture of the Mayan Calendar

Before continuing on, it should be noted that as impressive as the achievements of these civilizations are, it is not until we go beyond simply predicting the occurences of the cyclical behaviour of the celestial objects and start asking the question "how" that science comes into own. But these early civilizations certainly started us solidly down that path by providing us with enormous amounts of data about the cyclical patterns of the heavens. Much of what followed would not have been possible without the foundation laid by these early civilizations.