History

Astronomy in ancient times

Astronomy in ancient times

Human curiosity about day and night, the Sun, the Moon and the stars, led primitive men to the conclusion that celestial bodies seem to move on a regular basis. The first utility of this observation was, therefore, to define time and to orient oneself.

Astronomy solved the immediate problems of the first civilizations: the need to establish precisely the right times for sowing and harvesting crops and for celebrations, and for the orientation of travel and travel.

For primitive peoples, heaven showed a very regular behavior. The Sun that separated the day from the night came out every morning from one direction, the East, moved evenly during the day and set in the opposite direction, the West. At night you could see thousands of stars following a similar trajectory.

In the temperate zones, they found that day and night did not last the same throughout the year. On long days, the sun rose more north and rose higher in the sky at noon. On days with longer nights the sun rose more to the south and did not rise so much.

Soon, the knowledge of the cyclic movements of the Sun, the Moon and the stars showed their usefulness for the prediction of phenomena such as the cycle of the seasons, on whose knowledge the survival of any human group depended. When the main activity was hunting, it was transcendental to predict the instant that the seasonal migration of the animals that served as food occurred and, later, when the first agricultural communities were born, it was essential to know the appropriate time to sow and collect the harvests

The alternation of day and night must have been a fact explained in an obvious way from the beginning by the presence or absence of the Sun in the sky and the day was surely the first universally used time unit.

It must also have been important from the beginning that the quality of night light depended on the phase of the Moon, and the twenty-nine to thirty-day cycle offers a convenient way to measure time. In this way the primitive calendars were almost always based on the cycle of the phases of the Moon. As for the stars, it must have been obvious to any observer that the stars are bright spots that retain a fixed scheme night after night.

The primitives naturally believed that the stars were fixed in a kind of vault on Earth. But the Sun and the Moon should not be included in it.

From the Megalithic stone engravings of the figures of certain constellations are conserved: the Big Dipper, the Little Dipper and the Pleiades. In them each star is represented by a circular socket carved into the stone.

From the end of the Neolithic we have reached menhirs and alignments of stones, most of them oriented towards the rising sun, although not exactly but always with a deviation of some degrees to the right. This fact suggests that they assumed the Polar Star fixed and ignored the precession of the equinoxes.

◄ PreviousNext ►
Prehistoric astronomy: magic, religion, science?Astronomy in ancient Europe