Of the obscurantism practiced by the ancient shamans and priests in their ancestral rites of superstition, sometimes mixed with the light of the careful and systematic observation, a vision emerges astronomical that is gradually leaving behind, although will never cease to do so in this period, its origins astrological to begin to found the foundations of a cosmological observation of the universe. In these times, it is the Greeks who breathe a new air to the history of humanity in all its meanings, social, religious and scientific. Your culture is ours, and his vision of the universe will accompany us until our days. The Romans, heirs of this culture, they will only serve as transmitters of it without contributing too many substantial advances.

seem to be more than two hundred treatises, even if only reached our thirty-one days of them. His theory was that of a spherical cosmos, of which the Earth was the center, which contained the four primal elements –Earth, air, fire and water– that formed the so-called sublunar world, which in turn was enveloped by a fifth element – called ether – that filled the entire universe, and constituted the super-lunar world. Likewise, Aristotle conceives for the first time the Earth as a spherical object, because your observations of the stars allow you to distinguish that they change their height on the horizon according to the position of the observer on Earth, which would not happen if it were an object flat. This form was also perceived in the eclipses of Moon when the shadow of a curved line was drawn on its surface.