What does «esfera celeste (círculos y coordenadas)» mean in Spanish?
- The profane observer contemplates the stars as adhering to an immense sphere whose center was himself and of which at any given moment he perceives only half, situated on the apparently horizontal and infinite surface of the Earth. The thousands of visible stars seem immobile in the sphere in question, and for this reason the legendary constellations, many of which were baptized in pre-Homeric times by men now forgotten, have not since changed appreciably in form. Our observer notices, on the other hand, how the Sun, the Moon and the planets seem to move slowly on the starry background (v. Planet).