the classic mathematical observation of the sky derived from the teachings of Aristotle and the book Almagest by Ptolemy. It was the system most often used during the Medieval Era to explain the sky. It focused on a geocentric outlook that the Earth was the center of the universe and that the stars and planets were rotating spheres high above. This was useful to Christians as it left room for God and Hell outside of the star sphere. Created in the early 1st millennium, used throughout the medieval era until the days of Galileo. It was strongly voiced by Roman Catholic and contemporary authorities for a long time, and so it became a challenge for early astronomers to spread influence of their new ideas and discoveries. i dont know if its right or not
