BİRİNCİ FEN · ÜÇÜNCÜ BÂB · DOKUZUNCU FASIL · İkinci Madde
Article Two
It is reported that the ease of new astronomical rules and their methods have been written down.
O, esteemed one! Know that the new astronomers have said:
Initially, this brilliant sun was positioned as a fixed star at the center of the universe, in the middle, surrounded and immovably placed. Following it is the star Mercury, close to the sun and revolving around it. It has been observed that Mercury, upon its orbit, completes its revolution around the sun in three months. After Mercury comes the orbit of Venus, which completes its own revolution in eight months.
Following this, the existence of a wide circle encompassing Venus has been proven.
The Earth, surrounded by layers of water and air, is observed to traverse this aforementioned wide circle like a star in one year, along with these layers. It has been determined that the orbit of the Moon exists around the Earth upon the great and expansive orbit mentioned above. Indeed, the Moon also revolves around it, taking the Earth as its center, completing its revolution in one month.
Following this is the orbit of Mars, which encompasses the large terrestrial orbit. It has been ascertained that the star Mars completes its own orbit in approximately two years. Following the orbit of Mars is the orbit of Jupiter, which encircles it; it has been observed that the star Jupiter traverses its orbit only in twelve years. After the orbit of Jupiter comes the orbit of Saturn, which encompasses Jupiter’s orbit; it has been calculated that Saturn completes its own orbit in thirty years. Besides these stars, within the Earth's great orbit – as previously mentioned – just as the Moon revolves around the Earth taking the Earth as its center, five stars revolve around Jupiter and another five revolve around Saturn have been observed. These nine stars were observed by later astronomers, names were given to them, and they are called “little moons.”
Following all of this, it is known that in the sphere of constellations there exists a fixed star sphere encompassing all the orbits mentioned above. It is seen that its vast expanse is adorned with countless fixed stars. Each of these aforementioned fixed stars is of great solar size. It has been observed and determined that just as each of these fixed stars revolves around the sun, which is positioned at the center of the universe, illuminating the world, and exhibits the behavior and movements described above, so too do they exist in a rightful state. According to the view of those who hold this belief, the figures and circles drawn to depict the structure of the universe will be provided at the end of this section.