Muḥmmad-Karīm Khān Kirmānī (1810-1873) in his Riṣala fī Tazyīf Kitāb Afranjī fī Ḥarakāt al-Aflāk (A Treatise on a European Book’s Fraud about the Celestial Motions -April 10, 1853), brings an Arabic summary of a Persian translation of a European book. This summary includes heliocentrism as well as Cartesian and Newtonian mechanics to explain it, followed by Kirmānī’s detailed criticism. Based on the Aristotelian principles of space and movement, Kirmānī rejects the arguments of heliocentricity and its new mechanical explanations. In addition, he does not consider the empirical evidence sufficient to reject geocentrism. In his opinion, Cartesian and Newtonian explanations for heliocentrism are incompatible with the metaphysical principles of natural motion and the negation of vacuum. Kirmānī creates a change in the traditional concept of the orbs by changing the solidity of the heavens and accepting their rarity, to respond to heliocentric reasons. In addition, he believes that there is empirical evidence for denying the heliocentrism and mobility of the earth. He shows the flaws in the supporting experiments of the Earth's mobility. He even refers to the verses of the Qur'an. The philosophical-mystical system of Shaykhism was also a motivation to reject the new astronomy. Still, Kirmānī did not just emphasize his own belief system for his opposition to the new astronomy, as did many of his Christian Aristotelian counterparts in the 17th century.

Pre-modern astronomers often analyzed the longitudinal motion of the planets through the ecliptic, the path traced by the sun around the earth, in isolation from the motion of the planets in latitude to the north and south of the ecliptic. Although the models, i.e. configurations of orbs, for latitudes could be integrated into those for longitudes, astronomers presented them separately. Historians of astronomy in Islamic societies and in Jewish cultures, whether they study theoretical models or tables, have researched planetary longitudes much more than planetary latitudes. This imbalance may be because planetary latitudes did not have applications whereas longitudes had many.

In this presentation, I survey of the theories of Levi ben Gerson (1288-1344), a.k.a. Gersonides, for the motions of the planets in latitude. Levi was one of the most significant pre-modern Jewish scholars and has been judged to be the most creative pre-modern Jewish astronomer. Although Levi drew on the latitude theory of the Almagest, he also incorporated elements of the latitude models found in the Planetary Hypotheses into his own models.

Levi’s models for the planets’ motion in latitude are distinctive in that he transferred some of the building blocks of Ptolemy’s models from the Planetary Hypotheses to models from which epicycles were excluded. Levi’s latitude models are also distinctive because he theorized that one of the concentric orbs in the latitude models for Jupiter and Saturn revolved at twice the angular velocity of the other.

Athīr Dīn Abharī (d. 1265) was especially known as the author of philosophical works such as Īsāghūjī (Introduction to Aristotelian Logic) and Hidāyat al- Ḥikma (Summary of Aristotelian Philosophy). His scholarship was not limited to philosophy. He also wrote several books on mathematics and astronomy, including the largest extant astronomical work, Utmost Attainment in Comprehending the Orbs (Ghāyat al-idrāk fī dirāyat al-aflāk).

We notice that the Utmost Attainment has a section on the configuration of the cosmos (= ‘ilm al-hay’a), and besides the Utmost Attainment, he composed several works containing a section on the ‘ilm al-hay’a. Remarkably, it is known that Abharī learned astronomy under the supervision of Kamāl al-Dīn ibn Yūnus, a teacher of Naṣīr al-Dīn al-Ṭūsī on astronomy. This episode confirms that Abharī and Ṭūsī shared the same tradition of astronomical education, probably including topics concerning the ‘ilm al-hay’a

In this paper, I will elucidate Abharī’s version of the ‘ilm al-hay’a, which in turn I will reveal the standard frame of the ‘ilm al-hay’a around the time of Ṭūsī and the innovative aspect of the ‘ilm al-hay’a in the post-Avicennian period.