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  2. Almagest - Wikipedia

    en.wikipedia.org/wiki/Almagest

    Ptolemy explains Hipparchus' discovery of the precession of the equinoxes and begins explaining the theory of epicycles. Books IV and V cover the motion of the Moon, lunar parallax, the motion of the lunar apogee, and the sizes and distances of the Sun and Moon relative to the Earth. Book VI covers solar and lunar eclipses.

  3. Equant - Wikipedia

    en.wikipedia.org/wiki/Equant

    The basic elements of Ptolemaic astronomy, showing a planet on an epicycle (smaller dashed circle), a deferent (larger dashed circle), the eccentric (×) and an equant (•). Equant (or punctum aequans) is a mathematical concept developed by Claudius Ptolemy in the 2nd century AD to account for the observed motion of the planets. The equant is ...

  4. Evection - Wikipedia

    en.wikipedia.org/wiki/Evection

    In astronomy, evection (Latin for "carrying away") is the largest inequality produced by the action of the Sun in the monthly revolution of the Moon around the Earth.The evection, formerly called the moon's second anomaly, was approximately known in ancient times, and its discovery is attributed to Ptolemy. [1]

  5. Lunar theory - Wikipedia

    en.wikipedia.org/wiki/Lunar_theory

    Ptolemy's work the Almagest had wide and long-lasting acceptance and influence for over a millennium. He gave a geometrical lunar theory that improved on that of Hipparchus by providing for a second inequality of the Moon's motion, using a device that made the apparent apogee oscillate a little – prosneusis of the epicycle.

  6. Timeline of astronomy - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_astronomy

    Al-Juzjani even proposed a solution to the problem. In al-Andalus, the anonymous work al-Istidrak ala Batlamyus (meaning "Recapitulation regarding Ptolemy"), included a list of objections to the Ptolemic astronomy. One of the most important works in the period was Al-Shukuk ala Batlamyus ("Doubts on Ptolemy"). In this, the author summed up the ...

  7. Celestial spheres - Wikipedia

    en.wikipedia.org/wiki/Celestial_spheres

    In Greek antiquity the ideas of celestial spheres and rings first appeared in the cosmology of Anaximander in the early 6th century BC. [7] In his cosmology both the Sun and Moon are circular open vents in tubular rings of fire enclosed in tubes of condensed air; these rings constitute the rims of rotating chariot-like wheels pivoting on the Earth at their centre.

  8. Deferent and epicycle - Wikipedia

    en.wikipedia.org/wiki/Deferent_and_epicycle

    Reason is employed in another way, not as furnishing a sufficient proof of a principle, but as confirming an already established principle, by showing the congruity of its results, as in astronomy the theory of eccentrics and epicycles is considered as established, because thereby the sensible appearances of the heavenly movements can be ...

  9. Timeline of cosmological theories - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_cosmological...

    Ptolemy emphasised that the epicycle motion does not apply to the Sun. His main contribution to the model was the equant points. He also re-arranged the heavenly spheres in a different order than Plato did (from Earth outward): Moon, Mercury, Venus, Sun, Mars, Jupiter, Saturn and fixed stars, following a long astrological tradition and the ...