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  2. Almagest - Wikipedia

    en.wikipedia.org/wiki/Almagest

    An edition in Latin of the Almagestum in 1515. The Almagest (/ ˈ æ l m ə dʒ ɛ s t / AL-mə-jest) is a 2nd-century mathematical and astronomical treatise on the apparent motions of the stars and planetary paths, written by Claudius Ptolemy (c. AD 100 – c. 170) in Koine Greek. [1]

  3. Ptolemy's table of chords - Wikipedia

    en.wikipedia.org/wiki/Ptolemy's_table_of_chords

    The table of chords, created by the Greek astronomer, geometer, and geographer Ptolemy in Egypt during the 2nd century AD, is a trigonometric table in Book I, chapter 11 of Ptolemy's Almagest, [1] a treatise on mathematical astronomy. It is essentially equivalent to a table of values of the sine function.

  4. Ancient Greek astronomy - Wikipedia

    en.wikipedia.org/wiki/Ancient_Greek_astronomy

    Book 2 provides the basic results that one can arrive at with a spherical astronomy. Book 3 provides a theory of the sun. Book 4 provides an equivalent treatment for the moon. Book 5 deals with the new complications that arise from applying Ptolemy's theory to the moon, as opposed to the simpler case of the sun.

  5. 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 ...

  6. The Book of Fixed Stars - Wikipedia

    en.wikipedia.org/wiki/The_Book_of_Fixed_Stars

    The book was thoroughly illustrated along with observations and descriptions of the stars, their positions (copied from Ptolemy's Almagest with the longitudes increased by 12° 42' to account for the precession), their magnitudes (brightness) and their color. Notably, al-Sufi improved upon Ptolemy's system for measuring star brightness.

  7. Theon of Alexandria - Wikipedia

    en.wikipedia.org/wiki/Theon_of_Alexandria

    It originally consisted of 5 books, of which books 1–3 and the beginning of book 4 are extant. It describes how to use Ptolemy's tables and gives details on the reasoning behind the calculations. [1] Little Commentary on Ptolemy's Handy Tables. This work survives complete. It consists of one book and is intended as a primer for students. [1]

  8. Tetrabiblos - Wikipedia

    en.wikipedia.org/wiki/Tetrabiblos

    Opening chapter of the first printed edition of Ptolemy's Tetrabiblos, transcribed into Greek and Latin by Joachim Camerarius (Nuremberg, 1535).. The commonly known Greek and Latin titles (Tetrabiblos and Quadripartitum respectively), meaning 'four books', are traditional nicknames [24] for a work which in some Greek manuscripts is entitled Μαθηματικὴ τετράβιβλος ...

  9. Deferent and epicycle - Wikipedia

    en.wikipedia.org/wiki/Deferent_and_epicycle

    The angular rate at which the epicycle traveled was not constant unless he measured it from another point which is now called the equant (Ptolemy did not give it a name). It was the angular rate at which the deferent moved around the point midway between the equant and the Earth (the eccentric) that was constant; the epicycle center swept out ...