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  2. Planisphaerium - Wikipedia

    en.wikipedia.org/wiki/Planisphaerium

    The Planisphaerium is a work by Ptolemy. The title can be translated as "celestial plane" or "star chart". In this work Ptolemy explored the mathematics of mapping figures inscribed in the celestial sphere onto a plane by what is now known as stereographic projection. This method of projection preserves the properties of circles.

  3. 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]

  4. 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.

  5. Handy Tables - Wikipedia

    en.wikipedia.org/wiki/Handy_Tables

    Ptolemy's Handy Tables (Ancient Greek: πρόχειροι κανόνες, romanized: Procheiroi kanones) is a collection of astronomical tables that second century astronomer Ptolemy created after finishing the Almagest. The Handy Tables elaborated the astronomical tables of the Almagest and included usage instructions, but left out the ...

  6. 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 ...

  7. Deferent and epicycle - Wikipedia

    en.wikipedia.org/wiki/Deferent_and_epicycle

    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 (•). In both Hipparchian and Ptolemaic systems, the planets are assumed to move in a small circle called an epicycle , which in turn moves along a larger circle called a ...

  8. Category:Constellations listed by Ptolemy - Wikipedia

    en.wikipedia.org/wiki/Category:Constellations...

    Contributions; Talk; Category: Constellations listed by Ptolemy. ... Constellations listed by Greco-Roman astronomer Ptolemy (after 150 CE) — 48 are IAU recognized

  9. Canon of Kings - Wikipedia

    en.wikipedia.org/wiki/Canon_of_Kings

    The Canon of Kings was a dated list of kings used by ancient astronomers as a convenient means to date astronomical phenomena, such as eclipses.For a period, the Canon was preserved by the astronomer Claudius Ptolemy, and is thus known sometimes as Ptolemy's Canon.