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Claudius Ptolemaeus

Claudius Ptolemaeus

c. 100 CE–c. 170 CE · Alexandria

Claudius Ptolemy was a Greek-speaking astronomer, mathematician, and geographer of the 2nd century CE who worked at Alexandria. His astronomical treatise, known as the 'Almagest,' presented an Earth-centered model of the heavens that dominated science for over a thousand years, and his 'Geography' systematized the mapping of the known world using coordinates; he also wrote on optics, music, and astrology. His works were foundational for both the medieval Islamic and European scientific traditions.

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Did you know?

  • Ptolemy lived closer to the Moon landing than to the pyramids in his own country

    Claudius Ptolemy compiled his great star catalogue and his model of the heavens in Roman Alexandria, in Egypt, around 150 CE. Yet he lived roughly 2,700 years after the Great Pyramid was built and only about 1,800 years before the first Moon landing — closer in time to Apollo 11 than to the monuments standing in his own country.

    How we know

    Ptolemy active c. 150 CE (Almagest, Alexandria); Great Pyramid c. 2560 BCE; Apollo 11 = 1969 CE. To pyramid ≈ 2,710 yrs; to the Moon landing = 1,819 yrs; to 2026 ≈ 1,876 yrs — closer to Apollo 11 by ~890 yrs.

Life journeyclick any stop, or use ←/→

Stop 1 of 1

AlexandriaEgypt

We know they were here, but the specifics of what they did at this stop aren’t recorded yet in our corpus.

About Alexandria

Alexandria (al-Iskandariyya) is the great Mediterranean port-city of northern Egypt, founded by Alexander the Great in 331 BCE and a leading centre of learning in antiquity. After the Muslim conquest of Egypt (642) it remained a major commercial and scholarly hub; the Shadhili Sufi Ibn Ata Allah al-Iskandari (d. 1309) took his nisba from the city, and the modernist reformer Muhammad Abduh (d. 1905) was active in Egypt's intellectual life there and in Cairo.

In Alexandria at the same time

Aretaeus of Cappadocia, Dionysius Periegetes, Appian of Alexandria, Harpocration, Achilles Tatius, Apollonius Dyscolus

Across the traditions, in Alexandria at the same time

See other sages who lived in Alexandria→

In the same place & time

Sages whose lives overlapped with Claudius Ptolemaeus’s in the same cities, drawn from their recorded journeys.

Across the traditions

The world in their lifetime

Thinkers and teachers of other traditions whose lives overlapped with Claudius Ptolemaeus’s — a glimpse of the wider world they lived in. Drawn purely from recorded birth and death years.

Works(3)