Map projection with coordinates (Ptolemy's Geography)
Cartografía con proyección y coordenadas (Geografía de Ptolomeo)
- Date
- c. 150 CE · confidence high
- Place
- Alexandria, Egypt
- Credited to
- Claudius Ptolemy
- People
- 👤 Claudio Ptolomeo100–170
- Field
- Movement
What it is
A method for representing the spherical Earth on a plane using conic projections, with a list of 8,000 places with latitude and longitude. The foundation of mathematical cartography.
Ptolemy underestimated the Earth's circumference, following Posidonius, an error that persisted for 1,300 years.
What it led to
- Maps reproducible from numerical data rather than drawings
- The Renaissance rediscovery that spurred Columbus's voyages (with its underestimate of size)
- The concept of a grid of meridians and parallels used to this day
- Geography as a quantitative science
Built on
- Gnomon and graduated sundialc. 560 BCE
- Anaximander's world mapc. 550 BCE
- Sphericity of the Earthc. 350 BCE
- Euclidean axiomatic geometryc. 300 BCE
- Measurement of Earth's circumference (Eratosthenes)c. 240 BCE
- Strabo's Geographyc. 20 (obra de entre 7 BCE y 23)
- Eratosthenes's measurement of Earth's circumference
- Euclidean geometry
- Roman itineraries
Made possible
- Ptolemy's Geography and world coordinatesc. 150
- Tabula Peutingerianac. century IV (copia medieval del century XIII)
- Terrestrial globe1492
- Waldseemüller's Universalis Cosmographia (the name "America")1507
- Mercator projection1569
- Matteo Ricci's Kunyu Wanguo Quantu1602
- Renaissance maps
- Geographic coordinate system