Ptolemaic system
Geocentric celestial model
The Ptolemaic system is the model of the universe that placed Earth at the center, with the sun, moon, planets, and stars revolving around it in circular orbits.
Developed by the ancient Greek astronomer Ptolemy, it dominated Western astronomy for over a thousand years until replaced by the heliocentric model.
The term now suggests any outdated framework that puts the wrong thing at the center: His Ptolemaic view of the office had himself as the axis around which all decisions turned.
Orbits within orbits
- deferentShowing humble respect
- eccentricityUnconventional behavior or nature
- retrograde motionApparent reverse orbital path
- apogeeHighest orbital point
perigee · circular motion · planetary motion · longitude · latitude · calculation · prediction · trigonometry
Earth as cosmic hub
- universeComplete system or domain
- celestial spheresAncient cosmos's rotating layers
- heavensCelestial expanse overhead
- firmamentThe arching sky above
Egyptian Mediterranean port
- HellenisticOf post-Alexander Greek civilization
- antiquityGreat age, ancient era
- ancient astronomyEarly study of celestial bodies
- star catalogIndex of celestial objects
zodiac · ecliptic · astrolabe · armillary sphere · observations
Sun as orbital center
- GalileoRenaissance astronomer from Italy
- Tycho BraheRenaissance astronomical observer
- KeplerPlanetary motion law formulator
- paradigm shiftWholesale replacement of frameworks
scientific revolution · telescope · refuted · replaced · discredited
Of ancient systematic philosophy
- cosmologyStudy of universal structure
- natural philosophyHistorical term for science
- celestial harmonyOrdered beauty of heavens
- four elementsClassical natural categories
quintessence · aether · cosmic order · teleology · scholasticism
epicycles
Orbits within orbits
- deferentShowing humble respect
- eccentricityUnconventional behavior or nature
- retrograde motionApparent reverse orbital path
apogee · perigee · circular motion · planetary motion · longitude · latitude · calculation · prediction · trigonometry · parallax
geocentrism
Earth as cosmic hub
- universeComplete system or domain
- celestial spheresAncient cosmos's rotating layers
- heavensCelestial expanse overhead
firmament · cosmology · worldview · celestial realm · empyrean
Alexandria
Egyptian Mediterranean port
- HellenisticOf post-Alexander Greek civilization
- antiquityGreat age, ancient era
- ancient astronomyEarly study of celestial bodies
star catalog · zodiac · ecliptic · astrolabe · armillary sphere · observations
heliocentric
Sun as orbital center
- GalileoRenaissance astronomer from Italy
- Tycho BraheRenaissance astronomical observer
- KeplerPlanetary motion law formulator
paradigm shift · scientific revolution · telescope · refuted · replaced · discredited
Aristotelian
Of ancient systematic philosophy
- cosmologyStudy of universal structure
- natural philosophyHistorical term for science
- celestial harmonyOrdered beauty of heavens
four elements · quintessence · aether · cosmic order · teleology · scholasticism
- Astronomy HistoryCopernicus, Galileo, Kepler, Newton, Tycho Brahe
- Cosmologiesmultiverse, geocentric model, heliocentric model, expanding universe, cosmic egg
- Greek scienceAristotle, Archimedes, Euclid, Hippocrates, Galen
- ancient astronomyepicycles, stars, deferent, celestial sphere, geocentric
- Medieval Sciencealchemy, astrology, astronomy, natural philosophy, scholasticism
- Ptolemy's workgeocentric model, epicycles, star catalog, deferent, planetary motion
Ptolemaic systemheliocentrism
Sun-centered astronomical theory
heliocentric model · Newtonian mechanics · general relativity