astronomy

Pythagoras

First to propose a spherical Earth, using observations like North and South constellations and lunar eclipses.

Plato's Concept of Earth

Described Earth as a globe, equidistant from its center, and having perfect, eternal contributions.

Aristotle's Geocentric Universe

Proposed a geocentric model with a fixed spherical Earth at its center in "On the Heavens".

Eratosthenes

Accurately calculated the circumference of the Earth through non-scientific methods.

Geocentric Theorists

Scholars like Plato, Aristotle, Ptolemy, and Tycho Brahe who believed Earth was at the center of the universe.

Heliocentric Theorists

Proponents like Aristarchus, Copernicus, Galileo, and Kepler who placed the Sun at the center of the universe.

Eudoxus of Cnidus

Proposed 27 interconnected geocentric spheres.

Claudius Ptolemy's Model

Described Earth as spherical with fixed stars and independent moving planets.

Aristarchus of Samos

Estimated sizes and distances of the Sun and Moon compared to Earth.

Modern Astronomy Characteristics

Differentiated by quantitative observations and logical mathematical theories.

Copernicus' Heliocentric Theory

Proposed Earth is one of many planets, rotating and revolving around the Sun.

Tycho Brahe

Modified the geocentric model and made precise measurements of planets.

Galileo Galilei's Discoveries

Discovered sunspots, the rough surface of the Moon, and the four Galilean moons of Jupiter.

Kepler's First Law

States that the orbits of planets are ellipses with the Sun at one focus.

Kepler's Second Law

An imaginary line from the Sun to a planet sweeps equal areas in equal intervals.

Kepler's Third Law

The cube of the orbital radius of a planet is proportional to the square of its period of revolution.