Science - Timeline

Aristotle describes the geocentric (Earth-centred) model of the universe (350 BC)

Aristarchus proposes a heliocentric (Sun-centred) model of the universe (250 BC)

Ferdinand Magellan was the first European to observe the Magellanic Clouds later known as other galaxies (1520)

Nicholas Copernicus published paper that presents a heliocentric model with improvements to Aristarchuses (1543)

Kelper published Astronomia Nova which explained the motion of planets using the heliocentric model (1609)

Galileo publishes Dialogue on Two World Systems which argues the heliocentric model (1632)

Thomas Wright suggested the Milky Way is a flattened disk of stars and other nebulae might be other galaxies (1750)

Ernst Opik demonstrates the Andromeda nebulae is outside the Milky Way (1922)

Georges Lemaitre proposed the Big Bang theory suggesting the universe began as a giant explosion (1927)

Edwin Hubble discovers evidence of an expanding universe supporting the Big Bang theory (1929)