The Copernican Model

350 BCE

Aristotle sets Earth at the center of the universe.

270 BCE

Aristarchus suggests a sun-centered (heliocentric) universe with distant stars.

150 CE

Ptolemy publicizes the Almagest.

Thomas Digges

proposes modifying the Copernican system by removing its outer edge and replacing it with a star-filled unbound space.

1605

Johannes Kepler uncovers that orbits are elliptical.

1610

Galileo Galilei strengthened the heliocentric perspective by discovering Jupiter's moons and Venus's phases.

Nicolaus Copernicus

In 1473, he was born in Torun, Poland.

University of Kraków

From 1491 to 1495, Copernicus learned astronomy, philosophy, and mathematics at the ______.

University of Bologna

From 1496 to 1497, Copernicus studied astronomy and canon law at the *________* in Italy.

Frombork, Poland

In 1497, Copernicus was established as canon of the cathedral in_______.

University of Padua

From 1501 to 1505, Copernicus studied Medicine, Greek, and Law at the ________.

sun-centered

By 1508, Copernicus had begun to formulate his _____ universe model.

Commentariolus

In 1514, Copernicus published ________.

De revolutionibus orbium coelestium

In 1543, Copernicus’s _______ is published.

stationary point

According to Aristotle and Ptolemy, the Earth was a _____ at the center of the universe, surrounded by everything else.

Aristotelian Geocentricsm

According to the ______, each of the planets was contained within an invisible concentric sphere that rotated around Earth at a constant speed.

Aristotelian model

In Ptolemy's revision of the _____________, the planets were not attached to the concentric spheres by themselves but rather to circles that were connected to them — the epicycles.

Aristarchus of Samos

In 250 CBE, he first raised the possibility that Earth might revolve around the sun.

lack of stellar parallax

However, proponents of geocentrism have also long claimed that the "__________" is a scientifically sound argument against the validity of Aristotelian theories.

lunar sphere

Copernicus also proposed that Earth is located at the center of the ______.

Johannes Kepler

Later, the work of ________ replaced the concept of circular orbits with that of elliptical orbits, thereby eradicating the majority of the remaining flaws in Copernicus's model.