Nicolaus Copernicus wrote a book and called it “On the Revolutions of the Heavenly Spheres.” The Heavenly Spheres were the five known planets of his age. The word “planet” came from the ancient Greek word for “wanderer”, because these five planets appeared to wander about against the fixed background of the starry night. These wandering movements had for millennium puzzled and intrigued the minds of people. Copernicus added our Earth to the classification of planets and argued that it moved through the heavens like the other five wanders, and that they all traveled around the Sun.
Galileo was born 21 years after Copernicus died, and built upon the work of Nicolaus.
Copernicus wrote the book when he was around 40 years old. But because he anticipated that his ideas would be controversial, he delayed publication until just before his passing about 30 years later.
He didn’t seek to be controversial but merely sought a more elegant explanation for the truth of the observed universe. He sought Beauty. He built upon the ideas of predecessors, many of them out of the mainstream of contemporary thought.
His book is considered now to mark the beginning of the Scientific Revolution which has completely transformed our understanding of the world.
The Sun at center surrounded by 6 circles for the orbits of the 6 planets. (Copernicus assumed orbits were circular as did his predecessors. Later, the true ellipse shape of orbits was uncovered.)
Our Earth is shown in the third orbit at its 4 prime astronomical locations, Spring equinox, Summer solstice, Autumn equinox and Winter Solstice.
The two nearest planets, Mercury and Venus.
☿ Mercury occupies the innermost orbit.
♀ Venus occupies the second orbit from the Sun.
Our Earth occupies the third orbit from the Sun. It’s four prime orbital positions are illustrated on our banknote.
♂ Mars occupies the fourth orbit from the Sun.
Two of the four prime orbital positions of Earth are shown in the third orbit in this detail.
♃ Jupiter occupies the fifth orbit from the Sun.
♄ Saturn occupies the sixth orbit from the Sun.
Nicolai, you’re awesome.