Why was the change from a geocentric model to a heliocentric model considered a revolutionary idea?
For centuries, Church doctrine placed the earth at the center of creation. The position was observationallly “obvious” because clearly everything that could be seen in the heavens moved around the oberver’s position on earth. The heliocentric model flew in the face of the “obvious” and it falsified Biblical notions of our world as the center of creation. Anything which put Church dogma into question was a danger to the Church’s position as arbiter of all thought, so by extension, proved to be a very real danger to the well-being of the progenitors of such “heresies.
