Copernicus published his astronomical model in 1543, he defended that the Sun was the center of the universe and the Earth with other planets would orbit around it in circular paths. The problem was that during that period scientists defended the geocentric system which defended that the center of the Universe was Earth. Scientists defended this model because the Church also defended it, mostly because it was compatible with the idea that Humans were made in the image of God and were the center of the Universe and the reason for its existence. Anyone that went against those thoughts was persecuted by the Church in the Inquisition.
