This scientific leap of the imagination is something quite astounding, particularly given the times in which this leap was made.
On the left you can see the Earth rotating within a comparatively small-diameter Earth-centered celestial sphere.
Illustrated here are the stars (white), the ecliptic (red), and lines of right ascension and declination (green) of the equatorial coordinate system.
First Image Credit Flickr User Jaci XIII
Earth within ccelestial sphere - Wikimedia