Well, yes I realize that however astrology and astronomy existed at the same time. Astrology was a part of the teachings of astronomy. Astrology strictly dealt with what we still know it as today...peoples horoscopes. Astronomy dealt with mathematics in order for those of the day to be able to calculate holy days, navigation at sea and such. Copernicus learned this stuff very early on in history from books written in 1220 by Johannes de Sacrobosco.
Many early astronomers and mathematicians apply their skills to astrology to make a living, and it is, in fact, that field that led to the detailed observations of celestial objects. So even though it is apparent now that it's not science, it is a major contributor as a precursor to astronomy, much like how alchemy is the precursor to modern chemistry.
