I believe in both. I figure. God created the sky and stars and God created humans with the capacity to learn and understand. God also seems to like to send messages to his creations, what better than the sky? It is up to each person to find their messages. Some will find them in a church, some through music and some through art and some in the stars.
Also, the Bible was written by humans. They are supposedly inspired. Why couldn't astrologers of old have been inspired as well?
God didn't stop talking to humans when the last page in the bible was written---If you listen you can hear..sometimes you can hear with your eyes and heart through the beauty in nature including the sky. Also, children learn to draw and do pictures before they learn to read and write. Humans knew art and nature before they knew books and words. God surely wouldn't have dismissed their need to be enlightened in life.