Astrology the ultimate kuffur....
The Messenger of Allah, peace and blessings be upon him, said, “Allah said: Among my servants are those who awaken with faith in me and disbelief in me. Whoever said we have been given rain due to the favor and mercy of Allah, he is a believer in me and a disbeliever in the stars. Whoever said we have been given rain due to the rising of this star, he has disbelieved in me and has put his faith in the stars.”
‘Some of My slaves entered the morning as My believers and some as unbelievers. He who said: We have had a rainfall due to the Blessing and Mercy of Allah, he is My believer and a disbeliever of stars, and who said: We have had a rainfall due to the rising of such and such (star) disbelieved Me and affirmed his faith in the stars.’” [Sahih Al-Bukhari and Muslim]