Not only is the practice of astrology is haram, but also visiting an astrologer and listening to his predictions, buying books on astrology or reading one's horoscope are also forbidden. Since astrology is mainly used to predicting the future, those who practice it are considered fortunetellers. Consequently, one who seeks his horoscope comes under the ruling contained in the Prophet's statement, "The salah (daily prayer) of whoever approaches a fortune teller and asks him about anything will not be accepted for forty days and nights." [Sahih Muslim, vol. 4, p. 1211, no. 5440] The punishment in this hadith is simply for approaching the asking the astrologer, even if one is in doubt about the truth of his statements. If one is in doubt about the truth or falsehood of astrological information, he is in doubt about whether or not others know the unseen and the future besides Allah. This is a form of shirk because Allah clearly stated: "And with Him are the ke...