Astrology

Astrology was the belief that the relative position of planets and other celestial bodies could be used to predict the future. In particular, it was used to forecast the futures of individuals, based upon the predominant character traits of people born within certain date ranges. A person who could produce predictions based upon the underlying theories of astrology was called an astrologer. It was a common Earth practice in the Middle Ages.

The concept of astrology dated back to the Dark Times and was shared by every species in the universe. (NSA: Beautiful Chaos) Astrology, therefore, was not unique to Earth, despite the fact that the Human practice of the discipline was entirely based on the Earth's relative position to heavenly bodies in its close proximity. Mr. Smith once revealed to Luke Smith that many planets, like Draconia, had a kind of astrology. (SJA: Secrets of the Stars)

In medieval Europe, among many other parts and eras of Earth's history, astrology was viewed as a science. Various monarchical regimes had "official" or "court" astrologers. Sarah Jane and the Doctor were opposed by such a person when they visited the Duchy of San Martino. (DW: The Masque of Mandragora)