Astrology consists of several pseudoscientific systems of divination based on the premise that there is a relationship between astronomical phenomena and events in the human world. Many cultures have attached importance to astronomical events, and the Indians, Chinese, and Mayans developed elaborate systems for predicting terrestrial events from celestial observations. In the West, astrology most often consists of a system of horoscopes purporting to explain aspects of a person's personality and predict future events in their life based on the positions of the sun, moon, and other celestial objects at the time of their birth. The majority of professional astrologers rely on such systems.
In one study, participating astrologers attempting to match natal charts with profiles generated by a psychological inventory produced results not significantly at variance with random chance.