Astrology is a pseudo-science which claims that the positions of the heavenly bodies have an effect on the lives of human beings and events on Earth.

A long time ago, astronomy and astrology were the same. People studied the motions of the planets and hoped to used them to predict not only the behavior of the heavens, but also wars, natural disasters, the rise and fall of kings, and other earthly matters. However, around the time of Johannes Kepler, Galileo Galilei and Isaac Newton, astronomers came to realize these heavenly bodies had very little direct effect on Earth’s events. From that time on, the primary job of an astronomer was to use physics to understand what was going on in the sky, cementing the split between astronomy and astrology.

Be wary of referring to an astronomer as an astrologer!