Astrology has been embedded in the belief systems of different cultures around the world since antiquity. Beliefs in the effects of star constellations upon natural forces and upon human activities go so far as to influence the ways decisions are taken. A well-known astrological claim is that when Mercury is in retrograde, it affects people on earth, causing communication friction and difficulties.
Mercury Retrograde exploits the ability to access meta-data based on individuals’ internet activities in order to examine the validity of this belief. The analysis is based on twitter messages and compares the frequency of words reflecting communication problems between people and the ensuing emotional expressions of these problems.