What Does "Mercury in Retrograde" Mean?

You've probably heard the term 'Mercury in Retrograde," before, often used to explain bad luck or unexpected problems. But what does it really mean for Mercury to be in retrograde?

Sabrina Stierwalt, PhD
5-minute read
Episode #219

Image of Mercury from NASA's MESSENGER missionHave you ever been warned not to make any decisions this week because Mercury is in retrograde? Or perhaps you heard a friend blame a misunderstanding with their partner on the retrograde motion of our planetary neighbor? Maybe you have had a string of unusually bad luck—your car breaks down, a package gets lost in the mail, your wallet gets stolen, and then you see the shirt you just bought go on sale the very next day—and you’ve thought, ‘surely the universe is out to get me this week!’

Mercury began a period of what’s known as “retrograde motion” starting on December 19th and will continue to be in retrograde through the end of 2016. Some people look to the motions of the planets to explain a series of unlucky mishaps or a seemingly random failure in communication that would ordinarily have gone smoothly. Although astrology, the practice of linking terrestrial events to celestial observations, has long been popular, there appears to be a growing trend of increasing concern and attention paid to the retrograde motion of the planets in particular.

It is of course human nature to wonder in the face of such unexpected problems: Why is this happening to me now? Did I make a mistake or was this unpreventable? But should we really plan our life choices around the timing and motions of the planets? What does it really mean for Mercury to be in retrograde?

Mercury: the Planet of Communication

Since Mercury is one of the five classical planets, along with Venus, Mars, Jupiter, and Saturn, visible from Earth and thus known in ancient times, it’s hard to know who discovered Mercury. Being the closest planet to the Sun, Mercury spends a lot of time within the glare of our star’s light, and thus was likely the last of the classical planets to be seen. Some of the first accounts of Mercury date back to the Sumerians in the 2nd millennium BC, but its name comes from the Romans who named the planet after the messenger god since it was only visible for short periods of time.

Mercury is thus known to be the planet of communication, travel, and contracts. Thus, those who believe there is a connection between the planet’s motion and events here on Earth often avoid signing contracts, having important conversations, or taking a big trip when Mercury is in retrograde.  


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About the Author

Sabrina Stierwalt, PhD

Dr Sabrina Stierwalt earned a Ph.D. in Astronomy & Astrophysics from Cornell University and is now a Professor of Physics at Occidental College.