Synastry Astrology: Mercury to Mercury

Astrology has many uses and techniques; one of the most popular uses is synastry, which is the term to describe how two charts interact with each other.  We all have the same points in our charts: the Sun in a sign, the Moon in a sign, Mercury in a sign, and so on.  When we get together with someone our energy designs (our charts) interact.

This article is one of a series to look at the interaction of points between two people and explain how to interpret the dynamics between the same point in different charts.  This article will look at Mercury, which rules communication.

What is Synastry Astrology?

It is probably easier to show it visually rather than write a lengthy explanation.  Below you will see a single image of two charts, one on the inside and another going around the outside.  There are two images to show what the relationship looks like when person A is on the inside and person B is on the outside, then the reverse.

Relationship Person A to B chart
Relationship Person B to A chart

These were randomly generated charts. As you can see all the same points appear in different signs throughout the two charts.  When we look at them together, we have the chance to see the kinds of energy dynamics that will take effect when they form a connection, whether as lovers, friends, or family members.

Reading the Synastry of Two People

A fair amount of my work as a professional astrologer involves relationship charts reading, and I always start with the Moons (the previous article); next, I choose to look at Mercury.  Often clients or people I meet in public, who find out I am an astrologer will say something like, “I am a Leo and read somewhere that I should never date a Scorpio” or “I am a Leo and should only date fire and air signs, like Aries or Gemini”.  Then they ask, “is that true?”

While it is true that the Sun sign is very important, when it comes to romance or any other emotionally charged relationship (like a friendship or with a family member), it is the Moon that plays the most significant role.  But even before I look at the Sun signs, I look at where Mercury is in each chart.  I chose Mercury second because this point determines how two people will communicate.

Please keep in mind that flowing energy is not the same as positive energy.  Flow occurs when two points aspect or align with each other in certain ways and close to the same degree.  For example, if I have my Mercury in Leo at 12 degrees and you have your Mercury in Aries at 13 degrees, our Mercuries will trine and easily flow since they are both in fire signs. 

That is great if we communicate well and positively with our fiery approach, but not so great if one or both of us chooses to be argumentative all the time, picking verbal fights constantly.  And no matter how problematic the communication energy between us, the flow will keep us communicating and trying to “win” our points on whether the relationship is healthy or not.

The Aspects to Consider

The most powerful aspects are the conjunction (in the same sign and near the same degree), the square (three signs apart, in conflicting elements, and near the same degree), and the opposition (in opposite signs, and balancing elements, and near the same degree).  Additionally, and worth discussing in a synastry reading is the trine (four signs apart, in the same element, and near the same degree), the sextile (two signs apart, in complementary elements, and near the same degree), and the inconjunct (five signs apart, in compromising elements, and near the same degree).

My Mercury to Your Mercury and Your Mercury to My Mercury

Below I have marked the Mercuries from the two charts:

Relationship A to B Mercury to Mercury

The Mercury for Person B is in Aries and the Mercury for Person A is in Scorpio.  They inconjunct each other by sign, but not degree.  To inconjunct by degree they would need to be within 3 degrees of the exact inconjunct and they are over 13 degrees apart. 

Orbs of Influence

Let me break the “4th Wall” for a moment and say that Astrology is not an exact science, or really a science in any rigorous, mechanistic Newtonian sense.  Some astrologers will give points a 6-degree orb; I prefer to use more points in the charts I cast; so, I use smaller orbs.  Hellenistic (classical) astrology would disregard the orbs of influence and just say they are inconjunct.  I do think proximity by degree matters, but I also use quite a large number of points (23 in the examples here) in my charts, so I prefer to tighten the orb of influence for all the points.

Since the Mercuries of these two people are inconjunct, they will struggle to maintain communication flow.  The Aries Mercury person prefers to communicate in a direct and honest way while the Scorpio Mercury person prefers to communicate in an intense, emotional way.

I like to describe the inconjunct as a carburetor, which was the mechanical device on a car engine that controlled the flow of fuel into the engine before fuel injectors became the control mechanism.  Carburetors, over time, would become less and less efficient and need “adjusting”.  The inconjunct aspect means the two points constantly need adjusting at some point and will constantly get out of sync.

Consider something as simple as going out to dinner.  Aries will prefer to initiate, and Scorpio may want to initiate or may want Aries to initiate.  Aries will start with many suggestions, but they all need to be ones the Aries would enjoy.  Scorpio wants to eat where it wants to eat and this will work fine so long as they agree, but if they do not agree, sparks can fly.  Even more problematic, Scorpio may “keep it a secret” and complain after they have gone somewhere together, which will bother Aries immensely.

This communication energy can work, but it will always be work.  If one of the individuals is living in the “shadow” of the sign, then the Aries will selfishly want to have dinner where they want to regardless of the feelings of others.  Scorpio will use any and all forms of communication as an endless opportunity to engage in a power struggle.

Finding your Mercury in your Chart

You can certainly contact me for a chart reading and I can give you a comprehensive reading of your entire chart and tell you where the Mercury is.  But you can also find it by going to an online ephemeris and looking up the Mercury by sign on the date and time of your birth. 

Keep in mind that the Mercury changes signs roughly every three weeks.  If you were born on the day Mercury changed signs, be sure to know what time the change happened to get the accurate sign of your Mercury.

Join me next month when we look at Sun to Sun and how you share life paths!

Philip Young, PhD

I am a spiritual adviser located in Cary, North Carolina. I earned my PhD in English from the University of North Carolina at Greensboro in 1996 and had a career in academics until 2007, when I retired to become a stay-at-home father. In 2013 I “hung out my shingle” starting my business Black Unykorn Enterprises, LLC. I provide spiritual guidance using different tools: astrology, tarot/oracle cards, numerology, and past life regression (using muscle testing). With a home office, Zoom, WeChat, and WhatsApp, I work with local clients in person and distance clients from around the world. You can read about my practice and contact me through my website: https://www.blackunykorn.com.

Related Articles