There is a common belief that if the D9 chart of Partner 1 is “similar” to the D1 chart of Partner 2 (meaning most planetary positions coincide), the couple has a strong potential for a long-term relationship, possibly leading to marriage and family life. However, this appears to apply only when there is mutual resonance (a kind of “cross-link” between the charts). If only one partner’s D9 overlaps with the other’s D1, while the second partner’s chart does not reflect this connection, the latter is likely to sense the imbalance and eventually slip away from the relationship.
Moon Compatibility
One of the most crucial indicators of compatibility is the relationship between the natal Moons of both partners.
If there is no harmony between their Moons – whether by sign or Nakshatra (constellation) – it indicates a connection lacking emotional balance and mutual sensitivity.
I would recommend Ilana Lib’s book “Nakshatras,” which offers excellent explanations of each Nakshatra and a clear matrix of relational dynamics between them. The interpretations in that work are consistently precise and aligned with real-life experiences.
Just like the Moon, the Ascendant sign also plays an important role – it is advisable to check compatibility by both sign and Nakshatra as well.
Sometimes, the Moon of Partner 1 may fall in the same sign or even the same Nakshatra as the Moon of Partner 2 – potentially indicating deep emotional understanding.
However, aspects and conjunctions with other planets can completely alter this picture.
For example, if one partner’s Moon is conjunct Mars in the same house – the Moon + Mars conjunction in anyone’s natal chart is a black flag. We will discuss this in greater detail later.
Common Problematic Configurations in Synastry Between Two Partners
Partner 1’s Moon + Partner 2’s Mars in the same sign or aspect
Drama, ugly quarrels, power struggles, emotional – and in some cases physical – wounds are just part of what to expect from such a connection. At first, there seems to be strong attraction, but the relationship quickly turns strange and unstable.
The Moon person – the more sensitive side – does not know how to cope with the aggressive attacks of the Mars person. Each outburst cuts like a knife from an unexpected direction.
Mars, being a malefic planet, seeks to control and exploit the Moon’s emotional vulnerability, violating dignity and personal boundaries at every opportunity.
There is no mutual understanding; their needs are completely different: the Moon person longs for tenderness and care, which Mars by nature cannot or does not wish to give due to his aggressive disposition.
Partner 1’s Venus 6–8 houses apart from Partner 2’s Mars
These are highly challenging relationships, full of appeasement, manipulation, and emotional dependency. This configuration can lead to abuse, toxicity, or even danger.
One partner may attempt to isolate and control the other’s life or conceal deceitful or harmful intentions (for instance, Venus in Sagittarius for Partner 1 and Mars in Cancer for Partner 2).
A few days after separation, the Venus person often feels immense relief, realizing they have escaped an “irritant” that they previously could not identify clearly due to emotional overload.
Partner 1’s Rahu/Ketu on Partner 2’s Moon (same sign)
This indicates a heavy karmic connection accompanied by emotional turbulence. Sometimes it is seen as a sign of possible marriage, though not always.
If they marry, they will find it hard to part; if not, the separation may be painful and lingering, even when it’s clearly for the best.