Synastry in Astrology

Synastry is the technique of overlaying two people's birth charts to analyze relationship compatibility. By examining how each person's planets fall in the other's houses and what aspects they form across charts, astrologers identify the dynamics of attraction, conflict, emotional resonance, and long-term compatibility.

How Synastry Works

Each person's planets are placed simultaneously on one chart wheel. The result reveals:

• Cross-aspects: How Planet A from Chart 1 angles to Planet B from Chart 2
• House overlays: Which house of Chart 1 a planet from Chart 2 falls in, revealing where that person impacts your life

The Most Significant Synastry Contacts

Sun–Moon aspects are the classic "soul mate" indicator — the Moon person feels emotionally nourished by the Sun person's core identity. Venus–Mars aspects create romantic and sexual magnetism. Ascendant–Descendant overlays often indicate that someone "looks like" exactly who you projected as your ideal partner.

Nodal connections — when one person's planets conjunct the other's North or South Node — signal karmic familiarity and fated meetings.

Saturn Contacts: The Glue and the Grind

Saturn synastry aspects are often the most stabilizing but also the most demanding. Saturn conjunct a personal planet can feel like commitment and responsibility — the Saturn person may seem like a reliable anchor, or like a limiting authority figure. Long-term relationships almost always have significant Saturn contacts.

Pluto and Transformation

Pluto contacts in synastry — especially Pluto conjunct Moon, Sun, or Venus — create obsessive pull and transformative power dynamics. These relationships change both people permanently, for better or worse.

Synastry vs. Composite Chart

Synastry reveals how two individuals interact; the composite chart (midpoint method) shows the relationship as its own entity — what this union is meant to become.

Related Terms

• Ascendant
• North Node
• Venus
• Mars
• Conjunction

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