What Is Synastry?
Synastry is the art of comparing two birth charts to understand the nature of a relationship. When you overlay two charts and measure the angles (aspects) between one person's planets and another's, you reveal the energetic conversation happening between them — where they naturally harmonize, where they challenge each other to grow, and where deep soul-level threads connect them.
Below are 50 of the most significant synastry aspects, grouped by type. Each carries its own signature of attraction, dynamic, challenge, and long-term potential.
Conjunctions (☌)
Venus ☌ Mars
Raw magnetic attraction & desire
Venus ☌ Venus
Shared values & aesthetic resonance
Moon ☌ Moon
Deep emotional mirroring
Sun ☌ Sun
Shared identity & ego alignment
Mars ☌ Mars
Shared drive & passionate intensity
Venus ☌ Jupiter
Love, abundance & expansive joy
Moon ☌ Venus
Emotional warmth & affectionate bond
Sun ☌ Moon
Soulmate completeness & complementarity
Mars ☌ Pluto
Transformative power & intensity
Venus ☌ Pluto
Obsessive love & deep transformation
Trines (△)
Moon △ Sun
Emotional & identity harmony
Venus △ Mars
Effortless passion & attraction
Sun △ Moon
Warm, sustaining complementarity
Moon △ Moon
Flowing emotional understanding
Venus △ Venus
Shared relational values & ease
Jupiter △ Sun
Mutual expansion & optimism
Venus △ Jupiter
Love, luck & generous hearts
Mars △ Moon
Passionate care & active nurturing
Sun △ Jupiter
Inspiring confidence & shared vision
Moon △ Venus
Emotional tenderness & affection
Squares (□)
Mars □ Saturn
Frustrated drive & karmic growth
Venus □ Saturn
Love's hard lessons & commitment
Moon □ Saturn
Emotional restriction & maturation
Sun □ Moon
Identity vs. emotion tension
Mars □ Mars
Competitive friction & volatility
Saturn □ Moon
Emotional limitation & discipline
Venus □ Mars
Passionate tension & push-pull desire
Sun □ Saturn
Identity challenged by structure
Moon □ Mars
Emotional volatility & passionate friction
Saturn □ Sun
Authority meets ego in tension
Oppositions (☍)
Moon ☍ Sun
Magnetic polarity & completion
Venus ☍ Mars
Attraction through difference
Sun ☍ Saturn
Freedom vs. responsibility
Mars ☍ Mars
Direct confrontation of desire
Moon ☍ Moon
Emotional polarity & growth
Jupiter ☍ Saturn
Expansion vs. contraction
Venus ☍ Venus
Different love languages in tension
Sun ☍ Pluto
Power dynamics & transformation
Mars ☍ Saturn
Drive confronts restraint
Moon ☍ Saturn
Emotional need vs. duty
Sextiles (⚹)
Karmic & Special Contacts
Synastry FAQ
What is synastry in astrology?
Synastry is the branch of astrology that compares two people's birth charts to understand the nature of their relationship — romantic, platonic, professional, or familial. When you overlay two charts and study the angles (aspects) between planets, you can see where there is natural harmony, creative tension, deep attraction, or karmic complexity.
What are the most important synastry aspects for romantic compatibility?
The most significant romantic synastry aspects include Sun-Moon contacts (especially conjunctions and trines), Venus-Mars aspects for physical chemistry, Moon-Moon contacts for emotional resonance, and Venus-Venus contacts for shared values. Saturn aspects indicate long-term potential, while Pluto and North Node contacts often signal karmic depth.
Are challenging synastry aspects (squares, oppositions) bad for relationships?
Not at all. Challenging aspects create the dynamic tension that drives growth, passion, and transformation in relationships. Many of the most enduring and powerful partnerships have significant square and opposition aspects between their charts. The key is whether both partners are willing to engage consciously with the friction these aspects create.
What is the difference between synastry and composite charts?
Synastry compares two individuals' natal charts by overlaying them and examining how one person's planets interact with the other's. A composite chart creates a single chart by finding the midpoints between each person's planets — it represents the relationship itself as an entity. Both techniques offer valuable insights and are typically used together.