What is Synastry?

What is Synastry?
Photo by Leah Newhouse
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Synastry is the art of comparing two birth charts to understand the dynamics of a relationship. In astrology, it reveals how two individuals connect on emotional, mental, and spiritual levels by analyzing planetary aspects, house overlays, and compatibility factors. Whether in love, friendship, or business, synastry helps uncover strengths, challenges, and karmic ties in relationships. This guide will break down the key elements of synastry and how to interpret them.

How to do a Synastry analysis

To analyze synastry, start by overlaying both charts to identify hard aspects. These interactions create dynamic interactions that are strongly experienced in relationships. Squares introduce stimulating challenges that encourage growth, while oppositions highlight contrasts that can generate both magnetism and complexity. Conjunctions amplify planetary influences, shaping key relational themes. Examining these aspects reveals the fundamental dynamics at play.

What the planets mean in Synastry

In synastry, the Sun shapes identity dynamics, while the Moon influences emotional responses. Mercury affects communication styles, and Venus governs love expression. Mars drives passion and motivation. The Ascendant/​Descendant (AC/​DC) axis highlights relational pull, while the Midheaven/​IC (MC/​IC) axis reflects public and private life balance. Jupiter expands experiences, and Saturn establishes stability. Uranus introduces unpredictability and change, Neptune enhances dreams or illusions, and Pluto deepens intensity and transformation.

Other compatibility analysis techniques

While synastry is a powerful tool for relationship analysis, it’s just one of many techniques in astrology. Composite charts merge two birth charts into a single chart, revealing the relationship’s overall purpose and dynamics. Davison charts use a midpoint approach to create a shared chart based on time and space. Progressions and transits show how a relationship evolves over time. By combining these methods, astrologers gain a deeper, more nuanced understanding of compatibility.

Synastry offers deep insight into relationship dynamics by analyzing planetary connections between two birth charts. It reveals how individuals interact, where harmony flows, and where challenges arise. While this article provides an overview, specific aspects shape each connection uniquely. Subsequent articles will explore these aspects in depth, helping you interpret your own relationships with greater clarity. Understanding synastry is a powerful step toward self-awareness and deeper connections.

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