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Chart synthesis

Composite chart

The relationship as its own entity

The composite chart is constructed by taking the midpoint between each pair of corresponding planets in two natal charts. The result is a third chart that belongs to neither person — it belongs to the relationship itself.

Houses require both people to have known birth times. When either time is unknown, the composite shows planetary positions only.

Unlike synastry, which reads the tension and resonance between two separate charts, the composite describes what the two people become together: the shared purposes, the characteristic dynamics, the patterns that emerge only when both people are present.

Person A

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I know the precise birth time

Person B

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I know the precise birth time

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Astrian is in development. If you notice something that doesn't work as expected, we'd appreciate hearing about it at hello@astrian.app.