What synastry is
Everyone has their own birth chart. In synastry the two are overlaid: one person's planets are read against the other person's planets and houses. There is no universal "compatible sign"; there is a specific dynamic between two specific charts.
What a synastry looks at
Aspects between the two charts
When one person's Sun makes an aspect to the other's Moon, or Venus touches Mars, a theme is born in the relationship. Trines and sextiles tend to bring ease; squares and oppositions bring attraction and friction at the same time. A relationship with no tension at all can be comfortable, but also static.
The houses where the other's planets fall
If your partner's planets fall in your 7th house, the relationship touches your partnership theme directly; in the 4th, it stirs your sense of home; in the 10th, your career and goals. That is why synastry is read both ways: what you awaken in the other is not always what they awaken in you.
The best-known contacts
- Sun and Moon: basic understanding and a sense of support.
- Venus and Mars: attraction, desire and rhythm.
- Mercury: how you talk and resolve disagreements.
- Saturn: commitment and responsibility, sometimes heavy.
Synastry and the composite chart
The composite chart is a different technique: instead of overlaying two charts, it calculates a third one from the midpoints between both people's planets. It is read as the chart of the relationship itself, as if it were an entity with its own identity and challenges.
How to do a synastry on Arkanova
- Open synastry and enter both people's birth details.
- See the bi-wheel: one chart inside, the other outside, each with its own houses.
- Read the aspects between the charts, in both directions, and the blocks and gifts each one activates in the other.
- Open the composite chart to see the relationship as a whole.
You can save your people in "My people", with or without an account.
Frequently asked questions
Does synastry say whether a relationship will work?
No. It shows dynamics, strengths and sensitive themes. The outcome depends on what both people do with them.
Do I need both birth times?
It helps a lot, because the houses depend on the time. Without it, the aspects between planets remain valid; the houses and the Ascendant become uncertain.
What is the difference between synastry and a composite chart?
Synastry compares two charts side by side. The composite merges them into one, calculated from midpoints, and describes the relationship itself.
Is it only for couples?
No. It works for any relationship: friends, parents and children, business partners or colleagues.
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