Astrological synastry: the chemistry between two charts

Synastry is the branch of astrology that studies the relationship between two people by comparing their natal charts. It goes far beyond "Aries and Leo get along": it analyzes the aspects formed between the planets of both charts to reveal where there's chemistry, where there's tension, and where there's potential for growth.

How is a synastry done?

The two natal charts are taken and the planets are overlaid. Then the aspects between one chart's planets and the other's are calculated: your Sun with my Moon, my Venus with your Mars, your Mercury with my Jupiter, etc.

These aspects reveal the dynamic. For example:

• Sun-Moon harmonious: deep emotional understanding, "I get you without explaining".
• Venus-Mars in square: magnetic attraction with friction; intense passion.
• One's Saturn on the other's Sun: sense of weight, responsibility, restriction.
• Jupiter on Ascendant: the other expands you, makes you bigger, amuses you.

The 5 most important conjunctions in synastry

1. Sun conjunct Sun: shared identity, ease being together.
2. Moon conjunct Moon: deep emotional compatibility, "they speak the same emotional language".
3. Venus conjunct Mars: powerful physical and sexual attraction.
4. One's Sun on the other's Moon: feeling seen, understood, nurtured.
5. Ascendant conjunct Ascendant: immediate connection, comfort, feeling at home.

Tense aspects that are also important

A good relationship isn't only harmony. Tense aspects (squares, oppositions, quincunxes) generate attraction and growth. Two charts without any aspect between them tend to be indifferent. The most passionate couples have tense aspects resolved with consciousness.

The most common aspects in breakups:

• Saturn on Moon: emotional coldness, sense of being controlled.
• Pluto on Sun, Moon or Venus: intensity, jealousy, painful transformations.
• Chiron on Sun: hurting without meaning to; the other touches a deep wound.

Astrological scoring

Modern compatibility algorithms assign a 0-100 score based on:

• Sun-Sun compatibility (element and modality).
• Moon-Moon compatibility (emotional world).
• Venus-Mars compatibility (attraction and desire).
• Quantity and quality of harmonious aspects between the charts.
• Penalty for very tense unresolved aspects.

A score over 80 indicates a very fortunate connection; below 40, a relationship that will need conscious work.

Compare two natal charts

At Tu Verdad enter two people's data and get the cosmic affinity score, the breakdown by essences, emotional worlds, and attraction, plus the most relevant aspects. → Compare souls.