Synastry: comparing two charts
Synastry is the astrology of relationships: laying two birth charts side by side to see how one person's planets connect with the other's. Here are the key things astrologers look at.
The full deep dive
What synastry is
In synastry, an astrologer places one person’s planets around the other person’s chart and looks at the aspects between them. Each connection describes part of the relationship: attraction, friendship, friction, growth.
Where to start
- Sun and Moon: one person’s Sun in harmony with the other’s Moon is a classic sign of feeling understood.
- Venus and Mars: contacts between these show attraction and chemistry.
- Mercury: shows how easily you talk and understand each other.
- Saturn: contacts with Saturn can add commitment and staying power, or feel heavy.
- Elements: sharing elements (or complementary ones, like Fire with Air) helps things flow. See Fire, Earth, Air and Water.
Without birth times
Even without birth times, you can compare Sun, Venus, Mars and usually Moon signs, which already says a lot. With birth times, the houses and Rising signs add depth.
Composite charts
Some astrologers also make a composite chart, a single chart for the relationship itself, built from the midpoints between the two people’s planets. It describes the relationship as its own living thing.
Sources and perspectives
- Sue Tompkins, Aspects in Astrology
- Stephen Arroyo, Astrology, Psychology and the Four Elements