Guides
Two sky maps, one conversation
Synastry compares two natal charts to read how two people relate. Ideal for anniversaries and couple gifts.
Synastry in one line
Synastry overlays two natal charts and studies the aspects between their planets: where they reinforce, where they tension, and what dynamic shows up between you.
It does not replace each individual chart. It is the bridge between them: a reading of the relationship.
Why it makes a strong gift
For anniversaries, weddings or engagements, synastry turns an object into a shared story: the day you met, or the crossing of your birth skies.
VisibleCharts couple layouts show both wheels and inter-chart aspects, ready as a print or PDF.
What it actually looks at
Synastry does not produce a score out of ten. It produces a list of contacts between two charts, and some carry far more weight than others. The ones that almost always say something: Sun with Moon, Venus with Mars, and any Saturn contact, which is the one that describes where a relationship asks for persistence rather than ease.
Beyond the aspects there is the house overlay: which area of one person's life each of the other's planets falls into. That is the difference between «we get on well» and «this person shows up in the territory of work, or of home, or of what you risk».
Inter-chart aspects are the only thing a couple chart has that a natal chart does not. So when an alternative wheel geometry cannot carry a bi-wheel, we do not offer it for synastry: two wheels without the lines crossing between them are two natal charts printed side by side.
What it is not
It is not a compatibility test. There are no «incompatible» charts, and anyone selling a percentage has invented a metric the technique does not contain.
Nor is it a forecast. Synastry describes a dynamic, not an outcome, and it works just as well for a twenty-year friendship or a mother and daughter as it does for a couple.
What you need
Birth date, time and place for each person. Time improves houses and Ascendant; if missing, say so in the configurator and review the preview before buying.
If only one of the two birth times is missing, the synastry still holds: the aspects between planets are unaffected. What is lost is that person's house overlay, which is one layer of the reading rather than all of it.
How we draw it
Two concentric wheels: the first chart inside, the second outside, aspect lines crossing between them. Names are printed on the piece unless you ask otherwise, and the certificate declares the coordinates and time zone of each person separately.
In the triptych the two natal charts flank the synastry, one on each side. It is the composition most often given at anniversaries, because it says three things at once: who each of you was, and what happens between you.
Is this the same as a composite chart?
No. Synastry compares two charts; a composite blends midpoints. We favour synastry because each person stays visible in the piece.
Does it work for friends or family?
Yes, and more often than you would think. The technique compares two charts, not two people in love. Mothers and daughters, siblings and lifelong friends account for about half the synastry orders we receive.
Can you make one for someone who has died?
Yes. All it needs is the birth date, time and place, and those do not expire.