Synastry describes the techniques used to compare two charts. There are various techniques to analyse how two charts will react together. The most straightforward is that of direct chart comparison.
Direct Chart Comparison
How planets from Chart A aspect planets from Chart B
This gives a measure of the energy exchange between two charts. Some are more well thought of and easier to handle. For instance A’s Venus conjunct B’s Jupiter is probably easier to deal with than A’s Saturn on B’s Moon.
Where A’s planets fall in B’s chart
This gives an additional layer to planet to planet comparison. There will be an extra emphasis on chart areas which will be shown by examining this.
How the tone of the two charts compare
Less clear cut but an important factor. It’s not enough for two people to have fantastic Mercury connections if one chart is very cold and cerebral and the other is intuitive, artistic and creative. These people will be coming from very different places although they will have some understanding. As with everything, you need to consider the whole chart rather than just one point.
Charts for the relationship itself
There are also charts which can be drawn up to represent the relationship. You can use the event chart if this data is know, wedding chart if appropriate, the composite chart or the Davision relationship chart.
These charts represent the relationship itself rather than the energy dynamic between two individuals.
The composite chart takes the midpoint between a points in chart A and the same point in chart B to give the composite point. For example if A’s Sun is at 10 Aries and B’s Sun is at 10 Gemini then the composite Sun will be at 10 Taurus. There is no location for a composite chart. The angles are also derived from the two charts in question. These charts can receive transits but can’t be progressed as they don’t actually exist.
Points to note when judging these charts:
- You may get astronomically impossible configurations as the chart is hypothetical.
- Slower moving planets will be little different from the natal positions of people the same age. Likewise planets which are conjunct in chart comparisons.
- Composite charts exist for all possible relationships but this doesn’t mean that we’re going to have a relationship with that person.
The only composite chart with is in existence for the whole of a lifetime is the child’s end of the parental composite as it is activated when they are born.
Davison Relationship Chart
The midpoint in space and time between two individuals forms the basis for this chart. For instance if A was born on 1st September and B was born on 3rd then the Relationship would be born on 2nd. The point between locations forms the where.
As these charts do physically exist you don’t get the weird Sun Venus oppositions which a composite can throw up and they can be progressed.