# Composite Chart

The sign of Gemini in the view of Johfra Bosschart

Synonym: Midpoint composite chart

A chart based on the combined birth data of two people – not to be confused with a Davison Relationship Chart. As with the latter, computers ease the task of calculating the horoscope and discerning the main themes of the relationship.

## Calculation

Midpoints are calculated based on taking the two natal charts of the people involved and halving the total sums – based on the smallest angle between them. For example, if one partner has the Moon at 13 degrees Taurus and the other at 27 degrees Aquarius, then the smallest angle between the two is 76 degrees. The composite Moon is located at the midpoint of 5 degrees Aries. The same method is used to calculate the position of all the other planets, the Moon's Nodes, and the MC and Asc. The house cusps can be taken from a table of houses based on the positions of the composite MC and Asc positions already calculated; a task simplified today by computer programs. An alternative way to calculate the Ascendant is to take the median time of birth at the place of birth – a method which can only be applied if the individuals were born at the same place.

## Interpretation

The midpoint composite chart, like the Davison Relationship Chart, is a conceptual or abstract chart. Composite midpoints can give planetary positions that would be impossible in reality. For example, it is possible for composite Mercury to stand in opposition to the sun although these two planets in reality can never be separated by more than 28 degrees (see elongation.) Nevertheless, many astrologers believe that composite charts have interpretive value and that transits to composite planets will affect the relationship. The Davison chart, in contrast, is based upon averaging actual times and geographical positions, thus giving a more realistic picture of the heavens, but it can locate the relationship in a geographically unlikely place, such as on the high seas or in the midst of a polar ice cap.

Astrologers disagree on the merit of one type of chart over the other. Critics of the composite chart suggest that it reveals the energy present at the start of a relationship whereas the Davison chart shows the deeper aspects of the relationship. The German astrologer Mona Riegger argues that "the composite chart equates to seventh house themes, whereas the Davison Relationship chart is more a reflection of the eighth house. The composite describes the phase of discovery and the Davison Relationship chart that of stabilisation." And further: "A composite horoscope can give us insights into many different kinds of human interaction, whereas I would only use a Davison Relationship chart when looking at relationships in which there is a deeper sense of commitment."[1]

The midpoint composite chart, or simple synastry comparisons, however, are favored in the writings of prominent American astrologers.[2]

The composite chart is read as the chart of a couple (or other type of relationship, perhaps of a parent and child or employee and employer.) The sun by its house and sign indicates the purpose or identity of the relationship. The ascendant shows how the pair appear to the outside world. Harmonious aspects indicate areas of the relationship that are likely to flow smoothly; whereas disharmonious aspects can show trouble spots and tensions.