The calculations are the same with every planet. Each sign has 30 degrees. So planets in Aries would be 0-29 degrees, Taurus 30-59 degrees, Gemini 60-89 degrees, etc. Add the degrees together of both planets such as Sun, Mercury, Moon, etc., then divide by 2 to find the midpoint. Then, do the same for the Ascendant and Midheaven to find the composite Asc. and MH. Then, just place the planets into the "new" chart that was made by the composite Asc. and MH. Interpretation is very similar except keeping in mind that this is a new *entity* (a relationship) instead of a single person. Hope that made sense.
