Astrology Relationship Analysis (Synastry)

Synastry is the process of comparing the astrology birth charts of two individuals to make an educated guess about how well they will get along in a romantic relationship. It is a fascinating and illuminating study of how individuals interact with one another. Most books on synastry focus on the aspects formed between the Sun, the Moon, and the planets in one chart to the other.


The synastry charts of any two individuals can be compared: business partners, parent/child, friends, enemies or whatever. Our purpose here, however, will be limited to the comparison of partners in a romantic or potentially romantic relationship. The synastry of love relationships. Each individual is born with a personal birth chart, which is a map of the heavens for the moment they took their first breath.

Some might say the birth chart has the effect of stamping, or imprinting, the energies of the planets and signs on an individual. Each and every one of us has all 10 planets and luminaries in our charts, but their positions by sign, house, and aspect are individual to each. When we interact with others, the individual energies of our natal charts form special relationships with their individual energies.

The resulting interplay is as complex and unique as our own personalities. The zodiac is made up of 12 signs. Each of these signs represents 30 degrees of the full astrological circle. Every individual has all the ten planets in his or her horoscope; the Sun, the Moon, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.

So it has to follow that these bodies are situated in the astrology birth chart in one or another of the twelve signs as well as one of the twelve houses. Which sign and which house depends on the exact moment of birth and where the birth occurred. You may call yourself an Aries or a Taurus, but that only makes reference to which sign the Sun was in when you were born.

The Moon and other planets were probably in other signs and houses scattered around the astrology chart circle. The twelve signs, twelve houses and ten planets are the basic components of the astrology chart. In synastry, we compare the relative positions of the planets and the houses between your astrology chart and the chart of another. It's that simple; and that complicated.

Sun Signs: Astrologers are frequently asked "Which Sun sign is best for me?" The short answer is, there is no short answer. There are too many other variables to consider to charge off looking strictly for someone born while the Sun was in this sign or that. Sun sign compatibility ranks low on my list of factors to focus on when seriously studying synastry. The Sun is about ego and individuality. It is important because it discloses those inborn traits that are not likely to change very much in an individual. No matter what our personality is like, these inborn traits are going to be there and be very apparent. Nonetheless, the Sun sign, which is often the only focus in relationships, is just a bit part in a complete analysis. This said, the often given advise about Sun signs will be repeated here.

The Sun signs fall into four groupings according the elements. Aries, Leo and Sagittarius are the fire signs; Taurus, Virgo and Capricorn are the earth signs; Gemini, Libra and Aquarius are the air signs; and, Cancer, Scorpio and Pisces are the water signs. There is tendency toward affinity within the elements. Each sign gets on somewhat better with other signs in its element. Further, the air and fire groups share more compatibility with one another, as do the earth and water Suns.

The predominate element matches: The elements are indeed important when evaluating a potential relationship. But the Sun sign is only one indicator of which element will be strongest in an individual. Each of the planets is in one or another of the signs, and often the planets out weigh the Sun in importance. By this I mean if the Sun is in a water sign, but most of the other planets are in fire signs, you may actually be more of a fire sign person. The Sun is an important indicator of the element that will be strongest in an individual, but it is not the absolute indicator. You will find significant compatibility with persons having a predominance in the same element as yourself. If your partner is not of the same element as yourself, you must become familiar and tolerant of the differences that should be expected.

The Moon's important role: The Moon has a lot to do with relationships because this luminary denotes the state of emotions and conditioned responses. If the Moon in one chart is square or opposed to the Moon in the partner's chart, chances are there have been some conflicting ideas existing based on backgrounds and previous experiences. A Moon in conjunction with the Sun of the partner is a very good sign in that the Moon person has a wonderful emotional connection with the ego of partner. A favorable Sun/Moon aspect, that is a conjunction, sextile, or trine, can largely smooth out a relationship. Indeed, the relationship between the Sun in the male's chart and the Moon in the female's chart may be even more important than the Sun to Sun relationship, as well as vice versa.

Mars and Venus: Mars and Venus play major roles in romance and in the mating process. Mars relates to your romantic desires; lust, if you will. It determines how sexually aggressive you are, and the raw passion, or lack of it, in your nature. Thus, Mars takes on the role of pursuit. This is why the symbol of Mars is also the symbol for the male. Venus, on the other hand, relates to the way in which you attract a mate. It represents the softer side of love; romance and emotional response to love. This role of attracting a mate links the sign of Venus with the female. The interaction of the two say a great deal about the chemistry between two people. They are often responsible for the sense of "love at first sight" and what would be called a very strong sexual attraction. Regrettably, love at first sight and a very strong sexual attraction doesn't necessarily make a long and durable relationship. Other factors will be more instrumental in determining this. Nonetheless, a good fit between Mars and Venus adds a wonderful dimension to your relationship. The most auspicious fit here between the partners would be for Mars and Venus to be in the same sign or in the same element. The attachment is much stronger if the planets form a conjunction or trine aspect.

The Aspects: The aspects formed between the Sun, the Moon, and the planets in one chart and the Sun, the Moon, and the planets in the partner's (or potential partner's) chart show the detail of how smoothly this relationship will work. Note that virtually every comparison will present some harmonious and some not so harmonious aspects. Don't expect anything else. Very seldom does the "perfect" match occur. By the same token, if nothing but negative aspects appear, such as “Squares” and “Oppositions”, then relationship is apt to be a major struggle.