The Moon is as important as the Sun in your natal chart. The Sun sign is a part of you that is apparent to others; it is what others see. The Moon sign is the part of you that you see.
The Moon represents your emotional nature and instinctive reactions – emotional responses based on past experiences and unconscious habit patterns that you have developed. It comprises all the little surface peculiarities, moods, and changes that have to do with physical life which are disturbing, fleeting, and changing. The Moon rules Cancer and the Fourth House.
The Moon describes your immediate emotional responses. Have you ever done something that you thought, “that’s not like me.”? It may have been your Moon sign qualities at work. Your Moon shows what makes you feel emotionally nurtured, secure, and satisfied. Because emotions run so deep, the Moon sign represents your greatest need. It also shows how you nurture others.
Most of the time, your Moon sign will only be apparent to those who live with you, or people that are very close to you. In many ways, your Moon personality is the one you keep hidden. It is your inner core, which feels hate, jealousy, fear, and has fantasies that you often deny even to yourself.
On the other hand, it is your Moon personality that spontaneously feels and expresses joy and pleasure. It is the part of you that enjoys the little sensualities of life. The Moon in your horoscope modifies your Sun sign; it brings new forces, different motivations, and spiritual elements to the character of your Sun sign. For example, a Gemini-Sun person with Moon in Taurus will be more dependable than a Gemini-Sun with Moon in Aquarius. Here is another reason why we cannot define a person simply by their Sun sign.
The Moon is also a symbol of fertility and femininity; its sign colors one’s relationship with the mother, and with women in general. The Moon is constantly waxing and waning, from new Moon to full Moon and back. The house position of the Moon in your natal chart shows the area of life where you tend to be the most emotional, and where you often experience changing conditions. The house of the Moon also gives clues to the type of activity that occurs on the domestic scene.