Those who have Gemini as their star sign are born when the sun was in Gemini, normally May 21 - June 20 (it differs slightly from year to year, because of the leap years). Therefore, it is also - more correctly - called the sun sign.
The sun in your horoscope is your natural self - what you are when you relax, when other planets in your horoscope are not active. It is your basic drive, a character you have as an ingredient - more or less evident in all you do and all you are. It is the most important point in your horoscope chart, but of course it is not the only thing that describes your personality. You need to look at all the components of your birth chart, to get a correct astrological description of yourself.
If your sun sign is Gemini, you are usually quite joyful and communicative. You like to talk, not worrying that much about what is being said. Generally, you don't take things that seriously, but are quick to joke and laugh. You are curious by nature, but impatient as well, so you prefer to learn a little about much, rather than much about a little.
A Zodiac sign does not give exactly the same influence all through its 30°. Its first third has something of a cardinal quality, whatever the quality of the sign as a whole is, its second third is slightly more fixed in quality, and the last third is more mutable.
If the sun is in the beginning of Gemini, you are very communicative, rarely quiet or discreet. You enjoy cheering folks up and getting their attention. If it's in the middle of Gemini you want to enjoy life, be with friends, make conversation and satisfy your curiosity. You are also prone to be well-versed. If the sun is at the end of Gemini, you are quite restless, jumping from this to that, initiating subjects for conversations and soon switching them. You have a hard time concentrating, but that doesn't worry you much.
Your father
The sun in the horoscope also represents your father (the mother is represented by the moon).
If you have the sun in Gemini, your relation to your father is a happy one, where both enjoy each other's company and speak freely to one another. You can joke, you can be at ease, but you don't really know each other that very well. Nor do you form very affectionate bonds. Still, you are quite content with things as they are. Even when you quarrel, it's no big matter.
The Planets
When another planet or other point of the horoscope is in Gemini, it is also affected by the sign, getting something of its character. Here are those points, what they stand for, and how they are affected by Gemini:
Sun
basic drive - Gemini brings joy and a light-hearted manner.
Moon
longing - Gemini brings a sense of humor, a good mood, and an unwillingness to take things seriously.
Mercury
curiosity - Gemini brings a quick intellect, and eloquence in speech and writing.
Venus
affection - Gemini brings playfulness and a delight in erotic adventures.
Mars
aggression - Gemini brings a sharp tongue, a mind set on intrigue, and a pen mightier than the sword.
Jupiter
luck - Gemini brings good fortune in small matters, and a sense that life is easy, that you get what you wish for.
Saturn
duty - Gemini brings some confusion as to what are lasting values, and a keen capacity to negotiate.
Uranus
contemplation - Gemini brings a mind that is quick to understand even complicated matters, but not that interested in developing them.
Neptune
fantasy - Gemini brings an entertaining fantasy, and dreams that jump from one thing to the next.
Pluto
catharsis - Gemini brings a lightness to great events in life, as if they are mere spectacles.
Ascendant
attitude - Gemini brings eloquence and a sense of humor appreciated by all, although regarded as superficial.
Self-Image - Gemini brings a relaxed view of oneself, without demands or frustrations, as if of little importance.
The Houses
In the astrological Houses, the Zodiac signs also bring their characters, influencing the environments described by the Houses. Here are the twelve Houses, what they stand for, and how Gemini affects them:
Identity - Gemini makes you seem joyous, easy to deal with, and superficial.
Resources - Gemini makes you want little, and get it easily.
Communication - Gemini makes you popular among friends, and quick to learn - but you forget as quickly.
Home - Gemini makes your family life happy and light-hearted, but not that caring.
Pastime - Gemini makes you always want to be entertained, and you get bored quickly.
Work - Gemini makes you quick to adapt to a new work, but indifferent to perfecting in it.
Partners - Gemini makes your relations come and go, equally fast, and they are rarely that serious.
Unknown - Gemini makes you curious about matters of metaphysics, and fate treats you mildly.
Travel - Gemini makes you constantly on the move, restless wherever you are.
Career - Gemini makes you quickly well-known, but not really taken seriously.
Ideals - Gemini makes you change your ideals often, never convinced that something is more true than something else.
Shortcomings - Gemini makes your life a bit heavy, with not enough laughter, and you have some difficulty getting in touch with others.
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