Jupiter rules the sign of Sagittarius
Expansion, religion, happiness
Planet of good luck, optimism, success, and generosity. Brings joy to life. Identified with idea of expansiveness and abundance. Jupiter's kingdom is luck, health and happiness, wealth and worldly goods, power and high position. Rules over knowledge, higher learning, breadth of vision, and honesty. Influence bestows a willingness to partake of life, to gather new experiences. Influence can make you extravagant, lazy, luxury-loving and blindly optimistic. Planet of blessings.

Jupiter from Voyager
Jupiter is the feeler for opportunity that you have out in the world. It passes along chances of a lifetime for consideration according to the basic nature of your Sun and Moon. Jupiter's sign position indicates the places where you will look for opportunity, the uses to which you wish to put on it, and the capacity you have to react and profit by it. Jupiter is ordinarily, and erroneously, called the planet of luck. It is "luck" insofar as it is the index of opportunity, but your luck depends less on what comes to you than what you do with what comes to you.
In the same sign as the Sun or Moon, Jupiter gives a direct, and generally effective, response to opportunity and is likely to show forth at its "luckiest".
If Jupiter is in the same sign as Mercury, sense impressions are interpreted opportunistically.
If Jupiter is in the same sign as Venus, you interpret emotions in such a way as to turn them to your advantage; your feelings work harmoniously with the chances for progress that the world has to offer.
If Jupiter is in the same sign as Mars, you follow opportunity with energy, dash, enthusiasm, and courage, take long chances, and play your cards wide open.
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Last here: 8 January 2010
Page born 12 Sep 2000
Reference from:
The Only Astrology Book You'll Ever Need
by Joanna Martine Woolfolk
Llewellyn's 2000 Sun Sign Book
Astronomy Picture of the Day Archive