In Vedic Astrology the Navamsa or 9th Harmonic chart is said to be a microscopic view of the 9th House and therefore the hidden undercurrent of our fate. The Navamsa serves many purposes. Out of all the Varga charts it is the one who is the constant companion of our main natal chart, the Rasi Chakra. It shows the underlying strength and weaknesses of planets in the Rasi. It is the reinforcement for better or worse of what is portended in our main horoscope. It heightens certain aspects of ourself and life. It is considered to be a marriage chart and shows the type of marriage interaction we might have and the description of the partner. It is said to give greater glimpse into the deities which are governing our spiritual progress and final emancipation; and greater glimpse into the mind of the soul.
The sign and ruler of the Navamsa Ascendant emphasizes that part of our character which will play an important role in our lives. For instance a person with a Scorpio Ascendant in the Rasi Chakra is usually seen as one who is secretive, interested in occult, powerful at emotional expression, interested in sexuality and different forms of energy, perceptive and a good psychologist. If Saggitarius rises in the navamsa then that person's second house in the Rasi Chart (Saggitarius falls in 2nd house) becomes a very important part of that person's Scorpionic nature. The person channels alot of their Scorpio nature in a resourceful manner through their speech, visionary insight and in a very philosophical, friendly way (2nd house and Saggitarian themes). If Jupiter, the lord of the Navamsa Ascendant is placed in the 7th amsa in Gemini, the person's philosophical tendencies via their Scorpionic character is amplified during one to one contact or in partnership stituations. The position of Jupiter in the Rasi Chart is particularly important because the Navamsa is highlighting it's role and if Jupiter were in Leo in the 10th House in the Rasi, that person has to express their philosophical communicative nature in one to one situations in their career or public domain and be recognised for it. This becomes one of the main recognizable traits of that person and their general life pattern and gives us an important glimpse into the soul's purpose.
Taking another example here is the chart of famous author Carlos Castaneda, born 25th Dec.1925,2:25pm, Cajamarca, Peru
Aries rises in the chart which is indicative of a simple and forthright personality, adventurous and pioneering, reckless and seeking challenges. Leo rises in the Navamsa Chart showing that his 5th house in the Rasi (Leo falls in the 5th house) becomes a very important part of his Aries nature, so he gets to channel his Arian themes mainly through his creativity, as a student, as a teacher, as an entertainer,through a spiritual path, in a highly original manner which also thrusts him into the spotlight (5th house and Leo themes). Sun, the lord of the Navamsa Ascendant is placed in the 12th amsa in Cancer so the person's teaching, learning, creative expression is happening in remote, foreign,secret and imaginative realms. The position of Sun in the Rasi Chart becomes important because the Navamsa is highlighting it's role and Sun is occupying the 9th house in Saggitarius in the Rasi, so Castaneda has to express his creative hidden and ambiguous qualities in relation to a teacher or guru (9th house) in which he also takes on the role of a spiritual guide or teacher as a result. This becomes one of the most important and recognizable themes of his life as a whole and gives us an important glimpse into his soul's purpose.
In the chart of guru Ramakrishna Paramahansa, born 18th February,1836,6.44 am, 87E44,22N53, India
Aquarius rises showing an eccentric, mystical, visionary, humanitarian personality with an unusual path. Saggitarius rises in the Navamsa showing that his 11th house in his Rasi (Saggitarius falls in the 11th House) becomes a very important part of his Aquarian nature, so his goal orientated focus and tendency to align himself to group participation for higher philosophical cause becomes highly emphasized (11th house and Saggitarian themes). Jupiter, the lord of the Navamsa Ascendant is placed in the 3rd amsa in Aquarius so this philosophical goal orientated team spirit is getting expressed in his communicative prowess and impartial leadership. The position of Jupiter in the Rasi Chart becomes important because the Navamsa is highlighting it's role and Jupiter is occupying the 5th house in Gemini in the Rasi, so his goal orientated and communicative efforts are used for teaching and guiding his students and is a major contributing factor for his birth.