There are 12 rashi and each rashi has 9 Navansh there total number of Navansh in a Zodiac becomes = 12 × 9 = 108.
The entire Zodiac is equally divided into 27 parts and thus there are 27 Nakshatra in a Zodiac and every Nakshatra has 4 charan so total number of charan in a Zodiac of 27 Nakshatra becomes = 27 × 4 = 108.
So there is wonderful similarity between a Navansh and a Nakshatra chran. This strength to a Navansh chart which is imaginary when compared with Nakshatra which is real. So Navansh position derives strength from Nakshatra.
On the basis of its applicability it is put to use in two ways (1) as an independent chart (2) as a supportive chart.
(1) As an independent chart it is used to judge everything about one's life partner.
(1.1) One can also calculate the Longitude of planets for the Navmansh position of Planets of one’s horoscope and from this you can also work out shodash varga for the concerned Navmansh. It will give some enlarged view of the events of one’s life partner such as D24 of this Navmansh indicates the academic attainments of one’s life partner, D10 of this Navmansh about the profession of one’s life partner and so on. The Navmansh of this Navmansh will indicate something about that person very especial. But mind it it is possible only when the details of that person whose horoscope is under consideration should be highly accurate otherwise this system will not work.
(2) As supportive chart it is used to judge the entire events of one's life in addition to the main chart. Some of them are as under:
(2.1) Vargottam: Any planet occupies same rashi and same Navansh becomes vargottam planet and supposed to give the result as if it were in its own sign provided it should not occupy its debilitation rashi.
(2.2) it is auspicious to have vargottam lagna.
(2.3) any conjunction, aspect or yoga occurring in main chart as well as in Navansh chart becomes powerful.
(2.4) If planets form conjunction in chalit chakra and are found to be in aspectual relationship in Navmansh chart than their conjunction in chalit chakra becomes powerful and result giving and if otherwise than it is not much powerful.
(2.5) If any planet in chalit chakra is found to move from one house to another Bhava and in Navmansh it occupies the same house as that occupied by it in chalit chakra than it gives the results of the bhava it occupies in chalit chakra more effectively. If it occupies otherwise in Navmansh than its chalit chakra Bhava position will not be so effective.
(2.6) When Jupiter transits the Navmansh position or 5th & 9th from the position of any bhava lord of main chart than the auspicious results of that bhava occurs within the transit of Jupiter befitting the age of person. In Indian astrology Navansh chart finds a special position. In classical Indian astrology it is the only chart which is highly regarded after rashi chart. This is considered as source of strength. Even a weak planet in rashi chart but placed strong in Navansh chart becomes powerful.