The Vedic Astrology strongly emphasises that “Chandrama Nakshtranamadhipathi” means Moon is the significator or ruler of the stars. “Udu” means the planet Moon. That is why the Vimsotari Dasa system comprising 120 years is also called as Udu Maha Dasa. In this method 9 planets are allotted with their respective Number of years on the basis of a group of 3 stars assigned to them , in which moon is posited at the time of birth. As the mind is ruled by the planet moon Varaha mihira in his valuable “Brihat Jataka” chapter VIII stanza 11 reiterates
Prarabdha himaghou dhasha swagrihe maanaarthasoukyaavaha koujey dhooshayathi sthriyam budhagrahe vidhyasuhrdvikthadha
durgaranyapathaalayae krishikari simhe sitharkshennadha
kusthridha mrigakumbayorgurugrhe maanaarthasowkyavaha
The general meaning of the above sloka (not in the sense of verbatim) indicates that whatever be a Dasa or bhukthi of any planet that runs in a nativity , it is very important to note down the position of the Moon on the date of such commencement of dasa and bhukthi.
Hereinafter the position of such moon gives clue to interpret the entire dasa and bhukthi. This is a justified truth that any amount of reaping the good or bad result is suppose to affect directly the mind only, the ruler of which becomes the moon alone. This apart Varahamihira in his very first sloka itself pray the Sun God as Moorthithvey Parikalpathaha means Lord Shiva’s Ashtamoorthis viz., The Sun, Water,Earth, Air, Fire, Sky , Yayajuka (sacrifice performer) and the Moon are the primary agencies for the Creation , Protection and Destruction of the Universe. Mihira’s exemplory knowledge in having given greater importance to the Moon is also a reason that while all the planets are having debilitated Navamsa in their exalted sign, the planet moon alone is not having debilitated Navamsa in her exaltation sign Taurus.