Mangala Dasha

The Mars Mahadasha is the period of Mangala in the Vimshottari dasha, lasting seven years. In the fixed sequence it follows the Moon and precedes Rahu. As the significator of energy, courage, conflict, and drive, Mars in its dasha is traditionally read as a time of action, competition, and assertion, when matters requiring force or initiative come to a head and disputes may sharpen, the results shaped by Mars's strength and placement in the birth chart. The dasha a person is born into is set by the nakshatra of the natal Moon. These are the interpretive conventions of the tradition; the Vimshottari system is a mathematical timing scheme keyed to the Moon's birth nakshatra, dividing the hundred-and-twenty-year cycle among the nine grahas in fixed shares.

No surviving classical text explains why the nine periods carry the particular lengths they do, seven years for Ketu, twenty for Venus, six for the Sun, ten for the Moon, seven for Mars, eighteen for Rahu, sixteen for Jupiter, nineteen for Saturn, and seventeen for Mercury; Brihat Parashara Hora Shastra gives the figures without deriving them, and modern scholars of Jyotisha have proposed various numerological and astronomical rationales without settling on one that is clearly original to the system. What is agreed is that the nine figures were fixed so as to sum to exactly one hundred and twenty, taken as a full symbolic human lifespan, and that this total, not any individual planet's period, is the number that gives Vimshottari, "one hundred and twenty," its name.

This period runs seven years of the 120 that the Vimshottari cycle divides among the nine grahas, and a life enters it at birth if the Moon stood in one of its lord's three nakshatras, Mrigashira, Chitra and Dhanishta.

The order of the nine periods is fixed and does not vary: Ketu, Venus, Sun, Moon, Mars, Rahu, Jupiter, Saturn, Mercury, and then Ketu again. It is the same order in which the nine grahas own the twenty-seven nakshatras, running three times through the list, which is what ties the dasha sequence to the Moon's position at birth. The nakshatra the Moon occupied gives the period a life begins in, and the fraction of that nakshatra already traversed gives how much of the period has already elapsed.

Each major period is subdivided in the same order and in the same proportions. A mahadasha is divided into nine antardashas, each running for the same fraction of it that its lord's own period bears to the whole 120 years, and the subdivision can be carried further into pratyantardashas and beyond. That is how the system produces timing fine enough to be tested: a combination in a chart is expected to show during the period and subperiod of the planets that form it.

Mars holds seven years, the same as Ketu, and the two are the shortest periods after the Sun's six. Because the nine lengths differ so widely, the point in the sequence at which a life begins has a large effect on how many complete periods it contains.