Shashtihayani Dasha (also spelled Shashtisama or Shashti-hayani, literally 'sixty-year') is a conditional udu (nakshatra-based) dasha of 60 years, applied in Parashari Jyotish chiefly when Surya occupies the lagna. The Brihat Parashara Hora Shastra lists it among the special dashas reserved for charts that meet a particular condition, in contrast to Vimshottari, which the same text calls the default for all births.

The applicability rule is the page's defining feature. Most commentators, following the BPHS conditional-dasha chapter as translated by R. Santhanam, hold that Shashtihayani is adopted when the Sun stands in the ascendant; some extend it to charts where the Sun is lord of the ascendant. Because the Sun tenants the rising sign in only a fraction of births, the system is uncommon by design — it belongs to the family of charts-specific dashas an astrologer reaches for when the qualifying placement is present, not to the everyday toolkit.

The sixty years are distributed across eight grahas; Ketu is excluded, as it is in several of the sama and conditional systems. The widely cited Santhanam structure assigns ten years each to Guru (Jupiter), Surya, and Mangal (Mars), and six years each to Chandra (Moon), Budha (Mercury), Shukra (Venus), Shani (Saturn), and Rahu. Three tens and five sixes sum to sixty (30 + 30 = 60), and the verified order runs Guru, Surya, Mangal, Chandra, Budha, Shukra, Shani, Rahu.

The allocation is genuinely disputed across sources, and a careful page names the disagreement rather than flattening it. The Santhanam reckoning above is the most commonly published. Other tabulations circulate a 54-year variant of the same system, and some popular write-ups assert that the Sun takes the dominant single share — a reading the verified per-graha breakdown does not support, since the Sun is one of three grahas tied at the largest ten-year period, not a lone holder of the lion's portion. Where a calculator or commentator departs from the 10/10/10/6/6/6/6/6 figures, the difference should be attributed to that source, not presented as the settled rule.

The starting point is fixed by the nakshatra of the natal Moon, as in other udu dashas. The twenty-seven nakshatras (with Abhijit counted) are mapped to the eight dasha lords in order, so the lord whose nakshatra group contains the Moon's longitude opens the sequence; the balance of that first mahadasha is prorated from how far the Moon has travelled through its nakshatra. Guru governs the opening group from Ashwini through Krittika, Surya the group from Rohini through Punarvasu, Mangal from Pushya through Magha, and so on through the remaining lords.

In practice the dasha is read like any Parashari period system: each mahadasha subdivides into antardashas (bhuktis) in the same lord-sequence and proportional to each lord's share of the cycle, and an astrologer judges a period by the dignity, house-rulership, and placement of the ruling graha rather than by the dasha label alone. Its place among the dashas is that of a specialist instrument — a second timing lens applied when a Sun-in-lagna chart invites it, layered against the universal Vimshottari reading rather than replacing it. Parashara's own guidance is that the conditional dashas are chosen by their eligibility marks, the most fitting one taken up for a given chart.

How It Is Read

Shashtihayani is significant because it is one of the few classical timing systems keyed to a single solar condition — the Sun rising in the ascendant — which makes it a targeted instrument rather than a universal calendar. For the charts that qualify, it offers a 60-year lens weighted toward the luminary and the masculine, fiery grahas: Guru, Surya, and Mangal each hold a full ten-year mahadasha, the longest in the scheme, so periods of authority, vitality, and assertion are given structural prominence over the cycle. This is distinctive against Vimshottari, where Shukra and Shani hold the longest periods and the Sun only six years. The system also illustrates a broader principle in Parashari dasha theory: that the rising graha can reorganise the whole rhythm of a life's unfolding. An astrologer who finds the Sun in the lagna gains a purpose-built second reading, weighed against the default, rather than a single fixed timeline.

Connections

Shashtihayani belongs to the conditional branch of Parashari udu dashas, alongside Ashtottari (108), Shodashottari (116), Dwadashottari (112), Panchottari (105), Shatabdika (100), Chaturashiti-sama (84), and Dwisaptati-sama (72) — each triggered by its own eligibility mark. Its closest sibling is Shattrimsha-sama (36), the other solar-keyed conditional dasha, which likewise excludes Ketu and turns on the Sun by day. The sharpest contrast is with Vimshottari, the universal 120-year dasha that needs no condition and weights Shukra and Shani most heavily, where Shashtihayani elevates Surya, Guru, and Mangal. It is structurally unlike the Jaimini Chara rashi dasha and the pada-based Kalachakra, both of which are not graha-period systems. All trace to the dasha chapters of the BPHS; see the dasha hub for the full set.

Further Reading

  • Brihat Parashara Hora Shastra, conditional-dasha chapters (R. Santhanam translation) — the source verses defining Shashtihayani's eligibility and period lengths.
  • Hart de Fouw and Robert Svoboda, Light on Life — chapter on the dasha systems and how conditional dashas are selected.
  • K. N. Rao, The Nakshatra (Star) System of Prediction — treatment of the udu dashas beyond Vimshottari.
  • B. V. Raman, Hindu Predictive Astrology — survey of the special and conditional dashas.
  • Sanjay Rath, dasha writings on the Parashari period systems and their applicability conditions.

Frequently Asked Questions

What is Shashtihayani dasha?

Shashtihayani Dasha (also Shashtisama) is a conditional nakshatra-based timing system of 60 years described in the Brihat Parashara Hora Shastra. It is applied chiefly when the Sun occupies the ascendant, and by some commentators when the Sun is lord of the ascendant. The sixty years are divided among eight grahas, with Ketu excluded, and it serves as a specialist alternative to the universal Vimshottari dasha for the charts that qualify.

How are the 60 years of Shashtihayani dasha divided among the planets?

In the commonly published Santhanam structure, Jupiter, the Sun, and Mars each receive a ten-year mahadasha, while the Moon, Mercury, Venus, Saturn, and Rahu each receive six years. Three tens and five sixes total exactly sixty years. The verified order is Jupiter, Sun, Mars, Moon, Mercury, Venus, Saturn, Rahu. Ketu has no period in this system, as in several other conditional dashas.

When is Shashtihayani dasha used?

It is a conditional dasha, adopted only when its eligibility mark is present — most sources require the Sun in the lagna, and some extend it to charts where the Sun rules the lagna. Parashara groups it with the other special dashas an astrologer chooses by their qualifying conditions, applying the most fitting one for a given chart alongside the default Vimshottari reading rather than in place of it.

How is the starting period of Shashtihayani dasha calculated?

As in other udu dashas, the opening period is set by the natal Moon's nakshatra. The twenty-seven nakshatras are mapped in groups to the eight dasha lords, so the lord whose group contains the Moon's longitude begins the cycle. The balance of that first mahadasha is prorated from how far the Moon has moved through its nakshatra, and the remaining lords follow in the fixed Jupiter-to-Rahu order.

Is the Shashtihayani allocation disputed?

Yes. The 10/10/10/6/6/6/6/6 figures from the Santhanam translation of the BPHS are the most widely cited, but a 54-year variant of the same system circulates in some tabulations, and certain popular write-ups claim the Sun takes a dominant single share. The verified per-graha breakdown does not support a lone large solar period — the Sun ties Jupiter and Mars at ten years. Departures from the standard figures should be attributed to their specific source.