The Indian horoscope

An Indian chart — Jyotish — contains the same planets and the same twelve houses as a Western one, and is still calculated differently and read differently.

The four differences that matter

The zodiac. Sidereal rather than tropical, that is, set by the fixed stars rather than by the spring equinox. The difference now comes to about 24 degrees — a Western Aries is usually a Pisces in the Indian system. See sidereal and tropical.

The lunar mansions. 27 Nakshatras of 13°20' each, matching roughly the daily travel of the Moon. At least as important for interpretation as the signs — and in the West almost entirely out of use, although the tradition knew them.

The divisional charts. The Vargas: divisions of the zodiac into nine, twelve, sixteen parts and more, each of which yields a diagram of its own. The Navamsha, the ninefold division, is read for marriage and for how much weight a promise will bear. Western practice has nothing comparable.

The time lords. The Dashas divide a life into periods. The Vimshottari system shares 120 years among nine planets, with sub-periods and sub-sub-periods; the starting point is the position of the Moon in its Nakshatra at birth.

What is the same

More than most accounts admit. Both systems share the same Hellenistic root: the seven planets, the twelve houses, the doctrine of rulership, the aspects. The Western Firdaria and the Indian Dashas are close relatives and go back to the same Persian origin.

The two traditions are therefore not buildings alien to each other but two branches that parted just under two millennia ago.

What a reading needs

The same as in the West: date, exact time of birth, place. The birth time is if anything more delicate here, because the Vargas divide the zodiac finely — in the Navamsha a single section comes to a good three degrees, which is a few minutes of birth time.

A word of caution

In the West, Jyotish is often used by providers who calculate neither the sidereal zodiac nor the Dashas, but merely give Western readings an Indian vocabulary. Anyone looking for it in earnest asks about the Ayanamsa and about the Dasha system in use. Anyone with no answer to that is not calculating in the Indian way.