Astrology · Vedic

How Vedic astrology works

Jyotish — the sidereal zodiac, the Moon as the centre of the chart, and dashas as a timing system with no Western equivalent.

It measures against the fixed stars

Jyotish uses the sidereal zodiac, which begins from a fixed star rather than from the equinox. The equinox drifts about a degree every seventy-two years, so the two zodiacs have pulled roughly twenty-four degrees apart — around three-quarters of a sign. This is why your Vedic Sun is usually one sign back from your Western one, and why neither is the corrected version of the other.

This chart uses the Lahiri ayanamsha

The ayanamsha is the exact size of that gap, and it has to be chosen. This site uses Lahiri, also called Chitrapaksha, which the Indian government adopted as standard and which the large majority of Jyotish uses. Raman and Krishnamurti differ by about a degree — invisible most of the time, and occasionally decisive for a planet sitting close to a sign boundary.

The Moon leads, not the Sun

Ask an Indian astrologer for your sign and you will be told your janma rashi — the sign the Moon occupied at your birth. Western astrology leads with the Sun and reads purpose; Jyotish leads with the Moon and reads mind, temperament and emotional weather. Different question, so a different answer, and both can be right about the same person.

Nakshatras go finer than signs

Alongside the twelve rashis, the zodiac divides into twenty-seven nakshatras of 13°20′ each, and each of those into four padas. Two people with the Moon in the same sign can sit in different nakshatras and read as different people. The nakshatra your Moon occupied also sets your dasha sequence.

Dashas are the timing system

Rather than reading only what the sky is doing now, Jyotish divides a life into consecutive planetary periods. A mahadasha can run for nearly twenty years, so the same birth chart reads differently at thirty than at fifty — not because the chart changed, but because a different graha is running the chapter.

North and South Indian charts are the same chart

The diamond-shaped North Indian chart keeps the houses in fixed positions and moves the signs between them; the square-grid South Indian chart does the opposite. They are two drawing conventions for identical placements, like a tube map and a street map of one city — not two systems that disagree.

Vedic terms, defined

12 words this tradition uses, and what each one changes in a reading.

Sidereal zodiac

Signs measured against the fixed stars. What Vedic astrology uses — it lands roughly 24° behind the tropical one.

What it is: Two zodiacs, two starting points. The tropical zodiac begins at the spring equinox; the sidereal one begins against a fixed star. The equinox drifts by about one degree every seventy-two years, so the two have pulled roughly 24° apart — around three-quarters of a sign.
Why it matters: That gap is why your Vedic Sun is usually one sign back from your Western one. It is not a rounding error or a different opinion; it is two measuring systems answering honestly from different origins, the way two calendars can both give the correct date.
Common mistake: Believing one zodiac has been "debunking" the other, usually via the Ophiuchus story that resurfaces every few years. Astrologers have known about the drift for close to two thousand years — it is the reason the sidereal zodiac exists, not a discovery that undermines anything.

Ayanamsha

The exact gap between the tropical and sidereal zodiacs. Different schools use slightly different values.

What it is: The measured gap between the tropical zodiac and the sidereal one, currently around 24 degrees. Because the equinox drifts about a degree every seventy-two years the number is not fixed — it grows slowly, and a sidereal chart has to subtract the value for that particular date.
Why it matters: It is the single number that converts a Western chart into a Vedic one. Change it and every placement moves; change it enough and a planet crosses into the neighbouring sign. This chart uses Lahiri, the value adopted as standard in India and used by the large majority of Jyotish.
Common mistake: Assuming there is one correct value everyone agrees on. Lahiri, Raman and Krishnamurti differ by a degree or so, normally invisible but occasionally decisive for a planet near a sign boundary. Two competent astrologers can disagree about that planet and both be working correctly.

Lahiri ayanamsha

The standard value for the gap between the two zodiacs, adopted as official in India. It is what this chart’s Vedic side uses.

What it is: Also called Chitrapaksha, it fixes the sidereal zodiac so that the star Spica sits at zero degrees Libra. Named after N. C. Lahiri, it was adopted by the Indian government’s Calendar Reform Committee in the 1950s and is the value the large majority of Jyotish now uses.
Why it matters: It is the specific number this site subtracts to produce every Vedic placement. Choosing a different ayanamsha would shift every graha by around a degree — invisible most of the time, and decisive for a planet sitting close to a sign boundary.
Common mistake: Treating the choice as settled everywhere. The Raman and Krishnamurti ayanamshas remain in real use and differ from Lahiri by roughly a degree, so a chart calculated elsewhere may legitimately disagree with this one about a placement.

Rashi

A sidereal sign. Your janma rashi is your Moon sign — in Vedic astrology it matters more than your Sun.

What it is: Rashi is simply the Sanskrit word for a zodiac sign, measured sidereally. The one that carries your identity in Jyotish is the janma rashi — the sign the Moon occupied at your birth. Ask an Indian astrologer for your sign and this is the answer you get.
Why it matters: It is why the Vedic reading on this site can call you something other than the sign you have known your whole life, and be right both times. Western astrology leads with the Sun and reads purpose; Jyotish leads with the Moon and reads mind, temperament and emotional weather. Different question, different answer.
Common mistake: Deciding one of the two systems must be wrong. They use different zodiacs and lead with different planets, so disagreement is the expected result, not a contradiction to resolve. Reading them as two accounts of the same person is the whole point.

Nakshatra

One of 27 lunar mansions. Finer than a sign — it splits the sky into 13°20′ slices the Moon moves through.

What it is: A division of the zodiac into twenty-seven segments of 13°20′ each, rather than twelve of 30°. They are called lunar mansions because each covers roughly one day of the Moon’s travel, and every one carries its own ruling planet, symbol and character.
Why it matters: It is a far finer instrument than the sign. Two people with the Moon in the same rashi can sit in different nakshatras and read as different people — and nakshatra is what Vedic astrology actually uses for marriage matching, for timing, and to set the dasha sequence.
Common mistake: Treating it as a Vedic footnote to the sign. In a great deal of traditional practice the order runs the other way: the nakshatra is the primary placement and the rashi is the broader frame it happens to sit inside.

Pada

A quarter of a nakshatra. Four padas per mansion, so 108 divisions in all.

What it is: Each nakshatra divides into four quarters called padas, giving one hundred and eight divisions of the zodiac in total — the same one hundred and eight that recurs throughout Indian tradition. Each pada is 3°20′ wide.
Why it matters: Padas are how Jyotish reaches a level of detail a sign cannot. They feed the divisional charts and are part of how a name is traditionally chosen for a newborn, and two people in the same nakshatra but different padas are read differently.
Common mistake: Reaching for this much precision on a birth time you are not sure of. A pada is 3°20′ wide, so the Moon crosses one in about six hours and the Ascendant in under ten minutes — an approximate birth time cannot support a pada-level reading.

Lagna

The Vedic ascendant — the sidereal sign rising at your birth.

What it is: The Vedic ascendant: the sidereal sign rising on the eastern horizon at your birth. It is the same astronomical event as the Western Ascendant, measured against the fixed stars instead of the equinox, so it normally lands one sign earlier.
Why it matters: The lagna is house one, and every house in the chart is counted from it. In Jyotish it is often weighted above the Moon, and well above the Sun, for questions about the body, the direction of a life and the shape of the chart as a whole.
Common mistake: Expecting it to match your Western rising sign. It usually will not, for exactly the same reason your Vedic Sun does not match your Western one — and neither of the two is the corrected version of the other.

North Indian chart

The diamond-shaped Vedic chart. The houses stay in fixed positions and the signs move between them.

What it is: A square with a diamond drawn inside it, giving twelve compartments. The first house is always the diamond at the top centre and the houses always occupy the same places; what changes from chart to chart is which sign number is written into each compartment.
Why it matters: It is the standard drawing across northern India, and because the houses are fixed the eye learns to find the seventh house in the same spot on every chart. This is purely how the chart is drawn — the placements are identical to any other style.
Common mistake: Thinking North and South Indian charts are different systems giving different readings. They are two ways of drawing the same chart, like a tube map and a street map of one city, and an astrologer who works in either can read the other after a moment’s adjustment.

South Indian chart

The square-grid Vedic chart. The signs stay in fixed positions and the houses move between them.

What it is: A four-by-four grid with the middle removed, giving twelve boxes. The signs are fixed — Aries is always the same box — and the ascendant is marked so that the houses can be counted from it. It is the opposite convention to the North Indian chart.
Why it matters: It is standard across southern India, and because the signs are fixed the eye learns where Scorpio always sits. Which of the two this site draws is a display preference and nothing more; both show the same grahas in the same rashis.
Common mistake: Trying to read one as though it were the other. In the North Indian chart the fixed compartments are houses; in the South Indian chart they are signs. Reading a South Indian chart with North Indian habits puts every planet in the wrong house.

Graha

A Vedic planet. Nine of them, including the Moon’s two nodes, Rahu and Ketu.

What it is: The Sanskrit word for the nine bodies Jyotish reads: the Sun, Moon, Mars, Mercury, Jupiter, Venus and Saturn, plus Rahu and Ketu, the two points where the Moon’s path crosses the Sun’s. Graha means “seizer” rather than “planet”, which is closer to how they are treated.
Why it matters: The list itself is where the two traditions part company. There is no Uranus, Neptune or Pluto in classical Jyotish, and there are two points Western astrology usually treats as minor. Rahu and Ketu in particular carry a weight that has no Western equivalent.
Common mistake: Assuming Rahu and Ketu are planets astronomy somehow missed. They are not objects at all — they are the two intersections of two orbits, which is precisely why they are where eclipses happen.

Dasha

A planetary period. Vedic astrology divides a life into stretches, each ruled by one planet.

What it is: A planetary period. Rather than reading only what the sky is doing now, Jyotish divides a whole life into consecutive stretches, each governed by one graha, in a fixed sequence set by the nakshatra your Moon occupied at birth.
Why it matters: This is Vedic astrology’s principal timing tool and it has no real Western counterpart. It means the same birth chart reads differently at thirty than at fifty — not because the chart changed, but because a different planet is running the period.
Common mistake: Expecting a dasha to behave like a transit. Transits arrive from outside and last days or weeks; a dasha is a chapter that can run for nearly two decades, and it colours everything else happening inside it.

Mahadasha

The major dasha — the long one, running anywhere from six to twenty years.

What it is: The major period in the sequence — the long one. In the Vimshottari system this site uses, the full cycle runs a hundred and twenty years, and individual mahadashas range from six years for the Sun to twenty for Venus.
Why it matters: The mahadasha is the chapter heading of a life. Which planet is running, and how well it sits in your particular chart, is one of the first things a Jyotish reading establishes, because it decides which parts of the chart are currently switched on.
Common mistake: Reading a difficult planet’s mahadasha as twenty bad years. What matters is how that planet is placed in your own chart — a well-placed Saturn period can be the most productive stretch of a life, and a badly placed benefic can be a hard one.

Other traditions

Western Chinese · Ba Zi All terms