The Study of Jyotisha · Chapter 4 of 54 · Part One · Beginnings

#The nakshatras

#Older than the signs

Long before Indian astronomers divided the zodiac into twelve signs, they divided it by the Moon. The Moon takes a little over 27 days to go round the sky. So the Vedic astronomers marked out 27 (sometimes 28) stations along its path, one for each night, and named each after a star or group of stars near it. These stations are the nakshatras, often called "lunar mansions" in English because the Moon "lodges" in one of them each night.

The nakshatras appear in the oldest Indian texts. The Vedic hymns and the ritual books called Brahmanas list them with their ruling deities, and the Vedanga Jyotisha (Chapter 47) uses them to keep the calendar. The twelve signs came into Indian astrology later. When they did, the two systems were fitted together, and they have stayed together ever since.

Even today, ask an Indian family about a child's birth and the first thing they will often tell you is the child's birth star (janma nakshatra) — the nakshatra the Moon was in at birth. It is used to choose the child's name (each nakshatra quarter has its own syllable), to match horoscopes for marriage, to time the planetary periods of a life, and to choose auspicious days. So learn the nakshatras well. You will use them more often than almost anything else in this course.

#How big is a nakshatra?

The zodiac has 360°. Divided into 27 equal parts, each nakshatra is

360° ÷ 27 = 13⅓° = 13°20′.

Each nakshatra is divided into four quarters, called padas ("feet") or charanas:

13°20′ ÷ 4 = 3°20′ per pada.

The whole zodiac therefore has 27 × 4 = 108 padas. (This is one of the reasons the number 108 is sacred in India.)

Now fit the nakshatras to the signs. A sign is 30°, and 30° ÷ 3°20′ = 9. So each sign holds exactly nine padas — two whole nakshatras and one quarter of a third, or some other combination adding to nine quarters. Varahamihira states this at the very start of his book: the zodiac begins at the first point of Aries, which is also the first point of Ashvini, and each sign consists of nine stellar quarters (Brihat Jataka I.4).

Four signs make 120°, and 120° is exactly 9 nakshatras (9 × 13°20′ = 120°). So the pattern of nakshatras inside the signs repeats every four signs:

• Aries, Leo and Sagittarius each begin with the first pada of a nakshatra (Ashvini, Magha and Mula).
• Cancer, Scorpio and Pisces each end with the last pada of a nakshatra (Ashlesha, Jyeshtha and Revati).

These six points — where a sign and a nakshatra begin or end together — are special, as you will see at the end of this chapter.

#The table of the 27

Learn this table slowly over several weeks. The columns are:

• No. and Name: the nakshatra's number and Sanskrit name.
• Span: from where to where, in degrees of the sidereal zodiac.
• Lord: the graha that rules it in the Vimshottari system of planetary periods (from the Brihat Parashara Hora Shastra, chapter on the Vimshottari dasha). These nine lords repeat three times in the same order: Ketu, Venus, Sun, Moon, Mars, Rahu, Jupiter, Saturn, Mercury.
• Deity: the god who presides over it, as Varahamihira lists them (Brihat Samhita 98.4–5, following the Vedic lists).
• Principal star: the bright star or group that marks it in the sky, with its usual modern identification (from Chidambaram Aiyar's note to Brihat Jataka I.4, and the Surya Siddhanta's chapter on the asterisms).

A few notes on the table:

• "Purva" and "Uttara" mean "former" and "latter". Three nakshatras come in pairs that were once thought of as a single larger station: Phalguni, Ashadha and Bhadrapada.
• Mula's deity is Nirriti, the goddess of dissolution. (The scanned English edition of the Brihat Samhita used for this course is damaged at this point in its table; Nirriti is the reading of the Vedic lists and of the standard Sanskrit editions.)
• Principal stars are approximate guides. The nakshatras are now defined as exact 13°20′ arcs, and their marking stars do not all sit neatly inside their arcs. Chitra is the exception that matters: the Lahiri ayanamsa is defined by placing Spica at exactly 180°, the boundary between Virgo and Libra, which is the middle of the nakshatra Chitra (Chapter 2).

#Remembering the lords

The nine lords in order — Ketu, Venus, Sun, Moon, Mars, Rahu, Jupiter, Saturn, Mercury — come round three times. A quick way to find the lord of any nakshatra: divide its number by 9 and look at the remainder.

Example. Anuradha is number 17. 17 ÷ 9 = 1 remainder 8. Remainder 8 → Saturn. So Saturn rules Anuradha. Check with the table: yes.

This order is the order of the planetary periods in the Vimshottari system, which is the main timing method of Indian astrology (Chapter 22). The nakshatra the Moon occupies at birth decides which planetary period a person is born into. So the lord column of this table is one of the most used facts in all of Jyotisha.

#Finding the nakshatra and pada of any position

Because every nakshatra is 13°20′, you can find the nakshatra of any longitude by division.

1. Write the longitude as a single number of degrees from 0° to 360° (Chapter 2).
2. Turn it into minutes of arc: multiply the degrees by 60 and add the minutes.
3. Divide by 800 (because 13°20′ = 800′). The whole number of the answer, plus one, is the nakshatra number.
4. Take what is left over (the remainder, in minutes) and divide by 200 (because 3°20′ = 200′). The whole number of that answer, plus one, is the pada.

Example 1. The Moon is at 15°20′ Leo.

1. 15°20′ Leo = 120° + 15°20′ = 135°20′.
2. 135 × 60 + 20 = 8,120′.
3. 8,120 ÷ 800 = 10, remainder 120. Nakshatra number 10 + 1 = 11, Purva Phalguni.
4. 120 ÷ 200 = 0, remainder 120. Pada 0 + 1 = 1st pada.

So the Moon is in the first pada of Purva Phalguni. Check with the table: Purva Phalguni runs from 13°20′ to 26°40′ Leo, and its first pada is 13°20′–16°40′ Leo. 15°20′ Leo is inside it.

Example 2. A planet is at 2°10′ Capricorn.

1. 2°10′ Capricorn = 270° + 2°10′ = 272°10′.
2. 272 × 60 + 10 = 16,330′.
3. 16,330 ÷ 800 = 20, remainder 330. Nakshatra 21, Uttara Ashadha.
4. 330 ÷ 200 = 1, remainder 130. Pada 2.

Uttara Ashadha runs from 26°40′ Sagittarius to 10°00′ Capricorn. Its first pada is in Sagittarius (26°40′–30°00′); its 2nd, 3rd and 4th padas are in Capricorn. So the 2nd pada begins at 0° Capricorn and ends at 3°20′ Capricorn. Our planet at 2°10′ is inside it. This example shows a nakshatra crossing a sign boundary — which, as the table shows, happens to many of them.

#Abhijit, the 28th

The older Vedic lists have 28 nakshatras, not 27. The extra one is Abhijit, "the victorious", named after the bright star Vega. Its deity is Brahma (Brihat Samhita 98.4–5). It sits between Uttara Ashadha and Shravana.

When the system was made regular, with 27 equal parts, Abhijit dropped out of the main count. It survives in two places:

• In muhurta (the choice of times, Chapter 39), Abhijit is given the span from 6°40′ to about 10°53′ Capricorn — the last quarter of Uttara Ashadha plus the first fifteenth of Shravana — and is counted as a very auspicious star.
• The name Abhijit muhurta is also given to the short period around local noon each day, which many traditions treat as auspicious for beginning things.

In ordinary horoscopy — planetary periods, birth stars, matching — only the 27 are used.

#The natures of the nakshatras

Muhurta, the art of choosing times, classifies the nakshatras by their nature. The classification is given by Varahamihira (Brihat Samhita, chapter 98) and repeated in every later book of muhurta. Each class is suited to a kind of action:

In horoscopy these classes are sometimes also read as hints about temperament, but their main home is muhurta, and Chapter 39 shows how they are used.

#Other groupings you will meet later

The nakshatras are grouped in several more ways, each used for a particular job. You do not need to learn them now; they are listed so that you recognise them when they appear.

• Gana ("group" or temperament): each nakshatra is deva (divine), manushya (human) or rakshasa (demonic in temperament). Used in marriage matching (Chapter 41).
• Yoni ("animal nature"): each nakshatra is paired with an animal — horse, elephant, sheep, serpent, dog, cat, rat, cow, buffalo, tiger, deer, monkey, mongoose and lion. Used in matching.
• Nadi ("channel"): each nakshatra belongs to one of three channels. Used in matching.
• Syllables: each pada has a sound used to begin a child's name. The Names page of this website uses them.
• Symbols: each nakshatra has a traditional image — a horse's head for Ashvini, a cart for Rohini, a hand for Hasta, a single bright jewel for Chitra, a drum for Dhanishtha, and so on. These images vary between later texts and are best treated as memory aids.

#The Moon in the nakshatras

The Moon moves about 13°10′ a day — very nearly one nakshatra a day. So the nakshatra changes roughly every 24 hours, though the moment of change can fall at any hour of the day or night, and a nakshatra can last anywhere from about 21 to 27 hours because the Moon's speed varies.

The nakshatra of the Moon at any moment is one of the five limbs of the panchanga, the Indian almanac (Chapter 5). The nakshatra of the Moon at birth is the janma nakshatra, the birth star. When people speak of "your star" in India, this is what they mean — not the Sun's sign as in Western astrology.

Example. On a given day the almanac says "Rohini until 14:32". That means the Moon is in Rohini (10°00′–23°20′ Taurus) until 2:32 in the afternoon, when it crosses 23°20′ Taurus and enters Mrigashira. A child born at 11:00 that morning has Rohini as the birth star; one born at 16:00 has Mrigashira.

#The knots: gandanta

Earlier we found six points where a sign and a nakshatra begin or end together. Three of them are the ends of the water signs:

• the end of Cancer, where Ashlesha ends and Magha (in Leo) begins;
• the end of Scorpio, where Jyeshtha ends and Mula (in Sagittarius) begins;
• the end of Pisces, where Revati ends and Ashvini (in Aries) begins.

At each of these points a water sign passes into a fire sign, and a nakshatra ruled by Mercury passes into one ruled by Ketu. Varahamihira names the last navamsa (the last pada) of Cancer, Scorpio and Pisces the riksha sandhis, "the joints of the stars" (Brihat Jataka I.7). Later texts call the zone on either side of these joints gandanta, "the end of a knot", and treat birth or beginnings there with caution. Varahamihira uses these joints in a few of his rules, for example in the chapter on conception and in the chapter on difficult combinations (Brihat Jataka IV.17, XXIII.4).

Notice what makes these points special: they are not arbitrary. They are where the two oldest divisions of the sky — the Moon's 27 and the Sun's 12 — meet exactly. Much of Jyotisha works like this: a rule that looks mysterious often turns out to rest on a simple fact of geometry.

#Summary

• The 27 nakshatras divide the zodiac into equal arcs of 13°20′, each with four padas of 3°20′, 108 padas in all. Each sign holds nine padas, and the zodiac begins with Ashvini at 0° Aries (Brihat Jataka I.4).
• Each nakshatra has a ruling planet (Ketu, Venus, Sun, Moon, Mars, Rahu, Jupiter, Saturn, Mercury, repeated three times), a presiding deity (Brihat Samhita 98.4–5) and a principal star.
• To find a nakshatra: longitude in minutes ÷ 800; to find the pada: remainder ÷ 200.
• Abhijit, the 28th, survives in muhurta.
• The nakshatras are grouped as fixed, movable, fierce, mixed, swift, soft and sharp for muhurta (Brihat Samhita 98), and by gana, yoni and nadi for matching.
• The Moon's nakshatra at birth is the birth star. The ends of Cancer, Scorpio and Pisces are the riksha sandhis or gandanta (Brihat Jataka I.7).

#Exercises

1. In which nakshatra and pada is a planet at 5°00′ Aries? At 20°00′ Gemini? At 29°00′ Pisces?
2. Find the lord of Uttara Bhadrapada (number 26) using the remainder method.
3. Which three nakshatras are ruled by Jupiter? In which signs do they lie?
4. A child is born with the Moon at 1°30′ Leo. What is the birth star? Is this close to a gandanta point?
5. Explain in your own words why there are exactly nine padas in every sign.

Answers: 1. 5°00′ Aries = 300′ → Ashvini (300 < 800), 300 ÷ 200 = 1 r 100 → pada 2. 20°00′ Gemini = 80° = 4,800′ → 4,800 ÷ 800 = 6 r 0 → Punarvasu, pada 1 (exactly at its start). 29°00′ Pisces = 359° = 21,540′ → 26 r 740 → Revati, pada 4. 2. 26 ÷ 9 = 2 r 8 → Saturn. 3. Punarvasu (Gemini–Cancer), Vishakha (Libra–Scorpio), Purva Bhadrapada (Aquarius–Pisces). 4. Magha, 1st pada; yes — it is just 1°30′ past the Cancer–Leo knot. 5. A sign is 30° and a pada is 3°20′; 30° ÷ 3°20′ = 9.