Nakshatra () is the term for a lunar mansion in Hindu astrology and Buddhist astrology. A nakshatra is one of the 27 (sometimes 28) sectors along the ecliptic. Their names are related to the prominent star or asterism in or near the respective sectors. Every nakshatra is divided into four padas ( "steps").
The starting point for the nakshatras according to the Vedas is "Krittika" (it has been argued that this is because the Pleiades may have marked the start of the year at the time the Vedas were compiled, presumably at the vernal equinox), but in more recent compilations, the start of the nakshatra list is the point on the ecliptic directly opposite the star Spica, called Chitrā in Sanskrit. This corresponds to Ashwinī, a part of the modern constellation of Aries. These compilations, therefore, may have been compiled during the centuries when the sun was passing through Aries at the time of the vernal equinox. This version may have been called Meshādi or the "start of Aries".
The first astronomical text that lists them is the Vedanga Jyotisha.
In classical Hindu scriptures like the Mahabharata (Shalya Parvan,section 35) and Harivamsa, the creation of the asterisms is attributed to Daksha. The nakshatras are personified as daughters of Daksha and as wives of Chandra, the god of the Moon. When Chandra neglected his other 26 wives in favour of Rohini, his father-in-law cursed him with leprosy and proclaimed that the Moon would wax and wane each month. The nakshatras are also described as the daughters of Kashyapa.
Nakshatra is one of the five elements of a Pañcāṅga. The other four elements are:
Tithi Nityayoga Karana Vāra
Etymology The sanskrit term naksatra denotes a special class of heavenly bodies associated with the moon. The term naksatra consists of the root náks-(meaning "to attain") combined with the suffix -tra (or -l-atra, meaning "place"), meaning "the place to which the moon attains".
History Historically, nakshatra referred to stars or star-groups associated with the Moon's path. In later jyotisha, the term also came to denote 27 equal divisions of the ecliptic. In this equal division system, each nakshatra spans 13° 20'.
The Atharva veda contains a list of 28 nakshatras. Other ancient Indian scriptures like the Taittiriya Samhita (4.4.10.1-3) and the Shatapatha Brahmana (10.5.4.5) record 27 nakshatras.
In the Atharvaveda
In the Atharvaveda (Shaunakiya recension, hymn 19.7) a list of 27 stars or asterisms is given, many of them corresponding to the later nakshatras:Original text via
from
collated with the edition of Sakamoto-Goto identifies it as a hymn used for the daily worship of the nakshatras. The text lists 28 nakshatras, beginning with the Krttikās and including intercalary asterism Abhijit.
This 27-day cycle has been taken to mean a particular group of stars. This has to do with the periodicity with which the Moon travels past the specific star fields called nakshatras. Hence, the stars are more like numbers on a clock, through which the hands of time (the moon) pass. This concept is described by J. Mercay (2012) in connection with Surya Siddhanta. Astronomical derivation of nakshatras The choice between 27 or 28 nakshatras comes down to how ancient calendars calculated the speed of the Moon. During the Bronze Age (around 2000 BCE), astronomers used a calendar of 360 days, where the sun moved 1 degree per day and the moon moved an average of 13 degrees per day. Dividing the 360-degree sky by the Moon's 13 degree daily path gives an orbital period of 27.69 days .The astronomers rounded it to 28 nakshatras. Later, when a 365 day solar calendar was adopted, the Moon's updated daily speed of 13.2 degrees resulted in a shorter orbit of 27.27 days. Astronomers then rounded this down to 27 nakshatras and dropped the star Abhijit.
Vedic Calendar The Vedic calendar was based on a 360-day solar year composed of twelve 30- day months. Its earliest mention is found in the Rigveda texts. It arose from a ritual need to identify the exact nights of the new moon (amāvāsyā) and full moon (puranmāsī) for sacred sacrifices, which were otherwise difficult to determine by naked eye observation.
The priests tracked the Moon's night-by-night movement against the fixed stars, establishing a system of 28 nakshatras(lunar stations) representing the 28 nights the moon was visible during a synodic month. Early astronomers derived the name of each month directly from the specific nakshatra in which the full moon shone during that month.
Vedic origin of tithi The tithi is a lunar day in the Hindu calendar. In the 360-day vedic calendar, the Moon travelled an average of 13 degrees per day, while the Sun travelled 1 degree per day. As a result, the Moon separated from the Sun by 12 degrees (13 minus 1) every 24 hours. This time that the moon takes to pull 12 degrees ahead of the Sun, is called a tithi.
List of Nakshatras
In Hindu astronomy, there was an older tradition of 28 nakshatras which were used as celestial markers. When these were mapped into equal divisions of the ecliptic, a division of 27 portions was adopted since that resulted in a clearer definition of each segment, subtending 13° 20′ rather than the 12° ′ that 28 segments would give. In the process, the nakshatra Abhijit was left out without a portion. However, the Abhijit nakshatra becomes important when deciding on the timing of an auspicious event. The Surya Siddhantha concisely specifies the coordinates of the 27 nakshatras.
It is noted above that with the older tradition of 28 nakshatras each equal segment would subtend 12.85 degrees or 12° 51′. But the 28 nakshatra were chosen at a time when the Vedic month was recognised as having exactly 30 days. In India and China the original 28 lunar mansions were not equal. Weixing Nui provides a list of the extent of the original 28 nakshatras expressed in Muhurtas (with one Muhurta = 48 minutes of arc). Hindu texts note there were 16 nakshatras of 30 Muhurtas, 6 of 45 Muhurtas, 5 of 15 Muhurtas and one of 6 Muhurtas.
The 28 mansions of the 360° lunar zodiac total 831 Muhurtas or 27.7 days. This is sometimes described as an inaccurate estimate of our modern sidereal period of 27.3 days, but using the ancient Indian calendar with Vedic months of 30 days and a daily movement of the Moon of 13 degrees, this early designation of a sidereal month of 831 Muhurtas or 27.7 days is very precise. Later some Indian savants dropped the nakshatra named Abhijit to reduce the number of divisions to 27, but the Chinese retained all of their original 28 lunar mansions. These were grouped into four equal quarters which would have been fundamentally disrupted if it had been decided to reduce the number of divisions to 27.
Irrespective of why early Indian astronomers followed a Vedic calendar of exactly 12 months of 30 days it was this calendar and not a modern calendar of 365 days that they used for the astronomical calculations for the number of days taken for the Moon to complete one sidereal cycle of 360°. This is why initially they named 28 nakshatras on their lunar zodiac.
Each of the 27 nakshatras, starting with Ashvini and ending with Revati, has its own symbol, an associated mythological deity, and a planetary ruler (navagraha).The following list of nakshatras gives the corresponding regions of sky, as per Basham (1954).
No. NameAssociated starsDescription Image 1Aśvinī"The Horsemen"β and γ ArietisAstrological leader: Ketu (South lunar node) Symbol: Horse's head Deity: Ashvins, the horse-headed twins who are physicians to the gods Indian zodiac: 0° – 13°20′ Aries Tropical zodiac: 26° Aries – 9°20′ Taurus 2Bharaṇī"The Bearer"35, 39, and 41 ArietisAstrological leader: Shukra (Venus) Symbol: Yoni, the female organ of reproduction Deity: Yama, god of death and Dharma Indian zodiac: 13° 20′ – 26°40′ Aries Tropical zodiac: 9° 20′ – 22° 40′ Taurus 3Kṛttikā"To Cut"PleiadesAstrological leader: Surya (Sun) Symbol: Knife or spear Deity: Agni, god of fire Indian zodiac: 26°40′ Aries – 10° Taurus Tropical zodiac: 22° 40′ Taurus – 6° Gemini 4Rohiṇi"Radiant Maiden"AldebaranAstrological leader: Chandra (Moon) Symbol: Cart or chariot, temple, banyan tree Deity: Prajapati, rigvedic form of Brahma - the Creator Indian zodiac: 10° – 23°20′ Taurus Tropical zodiac: 6° – 19°20′ Gemini 5Mṛgaśiras"The Deer's Head"λ, φ OrionisAstrological leader: Mangala (Mars) Symbol: Deer's head Deity: Soma, the moon god Indian zodiac: 23° 20′ Taurus – 6° 40′ Gemini Tropical zodiac: 19° 20′ Gemini – 2° 40′ Cancer 6Ārdrā"The Moist One"BetelgeuseAstrological leader: Rahu (North lunar node) Symbol: Teardrop, diamond, a human head Deity: Rudra, rigvedic fierce form of Shiva Indian zodiac: 6° 40′ – 20° Gemini Tropical zodiac: 2° 40′ – 16° Cancer 7Punarvasu"Return Of The Light"Castor and PolluxAstrological leader: Guru (Jupiter) Symbol : Bow and quiver Deity: Aditi, goddess representing the infinity and the mother of Adityas Indian zodiac: 20° Gemini – 3°20′ Cancer Tropical zodiac: 16° – 29°20′ Cancer 8Puṣya"The Nourisher"γ, δ and θ CancriAstrological leader: Shani (Saturn) Symbol: Cow's udder, lotus, arrow and circle Deity: Bṛhaspati, counsellor of the gods Indian zodiac: 3° 20′ – 16° 40′ Cancer Tropical zodiac: 29° 20′ Cancer – 12° 40′ Leo 9Āśleṣā"The Embrace"δ, ε, η, ρ, and σ HydraeAstrological leader: Budha (Mercury) Symbol: Serpent Deity: Nagas, divine race of half-human, half-serpent beings that reside in the Patala Indian zodiac: 16° 40′ – 30° Cancer Tropical zodiac: 12° 40′ – 26° Leo 10Maghā"The Mighty"RegulusAstrological leader: Ketu (South lunar node) Symbol: Royal Throne Deity: Pitrs, 'The Fathers', family ancestors Indian zodiac: 0° – 13° 20′ Leo Tropical zodiac: 26° Leo – 9° 20′ Virgo 11Pūrvaphalgunī"The Former Reddish One"δ and θ LeonisAstrological leader: Shukra (Venus) Symbol: Front legs of bed, hammock, fig tree Deity: Bhaga, god of marital bliss and prosperity. Indian zodiac: 13° 20′ – 26°40′ Leo Tropical zodiac: 9° 20′ – 22°40′ Virgo 12Uttaraphalgunī"The Latter Reddish One"DenebolaAstrological leader: Surya (Sun) Symbol: Four legs of bed, hammock Deity: Aryaman, god of patronage and favours. Indian zodiac: 26° 40′ Leo - 10° Virgo Tropical zodiac: 22° 40′ Virgo – 6° Libra 13Hasta"The Hand"α, β, γ, δ and ε CorviAstrological leader: Chandra (Moon) Symbol: Hand or fist Deity: Savitr, the sun god Indian zodiac: 10° – 23° 20′ Virgo Tropical zodiac: 6° – 19° 20′ Libra 14Citrā"The Bright One"SpicaAstrological leader: Mangala (Mars) Symbol: Bright jewel or pearl Deity: Tvastar/Vishwakarma, artisan god Indian zodiac: 23° 20′ Virgo – 6° 40′ Libra Tropical zodiac: 19° 20′ Libra – 2° 40′ Scorpio 15Svātī"The Independent One"ArcturusAstrological leader: Rahu (North lunar node) Symbol: Shoot of plant, coral Deity: Vayu, the wind god Indian zodiac: 6° 40′ – 20° Libra Tropical zodiac: 2° 40′ – 16° Scorpio 16Viśākhā"Branching Out" α, β, γ and ι LibraeAstrological leader: Guru (Jupiter) Symbol: Triumphal arch, potter's wheel Deity: Indra, king of the devas and god of thunder, storms, and lightning, and Agni, god of Fire - representing the duality of water and fire Indian zodiac: 20° Libra – 3° 20′ Scorpio Tropical zodiac: 16° – 29° 20′ Scorpio 17Anurādhā "Following Radha" β, δ and π ScorpiiAstrological leader: Shani (Saturn) Symbol: Triumphal archway, lotus, bamboo Deity: Mitra, one of Adityas of friendship and partnership Indian zodiac: 3° 20′ – 16° 40′ Scorpio Tropical zodiac: 29° 20′ Scorpio – 12° 40′ Sagittarius 18Jyeṣṭhā "The Eldest" α, σ, and τ ScorpiiAstrological leader: Budha (Mercury) Symbol: circular amulet, umbrella, earring Deity: Indra, king of the devas Indian zodiac: 16° 40′ – 30° Scorpio Tropical zodiac: 12° 40′ – 26° Sagittarius 19Mūla"The Root" ε, ζ, η, θ, ι, κ, λ, μ and ν ScorpiiAstrological leader: Ketu (South lunar node) Symbol: Bunch of roots tied together, elephant goad