Nakshatra
Nakshatra is the term for lunar mansion in Hindu astrology and Indian Astronomy. A nakshatra is one of 28 sectors along the ecliptic. Their names are related to a prominent star or asterisms in or near the respective sectors.
The starting point for the nakshatras according to Vedas is "Kritika", but, in more recent compilations, the start of the nakshatras list is the point on the ecliptic directly opposite to the star Spica called Chitrā in Sanskrit, which would be Ashvinī, an asterism that is part of the modern constellation Aries, and these compilations therefore may have been compiled during the centuries when the sun was passing through the area of the constellation 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, the creation of the nakshatras is attributed to Daksha. They are personified as daughters of Daksha and as wives of Chandra known as the Moon God, or alternatively the daughters of Kashyapa, the brother of Daksha.
In the Atharvaveda
In the Atharvaveda a list of 28 stars or asterisms is given, many of them corresponding to the later nakshatras:This 27-day time cycle has been taken to mean a particular group of stars. The relationship to the stars really has to do with the periodicity with which the Moon travels over time and through space past the field of the specific stars called nakshatras. Hence, the stars are more like numbers on a clock through which the hands of time pass. This concept is also described by Dr. Jessie Mercay in her research on Surya Siddhanta.
List of Nakshatras
In Hindu astronomy, there was an older tradition of 28 Nakshatras which were used as celestial markers in the heavens. When these were mapped into equal divisions of the ecliptic, a division of 27 portions was adopted since that resulted in a cleaner definition of each portion subtending 13° 20′. In the process, the Nakshatra Abhijit was left out without a portion. The Surya Siddhantha concisely specifies the coordinates of the twenty seven 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. 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 the reason why ancient 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.
The following list of nakshatras gives the corresponding regions of sky, per Basham.
| No. | Name | Associated stars | Description | Image |
| 1 | Ashwini | β and γ Arietis | ||
| 2 | Bharani "the bearer" | 35, 39, and 41 Arietis | ||
| 3 | Krittika an old name of the Pleiades; personified as the nurses of Kārttikeya, a son of Shiva. | Pleiades | ||
| 4 | Rohini"the red one", a name of Aldebaran. Also known as brāhmī | Aldebaran |
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| 5 | Mrigashīra "the deer's head". Also known as āgrahāyaṇī | λ, φ Orionis | ||
| 6 | Ardra "the moist one" | Betelgeuse | ||
| 7 | Punarvasu "the two restorers of goods", also known as yamakau "the two chariots" | Castor and Pollux | ||
| 8 | Pushya/Tishya "the nourisher", also known as sidhya or tiṣya | γ, δ and θ Cancri | ||
| 9 | Ashleshā "the embrace" | δ, ε, η, ρ, and σ Hydrae | ||
| 10 | Maghā "the bountiful" | Regulus | ||
| 11 | Pūrva Phalgunī"first reddish one" | δ and θ Leonis |
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| 12 | Uttara Phalgunī "second reddish one" | Denebola | ||
| 13 | Hasta "the hand" | α, β, γ, δ and ε Corvi | ||
| 14 | Chitra "the bright one", a name of Spica | Spica | ||
| 15 | Swāti "Su-Ati Very good" name of Arcturus | Arcturus | ||
| 16 | Visakha "forked, having branches"; also known as rādhā "the gift" | α, β, γ and ι Librae | ||
| 17 | Anuradha "following rādhā" | β, δ and π Scorpionis | ||
| 18 | Jyeshtha "the eldest, most excellent" | α, σ, and τ Scorpionis | ||
| 19 | Mula "the root" | ε, ζ, η, θ, ι, κ, λ, μ and ν Scorpionis | ||
| 20 | Purva Ashadha "first of the aṣāḍhā", aṣāḍhā "the invincible one" being the name of a constellation | δ and ε Sagittarii | ||
| 21 | Uttara Ashadha "second of the aṣāḍhā" | ζ and σ Sagittarii | ||
| 22 | Abhijit | ζ and σ Lyra | ||
| 23 | Shravana | α, β and γ Aquilae | ||
| 24 | Dhanishta "most famous", also Shravishthā "swiftest" | α to δ Delphini | ||
| 25 | Shatabhisha "Comprising a hundred physicians" | Sadachbia | ||
| 26 | Purva Bhadrapada "the first of the blessed feet" | α and β Pegasi | ||
| 27 | Uttara Bhadrapada "the second of the blessed feet" | γ Pegasi and α Andromedae | ||
| 28 | Revati "prosperous" | ζ Piscium |
Padas (quarters)
Each of the 27 Nakshatras cover 13° 20’ of the ecliptic each. Each Nakshatra is also divided into quarters or padas of 3° 20’, and the below table lists the appropriate starting sound to name the child. The 27 nakshatras, each with 4 padas, give 108, which is the number of beads in a japa mala, representing all the elements of Vishnu:| # | Name | Pada 1 | Pada 2 | Pada 3 | Pada 4 | Vimsottari Lord | Ruling Deity |
| 1 | Aśvini | चु Chu | चे Che | चो Cho | ला La | Ketu | Aswini Kumara |
| 2 | Bharaṇī | ली Li | लू Lu | ले Le | लो Lo | Venus | Yama |
| 3 | Kṛttikā | अ A | ई I | उ U | ए E | Sun | Agni |
| 4 | Rohiṇī | ओ O | वा Va/Ba | वी Vi/Bi | वु Vu/Bu | Moon | Brahma |
| 5 | Mṛgaśīrṣā | वे Ve/Be | वो Vo/Bo | का Ka | की Ke | Mars | Moon |
| 6 | Ārdrā | कु Ku | घ Gha | ङ Ng/Na | छ Chha | Rahu | Shiva |
| 7 | Punarvasu | के Ke | को Ko | हा Ha | ही Hi | Jupiter | Aditi |
| 8 | Puṣya | हु Hu | हे He | हो Ho | ड Da | Saturn | Jupiter |
| 9 | Āśleṣā | डी Di | डू Du | डे De | डो Do | Mercury | Rahu |
| 10 | Maghā | मा Ma | मी Mi | मू Mu | मे Me | Ketu | Pitr |
| 11 | Pūrva or Pūrva Phālgunī | नो Mo | टा Ta | टी Ti | टू Tu | Venus | Bhaga |
| 12 | Uttara or Uttara Phālgunī | टे Te | टो To | पा Pa | पी Pi | Sun | Sun |
| 13 | Hasta | पू Pu | ष Sha | ण Na | ठ Tha | Moon | Savitr |
| 14 | Chitrā | पे Pe | पो Po | रा Ra | री Ri | Mars | Vishwakarma |
| 15 | Svāti | रू Ru | रे Re | रो Ro | ता Ta | Rahu | Vaayu |
| 16 | Viśākhā | ती Ti | तू Tu | ते Te | तो To | Jupiter | Indra Agni |
| 17 | Anurādhā | ना Na | नी Ni | नू Nu | ने Ne | Saturn | Mitra |
| 18 | Jyeṣṭhā | नो No | या Ya | यी Yi | यू Yu | Mercury | Indra |
| 19 | Mūla | ये Ye | यो Yo | भा Bha | भी Bhi | Ketu | Varuna, Nirriti |
| 20 | Pūrva Aṣāḍhā | भू Bhu | धा Dha | फा Bha/Pha | ढा Dha | Venus | Apah |
| 21 | Uttara Aṣāḍhā | भे Bhe | भो Bho | जा Ja | जी Ji | Sun | Brahma |
| 22 | Śrāvaṇa | खी Ju/Khi | खू Je/Khu | खे Jo/Khe | खो Gha/Kho | Moon | Vishnu |
| 23 | Śrāviṣṭhā or Dhaniṣṭhā | गा Ga | गी Gi | गु Gu | गे Ge | Mars | Vasu |
| 24 | Śatabhiṣā or Śatataraka | गो Go | सा Sa | सी Si | सू Su | Rahu | Varuna |
| 25 | Pūrva Bhādrapadā | से Se | सो So | दा Da | दी Di | Jupiter | Aja Ek Pada |
| 26 | Uttara Bhādrapadā | दू Du | थ Tha | झ Jha | ञ Da/Tra | Saturn | Ahirbudhanya |
| 27 | Revati | दे De | दो Do | च Cha | ची Chi | Mercury | Pooshan |