Vedic Period 4

                        Astronomy During the Vedic Period-4

                                          Nakshatra नक्षत्र

Nakshatras, as generally understood by all, is a group of stars in the sky used for astrological purposes. Why were they formed or created?  and What is their purpose? and is what we should know. 

The Vedic people first looked at the Sun and Moon to calculate time. The Moon was the basis of the heavenly clock. Therefore it was necessary to know the location/position of the Sun,  Moon and equinocal points in the Sky. These people regularly performed rituals and yagasयज्ञ and to know the appropriate time to perform these rituals, they had to know the exact position/ Location of the celestial object.

Today it is easy to know the position with the help of a celestial coordinate system. In the absence of such a system, a fixed/stationary reference frame was required to ascertain the location/position of a celestial object. 

Nakshatras provided this reference frame, in the sky, to the observers. All our Vedic works, including epics of Mahabharat, and the timing of events are given with reference to Nakshatras. 

The names of months in our Hindu calendar are based on these Nakshatras, this is because the nakshatra in which the full Moon was observed that month was named on that Nakshatra. 

Rashi/ Zodiac signs were adopted into Hindu astronomy around 200 BCE-300CE

The nakshatras are images of earthly objects. Some nakshatras have derived their names from their resemblance to particular figures. There are a few nakshatras who have derived their names differently.

A verse from Taittriya Brahman, 2.7.18.3

प्रवाद्ग्वा अग्रे क्षत्राण्यातेपुः ।॥ तेषामिंद्र: ॥ क्षत्रण्यादत्त ॥ नवा इमानि क्षत्राण्यभ्‌रवान्नितिं ।॥ तन्नक्षत्राणां नक्तत्रत्वं ।।

 derives  the word नक्षत्र as , those which are not,क्षत्र (moveable) are  नक्षत्र. This is as defined in Nirukta, explanation. There is another verse which describes नक्षत्र as the abode of Gods.

Nakshatras, also as stars in general are mentioned in Atharva Samhita 

अप त्ये तावयो यथा नुक्षत्ना यत्यक्तुभिः ॥ सुराय विदवचक्षसे ॥

~The stars and the night escape like thieves on the approach of  the Sun"

 Rk Samhita and Atharva Samhita, mention the word नक्षत्र as stars in general. Post-Vedic works also describe it as stars in general, including those in the Moon's path.

अथो नक्षत्राणामेषामुपस्थे सोम आहितः ॥।

~"The Moon is placed among the stars"~

Another metaphoric, description of nakshatra is found in Taittriya Brahman 1.5.2 

 सलिलं वा इवमंतरासीत्‌ । यदतरन्‌ ॥ तत्तारकाणां तारकत्वं । यो वा इहं यजते । अमुं स लोकं नक्षत्र ॥ तन्क्षत्राणां नक्षत्रत्वं ।॥। देवगृहा वं नक्षत्राणि ॥ य एवं वेद ॥ गृह्येवभवति ।\ यानि वा इमानि पृथिष्याहिचत्र्णण ।॥ तानि नक्षत्राणि ।॥ तस्माददलीलनामं शिचित्रे \॥ नावस्येन्नयजेत ॥ यथा पापाहे कुरुते ॥ तादृगेव तत्‌ ॥ |

                                                                    

which says 

"There was water in the centre. The tarakas are said to possess the prosperity of tarakatva(protectiveness) because they floated and saved themselves. He who performs oblation here goes (naksate/नक्षते) to that world. Hence the nakshatra significantly so-called, are the houses of Gods. He who knows this becomes the owner of a house. the nakshatras are the images of earthly objects. Hence a rite and an oblation should not be performed on an ugly nakshatra. It gives the same result as that performed on an inauspicious day"

This derivation traces the word to the root ' naksa'/नक्ष (to go). Virtuous people will go to heaven and become nakshatras. It puts out the idea that the nakshatras are the houses of Gods. (God here means planets, refer to my blog " Vedic Period -3")

Taittriya Samhita 7.5.25 mentions nakshatras as stars in general and in the Moon's path.

यो वा अश्वस्य मेध्यस्य शिरो वेद शीषण्वान्देध्यो भवत्युषा वा अश्वस्य

 मेध्यस्य क्ञिरः सूयंश्चक्षवातः प्राणव्चं रमाः भत्रं दिशः पादा अवां तरदिज्ञाः 

पशंवोऽहोरात्रे निमेषोधंमासाः पर्वाणि मासाः संधानान्युत्वोऽगानि

संवत्सर आत्मा रहमयः केशा न॑शत्राणि रूपं तारका अस्थानि नभो मासानि 

To summarise ~ "Dawn is the head of the horse. Heaven is his eye. The year is his soul. His form are the nakshatras and the stars are his bones”.

There are numerous definitions and derivations of Nakshatra evolved in the later periods. Something like 

 "नचरति, नक्षरति, अथ नक्षत्रति"

~They neither move nor deviate; they do not get destroyed and their greatness never diminishes over time; hence they’re known as nakshatras.~

Names of all nakshatras and their ruling deities are mentioned in various texts. Some describe them, some describe the origin of their manes etc.

Taittriya Samhita 4.4.10 mentions the names of all 27 nakshatras and their deities.

 कृत्तिका नक्षत्रमग्नि्वताग्नर्च स्थ प्रजापतेर्धातुः सोमस्यचं त्वा रुचे त्वा द्युते स्वा भसेत्व्ा ज्योतिषे त्वा रोहिणी नक्षत्रं प्रजार्पतिदेवता मुगशीषं नक्षत्रेसोमो देवता्रानतरडो  देवता । पुनवेसुमक्षत्रम दितिर्देवता तिर्य नक्षत्र बहस्पतिदेवताधेष नकषत्रेसर्पा देवता मघाग्नक्षत्रं पतसे देवता फल्गनीनक्षत्रसयंमा देवता फलग॒नी भैश्रं भगो देवता हस्तो(शक्षतरेसविता देवताचित्रा  नक्षत्रमिंदरो देवता स्वाती चकषत्रं वारं वता विशाखं क्षत्रमिदराण्नी देवतान्‌ राधां नक्षत्र मितो ॥ एकक 1 { | व देवता रोहिणी ्षत्रसिं द्रो देवता {विचृत्ती न्त्रं पितरो देवताषाढानषत्रमापो देवताषा्ा 1 दड्नकषर्ज विश्वेदेवा देवता श्रोणर नक्षत्रं विष्णुर्देवता शविष्ठा नक्षत्रं वसवो देवता शतभिषङनक्षनमिंदरो देवता श्रोष्ठपर्वा नक्षत्रमजएकपाहेवता प्रोष्ठपद न॑क्षत्र्माहर्बुध्नियो देवता रेवती त्त पुषा  | दे वताअश्विनी नश्षत्रसरिवनौ देवतापभरणीनं क्षत्रं यमो देवता पूर्णापश्चाद्यत्ते देवा अदधुः ॥

Atharva Samhita 19.7.1 mentions 

वचिन्राणि साकं दिवि रोचनानि सरीसृपाणि भुवने जवानि ¦ 

अष्टाविज्ञं सुमतिमिच्छमानो अहानि गीर्भिः सपर्यामि नाकम्‌ 

सुहवं मे कत्तिका रोहिणी चास्तु भद्र मृग्शिरः शमाद्रा।

पुनवेसु सूनृता चह पुष्यो भनुराश्लेषः अयनं मघा मे 

The first verse says" I being desirous of welfare, worship the heaven with the speeches, because 28 clusters of stars, like wonderful illuminating lights arranged in the form of nimble serpents, shine in the sky"

This shows that nakshatras are 28 in number. Taittriya Surti has mentioned Abhijit Nakshatra several times, however, the later texts mention only 27 Nakshatras. Why the 28th Nakshatra was dropped? No explanation is found. It appears that it was for ease of calculation?

Most of the verses, during the Vedic period, which describe the nakshatras start from the Nakshatra कृत्तिका(Pleiades). That means the list of nakshatras commenced with कृत्तिका as the first nakshatra during that period.

The Shatapatha Brahmana mentions that the कृत्तिका (Pleiades) "do not swerve from the east". This would have been the case with precision at 2950 BCE and was true also about 2000 BCE and was within 8-13 degrees around 8th to 6th BCE.

"Why should the list start with a specific nakshatra?" As previously mentioned in the Vedic Period blogs 1-3, the start of the year was based on either the Vernal Equinox (VE) or Winter Solstice (WS). To determine the exact position of VE or WS, the reference frame of Nakshatras was utilized since it's simple to identify the position of the equinoctial/solstitial colure using the reference frame of Nakshatras.

The Kritikadi system was in force during the Vedic period, meaning the Vernal equinox was in kritika nakshatra and the Winter solstice was in Sharavan/Dhanishta nakshatra. Hence the list started with  कृत्तिका Nakshatra.

 With the help of appropriate software, we can interpolate this conjunction backwards to know the exact date of this period. The diagram below explains this.

As of date, the list of nakshatras starts with अश्विनी and is known as अश्विनादि system. However,अश्विनी Nakshatra is not at the Vernal equinox.

Due to the precession of the equinoxes, we see the conjunction of रेवती/उत्तराभाद्रपद nakshatra with the vernal equinox as of date.

 It takes approximately 900 years for the nakshatra to shift from the equinoctal colure.

                            Origin of the names of a few nakshatras.

The names,पुनर्वसु (Castor and Pollux),चित्रा(Spica), मघा (Regulus)and रेवती(Zeta Piscium) did not indicate nakshatras but were already in use in a different sense. 

पुनर्वसु(a twin star)

अग्नीषोमा पुनवंसु अस्मे धारयतं रथिं ॥     ऋ. सं. १०,१६. १.

 ~is quoted as two Gods, who give shelter to those who offer prayers.~

 A dual form word for a dual star (quite remarkable as to how ancient observers identified correctly), they are seen in Gemini (मिथुन) zodiac sign. Did the sign Gemini get the twin status from this?

Chitra Magha(Regulus), the mighty, is used as chitramagha to denote " one having wonderful wealth. In almost all cultures/folklore this star is denoted as a king and mighty.

रेवती(Zeta Picium) means one possessing wealth and being prosperous.

These names were applied to Nakshatras, due to their munificence, and loveliness.  The people would have experienced, imagined or noticed these characteristics.

Aiteriya Brahaman mentions some legends regarding रोहिणी (Aldebaran),मृग(Lambda Orionis), and मृग व्याध (Sirus). The legends of Rohini, Mrigashirsha, Prajapati and antelope hunting all describe the cluster of stars around the Orion मृगशीर्षconstellation. All cultures have similar stories and legends regarding the Orion.

Taittriya brahman 1.5.2.2 gives out the vision of nakshatriya prajapati as, 

यो वं नक्षत्रियं प्रजापत्तिं वेद ॥ उभयोरनं लोकयोविदु : ॥ हस्त एवास्यं हस्तः ॥

 चित्रा क्षिरः ॥ निष्ट्चा ह्‌ दयं ॥ ऊरू विज्ञाखे ।। प्रतिष्ठान्‌ राधाः ॥ एष वै नक्षत्रियः प्रजापति : ॥

                                                                                                     

~"He who knows nakshatra Prajapati knows him as related to both worlds. Hasta is his hand, Chitra is his head, nistya(Swati) his heart, two Vishakha stars as his thighs, and Anuradha is the place to stand upon. This is nakshatriya Prajapati"~

This description fits the present-day observation, except for the star Swati, which is out of place. This is probably because the Proper motion of this star is faster and hence may have moved out.

Proper motion is the astrometric measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the centre of mass of the Solar System, compared to the abstract background of the more distant stars.

Origin of the names of अनुराधा (beta Scorpionis) and ज्येष्ठा(Antares, alpha Scorpionis) have been described in Taittriys Brahaman 1.5.2. 

Sayana, in his commentary on this verse, says ' It was a statement by the Gods with reference with the battle with the Demons... "We killed the eldest of them on ज्येष्ठा nakshatra." (Antares is the biggest star in the group, hence the name ज्येष्ठा)

The grammatical number in which the nakshatra names are used helps indicate the number of stars in each group. Mrigashirsha मृगशीर्षः(stars around Orion)and हस्त (group of stars appears as a palm of a hand, hence the name ) are a group of stars, but they are used in singular numbers. 

The singular number nakshatras are 

रोहिणी(Aldebaran),आर्द्रा (Betelgeuse), पुष्य (γ, δ and θ Cancri), चित्रा(Spica),स्वाति(Arcturus),ज्येष्ठा(Antares) ,मूल( ε, ζ, η, θ, ι, κ, λ, μ and ν Scorpionis),श्रावण(α,β and γ Aquilae), शततरका(γAquarii), रेवती(Zeta Picium). Indicating that each of them is a single star.

Nakshatras with dual stars are

पुनर्वसु(Castor and Pollux),पूर्वाफाल्गुनी(Delta and Theta Leonis),उत्तरा फाल्गुनी(Denebola),विशाखा(α, β, γ and ι Librae),अश्विनी (β and γ Arietis)

The balance of nakshatras are plural and have more than two stars.

                                            Saptarishi

The Vedas also refer to certain stars, other than those stars in 27 nakshatras,

अमी य ऋक्षा निहितास उच्चा नक्त" दद्र कुह चिहिवेय्‌: ॥

                                                                                 ऋ.सं. १ २४. १०

~" These Bears which appear to be placed at high elevation at night go somewhere in the day"~ 

( These constellations are popularly known as The Great Bear)

Shatpath Brahaman 2.1.2.4 observes 

सप्तर्षनु ह स्म वे पुरर्षा इत्याचक्षते ॥

~" The Saptarishis were called bears in ancient times"~

And Tandiya Brahman1.5.5 mentions as 

ऊध्वं सप्त ऋषीनुपतिष्ठस्व ॥।

~" Worship the seven sages above"~

Almost all the stars in the Nakshatras are, either the biggest, brighter, twin stars or as a group visible and easily identifiable.

A remarkable feat of Vedic people. It has been proved by various scholars that this Nakshatra system is a Hindu creation. Contrary to the popular belief that it was borrowed from the Chinese system. In fact, it is the other way around. 

____________________________

References

1. SB Dixit " Bhartiya Jyoti's Shastra" Part 1

2. William Brennand " Hindu Astronomy"

3. Ancient Indian Astronomy by RN Iyengar.

4. Ancient Astronomy by Prof TS Kuppanna Shastry

5. Research on Nakshatras by Dr Arjun Pai

6. Mythology of Nakshatras by Arvind Bhagwath