Vedic Period-2

  Astronomy During the Vedic Period-2

Time Units

KALPA and YUGA are common terms and, are understood as some unit of time denoting a specific period. However, KALPA is not used as a unit of time in Vedas, though it is used extensively during the post-Vedic period.

YUGA as a unit of time, finds a mention in the Vedas in several places. These references in the Vedas suggest that the word yuga does denote a certain period of time. This period is not quantified but is a smaller period of  5 to 10 years.  For example as given in the following verses

 युगे ुगे विदध्यं मृणद्भ्योगनेरथि यशसं धेहि नव्यसीं ॥ 

                                                                   | ऋ. स. ६. द. ५.

"Oh! God of fire, give riches and success to us who offer new words of praise to thee for the  sake of sacrifices in each yuga"__ Rk Samhita

था ओषधीः पूर्वां जाता देवेभ्यस्त्रयुगं पुरा ।

                                      ऋ. सं, १०. 8७. १.

"The herbs created by Gods in three yugas before" ----Rk Samhita. The Scholars have interpreted " Triyuga" as three yugas Kreta, Treta and Dwapar or three seasons Vasant, Varsha and Sharad.

All these references show yuga is used to denote some period, after which the event repeats itself. A periodic nature of time after which a phenomenon recurs, like an eclipse, planet rotations etc.

The word Yuga is used for 

 Emotional, Symbolic, calculation and calendric. Do, not confuse with Dwapar, Treta, Kali...of 432000 years as the duration of Yuga. These are used for calculation purposes.

In Vedang Jyotish, the yuga is taken to be a cycle of 5 years. The names of these years are संवत्सरः,परिवत्सरः,इदावत्सर:' अनुवत्सरः,इद्वत्सरः. These names occur in the Vedic texts but they do not occur in the Vedang Jyotish. There are many verses which mention these years in the ancient Vedic texts. it appears to be a system similar to the 5-year cycle of Vedang Jyotish. 

                    The months were Lunar and the Year was Solar

The caption appears odd, how can we have two different systems to count the same duration. However, this appears logical as most of the astronomical database was compiled by observation during the Vedic age.

It was natural in the Vedic age that the month was counted from the Moon. "Puranmasi", which we understand as the full Moon literally means the tithi on which the month ends. MASA a synonym for Moon was adopted as a time unit for months.

Numerous verses describe the year, having  12 months (13th month as intercalary for adjustment),360 days. The description is, both direct and indirect,for example

्रीणिच वशतानि षष्टिर संव॑त्सरस्याहानि.--सप्त च वं रतानि विंशतिश्च संवत्सरस्थाहोरात्रयेः `                                                             ए. ब्राः ७. १७.

"A year has 360 days , a year has 720 days ans nights together"

 Taitareya Brahman 3.8.3 describes the year and intercalary month, metaphorically as under

दा दशारत्नी रहना कतेव्यए २ च्रथोदशारत्नी देरिति ॥ ऋषभो वा एष ऋतूनां ॥ यत्संवत्सरः ।। तस्य त्रयोदशो मासो विष्टपं ।

॥ ऋषभ एष यज्ञानां ।॥

। यदहवमेधः॥ यथावा ऋवभस्व विष्टपं !! एवमतस्य विष्टपं ॥            ते. त्रा. ३.८. ३.

"Should the reigns in a horse sacrifice be 12 cubits in length or 13? The year of (six) seasons is a kind of bullock whose hunch is the 13th month. The horse sacrifice is the best of all sacrifices..."

The seasons are formed due to the Sun, therefore it was logical to assume that a year has elapsed when a particular season returns, hence the year counting was solar. Full moon to full Moon would then constitute a masa or a month. So the year was solar and the month Lunar.

To keep the seasons and the corresponding month synchronised with the actual environment, some adjustment was done  to match the Lunar month and the Solar year. The indirect reference to intercalary month points to the fact, that some methods were adopted for synchronisation.

As the months were Lunar, the year counting would also have been Lunar, but the Lunar year did not have 360 days, but less than that. However in practice a savan/solar year was in use and hence a mention of intercalary month adjustment, as mentioned above.

 However, In the Hijri calendar the month, say, Muharram, will pass through all seasons because the adjustment is carried out after 33 years (instead of 30-32 months).

There is no reference to any rule, stating how the intercalary month be adjusted during the Vedic age. However, Vedang Jyotish does give out the rules of adjustment in the later period.

Apart from the solar year, we have references to the Savana and Lunar years. There is no reference to Sidereal and Jovian years in the Vedas.

Days

 A Lunar month has only 29 1/2 days, not 30 days as is understood. So in two months, the total number of days is 59. This discrepancy of 1 day needs adjustment. 

A verse from Taittriya Samhita 7.5.6 says

                              षउहर्मासात्संपाचाहरत्सु्चंति             | त. सं. ७.५. ६.

" A day is omitted after some sadahas and masa are observed"

The reason for omitting the day is mentioned in Taittriya Brahaman 5.10.2

                                   यथा वे टतिराध्मात एवसंवसरोनुत्सुष्टः

" If a day is not omitted then the year will swell like bellows made of leather"

Interestingly in the Vedic period, One day of 24 hrs is called 'aha' अह: and a group of six such days are called sadahas and five sadahas make one masa (month) and several such sadahas and masas constituted to make 360 days of savanna year.

So a 6-day week and a 5-week month were prevalent during the Vedic period.

There is no mention of a 7-day week and the names of the 7 days of the week, during the Vedic period, as we know it today.

The only mention is of the 15th day as panchadashi पञ्चदशी. Other terms such as pratipada dwitiya etc may have been used to denote (day one, day two etc), day and nights (what we understand as Tithi), words like Shukla Chaturdashi, and Krishna Panchami have been found to denote the day of light and the dark half of the month.

As per, Taittriya Brahaman different names have been given for the days and nights in the light and dark half of the month. There are 15 names for day and 15 names for night.

 अह: is used to mention a day in a neuter gender form, whereas the word रात्रि, is feminine, hence the names of the nights are used in feminine gender. So ahoratra अहोरात्र is day and night. Hora होरा doesn't come from अहोरात्र.

Tithi

 We all are familiar with the word Tithi तिथि, meaning a day in Lunar month. However, during the Vedic  period, there is no mention of the word तिथि,(the way we understand it today)

                                       Length of the Day

The variable length of the day is due to the Sun.

The following lines in Rk Samhita 8.48.7 describe the phenomena. 

सोमराजन्‌ प्रण आयू'षि तारीरहानीव सूर्यो वासराणि ॥

                                                          ऋ. सं, ८. ४८. ७.

"Oh! Somraja! Increase the length of our lives, just as the sun increases the length of the day, which are dwellings of the world"

The Equinoctal Day

There are a lot of references to the equinox in the Vedas, during this period. The mentions are in the form of annual sacrifices, and that period mentioned relates to the equinox as an indirect meaning. But there is no explicit definition of equinox, on which the days and nights are equal.

........to be continued with parts of the Day.

_________________________________________

References

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

2. William Brennand " Hindu Astronomy"

3. Coolebroke Essays.

4. Gen Alexander Cunningham "Book of Indian Eras"

5. Dr Nilesh Oak talks.