time vedic

Smallest Unit of Time

Vedic astronomy give a very detailed division of the Time upto the lowest sub division level of prāņa (respiration), a time lapse of four seconds. The lowest sub divisions prāņa is the same part of the day as the minute is of the circle, so that a respiration of time is equivalent to a minute of apparent revolution of the heavenly bodies above the earth. The astronomical division of sidereal time are:

1 paramanu		60,750th of a second
1 truţi	=		29.6296 microseconds
1 tatpara	=		2.96296 milliseconds
1 nimesha	=		88.889 milliseconds
45 nimesha	=	1 prāņa	4 seconds
6 prāņa	=	1 vinādī	24 seconds
60 vinādīs	=	1 nadī	24 minutes
60 nādīs	=	1 ahorātra

As, according to modern standards, 24 hours make 1 day and night, one finds that, 1 nādi or daņda is equal to 24 minutes, 1 vinādī is equal to 24 seconds, 1 asu or prāņa is equal to 4 seconds, 1 nimesha is equal to 88.889 milliseconds, 1 tatpara is equal to 2.96296 milliseconds and finally 1 truţi is equal to 29.6296 microseconds or 33,750th part of second. It is really amazing that the Indian astronomers, at such a long time ago, could conceive and obviously could measure such a small interval of time like truţi. It should be mentioned here that, 1 unit of prāņa is the time an average healthy man needs to complete one respiration or to pronounce ten long syllables called guravakşara.

The Puranic division of the day is somewhat different. According to this, Kala (Time) is born out of Sun. The counting starts from nimesha (twinkling of an eye). (Source: Sūrya Siddhānta).

100 truti (atoms)	= 1 tatpara (speck)
30 tatpara (specks)	= 1 nimesha (twinkling)
18 nimesha (twinklings)	= 1 kashtha (bit)
30 kashtha (bits)	= 1 kala (~minute)
30 kala (minutes)	= 1 ghatika (~half-hour)
2 ghatika (half hour)	= 1 kshana/muhūrta (~hour)
30 kshana/muhūrta (hour)	= 1 ahorātra (~day).

Truti is referred to as a quarter of the time of falling of an eye lid.

1 muhūrta equal to 48 minutes, 1 ghaţi equal to 24 minutes. 1 kalā equal to 48 seconds, 1 kāşţhā equal to 1.6 seconds and 1 nimeşa equal to 88.889 milliseconds as obtained above. In its daily motion, the earth rotates around its axis at a speed of nearly 1660 Km per hour and its illuminated half is called ahh (day) and the dark half is called rātri (night). From the system of units of time given above, one finds that 60 ghaţis or nādīs make 1 day and night.

Vedic astronomical texts divide the above units of time broadly into two categories; (i) mūrttakālah and (ii) amūrtakālah. The units of the former kind are manifested (mūrttah) by the nature while, those of the latter kind are created by man. From this view point, ahorātra, prāņa or asu. nimeşa are mūrttakālah and the rest are amūrttakālah.

Hour

Deleting the leading letter ‘a’ and the trailing ‘tra’ from ‘ahorātra’, one is left with the word horā, and from this horā, another system of measuring time, the ‘Horā System’, introduced in this country by the celebrated Hindu astronomer Varāha Mihira, by dividing a day and night into 24 horās. Many believe that from this Horā System the entire world has adopted the present practice of dividing a day and night into 24 hours and moreover, from Sanskrit horā, English hour, Latin hora and Greek ora (ωρα) have been derived. It is interesting to note here that, one can derive the names of the seven days of a week from this Horā System as well. One has to assume a lord for each horā of the day and Ravivāra is to be accepted as the first day of the week, but counting is to be made in the reverse or descending order and the fourth place gives the name of the following day.

Seven Days of Week

Why seven days make a week? And wherefrom the names of these seven days have come? Every Indian will be pleased to know that it is also a gift of India to the entire world. We have seen earlier that, 60 ghaţis or daņdas make one day and night or ahorātra. Indian astronomers dedicated each ghaţi of the day to a planet as its lord and derived the name of the day as per the lord of the first ghaţi of the day.

surya	sunday
soma	monday
mangala	tuesday
budha	wednesday
guru	thursday
shukra	friday
shani	saturday
rahu & ketu	eclipse

The sun or Ravi being the most powerful among the planets, as well as the giver and sustainer of life, has been honoured to be the lord of first ghaţi of the first day of the week. Hence it is named Ravivāra or Sunday. In Figure-1, the lords of second and third ghaţis of Ravivāra are Mars and Jupiter respectively. Proceeding in this manner, Saturn is the lord of the 60th ghaţi of Ravivāra and the moon or Soma becomes the lord of the first ghaţi of the following day and hence it is named Somavāra or Monday (Moonday). One may notice here that in counting 60 ghaţis along the circle of Firure-1, one has to make 8 complete revolutions and 4 more planets and hence starting from a particular planet, the 5th place gives the name of the following day. In this manner one finally arrives at Śanivāra or Saturday (Saturnday) and starting from Śanivāra one observes that the next day is Ravivāra and thus the cycle is completed.

It may be recalled that the Horā System is not essential for naming he seven days of a week and primarily it was done by the Vedic astronomers dividing a day and night into 60 ghaţis or 60 daņdas. Hence, we may conclude without doubt that, it is the Vedic astronomers who named the seven days of a week using the original Indian system of dividing a day and night into 60 ghaţis and in their subsequent attempt they have shown that, one can arrive at the same results using 24 horās as well. In a verse (1/296) of Yājňavalkya Samhitā, the names of the planets are given exactly in the order of week days and hence there is every reason to believe that the names of the planets in that verse were mentioned particularly as the lords of the seven days of a week. This makes Professor S. B. Dixit to believe that the names of the seven days of a week were known in the times of Yājňavalkya Samhitā.

Fortnight, Month and Year

Units of time larger than day and week are fortnight and month. The Ŗgveda says, “aruņo māsak�-vikah’’ and Ācārya Yāska in his commentary over the verse says. “aruņo arocano māsak�-ņmāsānām cārddhamāsānām ca kartā bhavati” or the moon is the creator of months and fortnights. In Sanskrit the moon is called candramas and the word māsa has been derived from the parting syllable ‘mas’ of candramas. So it appears that, during the Vedic period people counted months and fortnights according to the phases of the moon. According to Professor S. B. Dixit, it was quite natural since one has to ascertain the duration of a solar month by tedious calculations, while lunar months arc visible to the naked eye and he writes, “Therefore it is clear that solar months came into being afterwards”.

Samvatsara �" The Year Cycles

Samvatsara is a Sanskrit term for "year". In Hindu tradition, there are 60 Samvatsaras, each of which has a name. Once all 60 samvatsaras are over, the cycle starts over again. The sixty Samvatsaras are divided into 3 groups of 20 Samvatsaras each. The first 20 from Prabhava to Vyaya are attributed to Brahma. The next 20 from Sarvajit to Parabhava to Vishnu & the last 20 to Shiva.

The 60 Samvatsaras are:

1. Prabhava	13. Pramāthin	25. Khara	37. Shobhana	49. Rākshasa
2. Vibhava	14. Vikrama	26. Nandana	38. Krodhin	50. Anala
3. Shukla	15. Vrisha	27. Vijaya	39. Vishvāvasu	51. Pingala
4. Pramoda	16. Chitrabhānu	28. Jaya	40. Parābhava	52. Kālayukti
5. Prajāpati	17. Svabhānu	29. Manmatha	41. Plavanga	53. Siddhārthin
6. Āngirasa	18. Tārana	30. Durmukha	42. Kīlaka	54. Raudra
7. Shrīmukha	19. Pārthiva	31. Hemalambin	43. Saumya	55. Durmati
8. Bhāva	20. Vyaya	32. Vilambin	44. Sādhārana	56. Dundubhi
9. Yuvan	21. Sarvajit	33. Vikārin	45. Virodhikrit	57. Rudhirodgārin
10. Dhātri	22. Sarvadhārin	34. Shārvari	46. Paritāpin	58. Raktāksha
11. Īshvara	23. Virodhin	35. Plava	47. Pramādin	59. Krodhana
12. Bahudhānya	24. Vikrita	36. Shubhakrit	48. Ānanda	60. Kshaya

Once the 60 names are finished, the next year starts with the first name again. This goes on in a cyclic manner.

Yuga

The units of time larger than a year are called yugas. The word yuga has been derived from yoga and yoga from samyoga, or conjunction of heavenly bodies. So one finds the origin of every unit of yuga to a specific conjunction of the heavenly bodies in the sky. In Indian astronomy, starting from a mere 5 year yuga to a vast Mahāyuga of 4,320,000 years are in vogue. Every 5 year, a conjunction of the sun and the moon occurs at the asterism Dhanişthā in the zodiacal sign Makara (Capricorn). The sun enters Makara, in the month of Māgha. Hence the conjunction recurs every 5 year on the new-moon day in the month of Māgha and that is the basis of counting a 5 year yuga. The Vedānga Jyotisa provides special names for these five years and they are Samvatsara, Parivatsara, Idāvatsara. Anuvatsara and Idvatvatsara [VS: 26/45, 30/16; TB: 1/4/10;111/4/1-4).

The planet V�-haspati (Jupiter) takes 1 year to cover a zodiacal sign and hence takes 12 years to complete its journey through all the 12 signs of the zodiac. This is the basis for counting a 12 year yuga and since it originates from the motion of V�-haspati, it is often called the Vrāhaspatya-yuga. It would be relevant to mention here that the Kumbha-Mela is held when V�-haspati enters the house of Kumbha (Aquarious) and hence the festival recurs every 12 years.

From the facts narrated above, one observes that a conjunction of the sun and the moon at Dhanişthā, while the V�-haspati (Jupiter) at makara (Capricorn), occurs every 60 years and that is the basis for counting a 60 year yuga. Hindu scriptures provide separate names for all the sixty years of a 60 year yuga.[4] The rare occasion when the sun, the moon and V�-haspati (Jupiter) meet at dhanişthā repeats at an interval of 865 million years. Such a conjunction occurs five times in a Kalpa.

Mahayuga (Chaturyuga) �" The Yuga Cycles

Beyond this level there are 4 epochs or yugas, namely, Krita Yuga, Treta Yuga, Dvapara Yuga, and Kali Yuga. All these four yugas together is called a chatur yuga, which means "four epochs"or also termed maha yuga that means "great epochs". Together a chatur yuga constitutes 4,320,000 human years and the lengths of each chatur yuga follow a ratio of (4:3:2:1:).

yuga	human years	ratio
krita-yuga	1,728,000 years	4
treta-yuga	1,296,000 years	3
dvapara-yuga	864,000 years	2
kali-yuga	432,000 years	1

1 chatur yuga (mahayuga)	4,320,000 human years

The ages see a gradual decline of dharma, wisdom, knowledge, intellectual capability, life span and emotional and physical strength.

Krita Yuga		Treta Yuga	Dvapara Yuga	Kali Yuga
other name	Golden Age or Satya Yuga (age of Truth)	Silver Age	Bronze Age	Iron Age
human years	1,728,000	1,296,000	864,000	432,000
climate	virtue reigns supreme	three quarters virtue and one quarter sin	one half virtue and one half sin	one quarter virtue and three quarters sin
human stature	21 cubits	14 cubits		3.5 cubits
human lifespan	lakh of years and death occurs only when willed.	lifespan is 10,000 years.	lifespan is 1,000 years.	lifespan is 100 or 120 years.