Contribution Of Hindu Scriptures To Archaeoastronomy

Astronomers were interested in information related to eclipses, supernovae and other phenomena in the ancient world. Such phenomena are described in Indian texts, but there has been a long-standing controversy about the chronology of these texts. Although traditional history places the bulk of the Vedic texts in the period of the fourth to the second millennium BC, the chronology proposed by Max Muller and generally adopted in the West dates Rigveda to 1200-1000 BC, the other Vedic texts to 1000-800 BC and the Brahmanas to 800-600 BC.

Influenced by this scheme, Vedanga Jyotisa, the Vedic manual of astronomy, which has an internal date of about 1370 BC, has been ignored by the historians of astronomy, and it has been arbitrarily assigned to a period one thousand years later. Vedic books do refer to several early astronomical events that take us to various times in the broad period of 4000-2000 BC. For example, there is the well-known statement in the Satapatha Brahmana that the Krttikas (Pleiades) do not swerve from the east, which was true of about 2000 BC.

Likewise, the earliest naksatra lists start with the Krttikas, and it is generally accepted that these lists count the naksatras with the rising on the vernal equinox, but the critics have discounted such evidence arguing that we cannot be certain that the naksatras were assigned the same part of the sky as in later Indian astronomy. In this article, we show that it is possible to, unambiguously, date the rites described in the Brahmanas, to the second millennium BC. This means that the Max Muller chronology must now be rejected. For the archaeoastronomer, this allows the placing in context of a vast amount of astronomical information.

The Brahmanas recognise that the speed of the sun varies with the seasons. The year-long rites of the Brahmanas were organised with the summer solstice (visuvant) as the middle point. There were two years: the ritual one started with the winter solstice (mahavrata day), and the civil one started with the spring equinox (visuva). Vedic rites had a correspondence with different stages of the year and, therefore, astronomy played a very significant role in that society. These rites counted the days up to the solstice and in the latter half of the year, and there is an asymmetry in the two counts. This is an astronomical parameter, which had hitherto escaped notice that allows us to date the rites to no later than the second millennium BC.

Several aspects of the astronomy described in the earliest texts of India have recently become known. Most of that material was based on the astronomy of the fire altars. The fire altars are made in a manner so that their areas correspond to the lengths of the lunar or the solar years. As there is a difference between the two types of year, an increase in the area of the fire alter that equals the difference is prescribed in its second construction. Finally, there is a prescription that 95 such altars be built in a sequence defining a 95-year cycle of intercalation. Recent research from a variety of fields have led to a new understanding of the chronology of Vedic literature.

Archaeologists and geologists have established that Sarasvati, the mightiest river of the Rigvedic era, which ran down to the sea during that period, is the same as the Ghaggar-Hakra. Since there existed flourishing settlements on the banks of the river prior to about 1900 BC, and the fact that we see small settlements on the dry bed which date to the middle of the second millennium BC, it is clear that the river dried up around 1900 BC, perhaps due to a major tectonic upheaval. As the Rigvedic hymns speak of Sarasvati flowing to the sea, the only conclusion open to us is that the Rigvedic era should be considered to be prior to c. 2000 BC.

The traditional dating of the Rigveda, considered to belong to an era prior to the Mahabharata war, is considerably earlier than this period. According to Aryabhatta, the Mahabharata war took place c. 3100 BC, and according to Varahamihira, it took place c. 2400 BC. It appears that the discrepancy between the two traditions arose due to conflating interpretations when a calendrical review occurred sometime before Aryabhatta . On the other hand, according to a French team that surveyed the dried Sarasvati bed, the river dried up much before 1900 BC, and during the Harappan era (2600-1900 BC), the region was irrigated by the means of canals. If this were true, then the era of the Rigveda would come even closer to one of the traditional dates. Nevertheless, to be as conservative as possible, we take c. 2000 BC as the closing of the Rigvedic age. The astronomy of this era has been described recently.

The two halves of the year

Aitreya Br. 4.18 describes how the sun reaches the highest point on the day called visuvant and how it stays still for a total of 21 days with the visuvant being the middle day of this period. In Pancavimsa Br. (Chapters 24 and 25), several year-long rites are described where the visuvant day is preceded and followed by three-day periods. This suggests that the sun was now taken to be more or less still in the heavens for a total period of seven days. So it was clearly understood that the shifting of the rising and the setting directions had an irregular motion.

SB 4.6.2 describes the rite called gavamayana, the “sun’s walk” or the “cows’ walk.” This is a rite which follows the motion of the sun, with its middle of the visuvant day.

Yajurveda (38.20) says that the ahavanıya or the sky altar is four-cornered since the sun is four-cornered, meaning thereby that the motion of the sun is characterised by four cardinal points: the two solstices and the two equinoxes. The year-long rites list a total of 180 days before the solstice and another 180 days following the solstice. Since this is reckoning by solar days, it is not clearly stated how the remaining four or five days of the year were assigned. But this can be easily inferred.

Note that the two basic days in this count are the visuvant (summer solstice) and the mahavrata day (winter solstice), which precedes it by 181 days in the above counts. Therefore, even though the count of the latter part of the year stops with an additional 180 days, it is clear that one needs another four or five days to reach the mahavrata day in the winter. This establishes that the division of the year was in the two halves of 181 and 184 or 185 days. Corroboration of this is suggested by evidence related to an altar design from the Satapatha Brahmana.

The altar represents the path of the sun around the earth. The middle point, which represents the earth and the atmosphere, is at a slight offset to the centre. This fact, and the fact that the number of bricks in the outer ring are not symmetrically placed, shows that the four quarters of the year were not taken to be symmetric.

This inequality would have been easy to discover. The Indians used the reflection of the noon-sun in the water of a deep well to determine the solstice days. If one assumes that the two halves of the year are directly in proportion to the brick counts of 14 and 15 in the two halves of the ring of the sun, this corresponds to day counts of 176 and 189. This division appears to have been for the two halves of the year with respect to the equinoxes if we note that the solstices divide the year into counts of 181 and 184.

The apparent motion of the sun is the greatest when the earth is at perihelion and the least when the earth is at aphelion. Currently, this speed is greatest in January. The interval between successive perihelia, the anomalistic year, is 365.25964 days, which is 0.01845 days longer than the tropical year on which our calendar is based. In 2,000 calendar years, the date of the perihelion advances almost 35 days; in 1,000 years, it advances almost a half-year (175 days). This means that the perihelion movement has a cycle of about 20,000 years.

In the first millennium BC, the earth was at perihelion within the interval prior to the winter solstice. Thus, during this period, the half of the year from the summer solstice to the winter solstice would have been shorter than the half from the winter solstice to the summer solstice. This is just the opposite of what is described in the rites of the Brahmanas.

It is interesting that the Greeks discovered the asymmetry in the quarters of the year about 400 BC. Modern calculations show that at this time, the four quarters of the year starting with the winter solstice were 90.4, 94.1, 92.3 and 88.6 days long. The period from the winter solstice to the summer solstice was then 184.5 days and the perihelion occurred in mid-to-late October.

The count of about 181 days from the winter to the summer solstice would be true when the perihelion occurs before the summer solstice. This will require it to move earlier than mid-to-late June and no earlier than mid-to-late December. In other words, compared to 400 BC, the minimum number of months prior to October is four, and the maximum number of months is 10. This defines periods which are from 6,850 years to 17,150 years prior to 400 BC.

These periods appear too early to be considered plausible, and this may reflect the fact that measurements in those times were not very accurate. Nevertheless, it means that the first millennium BC for the rites of the Brahmanas, as has been assumed by colonial historians, is absolutely ruled out.

Since the Satapatha Br has lists of teachers that go through more than fifty generations, we know that the period of the Brahmanas was a long one, perhaps a thousand years. To be as conservative as possible, we propose the period 2000-1000 BC as reasonable for these texts. The Vedic Samhitas should now be assigned to the earlier fourth and third millennia BC. It is significant that the dating of the second millennium BC is consistent with the recent archaeological figures.

The stages of ancient Indian astronomy

Our understanding of the Indian astronomy is undergoing a major shift. More than a hundred years ago, Burgess saw Indians as the originators of many of the notions that led to the Greek astronomical flowering. This view slowly lost support and then it was believed that Indian astronomy was essentially derivative and it owed all its basic ideas to the Babylonians and the Greeks.

It was even claimed that there was no tradition of reliable observational astronomy in India. Using statistical analysis of the parameters used in the many Siddhantas, Billard showed that the Siddhantas were based on precise observations, and so the theory of no observational tradition in India was wrong. Since then, it has been found that Vedic books are according to an astronomical plan. Earlier, it was believed that the mahayuga/kalpa figure of 43,20,000, which occurs in the Siddhantas, was borrowed from the astronomy of the Babylonian Berossos (c 300 BC). But this is already an important astronomical number in the much earlier Satapatha Brahmana.

The reason why incorrect notions related to Indian astronomy have persisted so long is because the authors have been unfamiliar with a great mass of the literature. It is also being recognised that the Siddhantic astronomy has features which are unique to India and it represents an independent tradition. Thurston says:

It is not clear that Aryabhatta was the originator of the idea of the rotation of the earth. It appears that the rotation of the earth is inherent in the notion that the sun never sets that we find in the Aitreya Brahmana 2.7:

One way to visualise it is to see the universe as the hollow of a sphere so that the inversion of the sun now shines the light on the world above ours. But this is impossible since the sun does move across the sky during the day, and if the sun doesn’t set or rise, it doesn’t move either. Clearly, the idea of “inversion” denotes nothing but a movement of the earth.

By our study of the early Vedic sources, we are getting into the position of understanding the stages of development of the earliest astronomy. After the Rigvedic stage comes the period of the Brahmana. This is followed by Lagadha’s astronomy. The last stage is early Siddhantic and early Puranic astronomy.

These four stages are summarised below:

1. Rigvedic astronomy (c. 4000-2000 BC)

Motion of the sun and the moon, naksatras, planet periods. The start of this stage is a matter of surmise, but we have clues such as Vedic myths which have been interpreted to indicate astronomical events of the fourth millennium BC.

2. Astronomy of the Brahmanas (2000-1000 BC)

Astronomy represented by means of geometric altars; non-uniform motion of the sun and the moon; intercalation for the lunar year; “strings of wind joined to the sun.”

3. Vedanga Jyotisa (c 1300 BC) [Lagadha]

The text that has come down to us appears to be of a later era. Being the standard manual for determination of the Vedic rites, Lagadha’s work must have served as a “living” text where the language got modified to a later form.

4. Early Siddhantic and early Puranic (1000 BC - 500 AD)

Here, our main sources are the Sulbasutras, the Mahabharata, the early Puranas and other texts. Further development of the sıghrocca and mandocca cycles, the concepts of kalpa.

It is significant that these stages are well prior to the rise of mathematical astronomy in Babylonia and in Greece. The concepts of the sıghrocca and mandocca cycles indicate that the motion of the planets was taken to be fundamentally around the sun, which, in turn, was taken to go around the earth.

The mandocca, in the case of the sun and the moon, is the apogee, where the angular motion is the slowest, and in the case of the other planets it is the aphelion point of the orbit. For the superior planets, the sıghrocca coincides with the mean place of the sun, and in the case of an inferior planet, it is an imaginary point moving around the earth with the same angular velocity as the angular velocity of the planet around the sun; its direction from the earth is always parallel to the line joining the sun and the inferior planet.

The mandocca point serves to slow down the motion from the apogee to the perigee and speed up the motion from the perigee to the apogee. It is a representation of the non-uniform motion of the body, and so it can be seen as a direct development of the idea of the non-uniform motion of the sun and the moon.

The sıghrocca maps the motion of the planet around the sun to the corresponding set of points around the earth. The sun, with its winds that hold the solar system together, is, in turn, taken to go around the earth. The antecedents of this system can be seen in the earlier texts. SB 4.1.5.16 describes the sun as puskaramadityo, “the lotus of the sky.” SB 8.7.3.10 says:

This suggests a central role to the sun in defining the motions of the planets, and ideas such as these must have ultimately led to the theory of the sıghrocca and the mandocca cycles.

Concluding remarks

The theory that the sun was the “lotus” [the central point] of the sky and that it kept the worlds together by its “strings of wind” gave rise to the heliocentric tradition in India mentioned by Thurston. The offset of the sun’s orbit evolved into the notion of mandocca, and the motions of the planets around the sun were transferred to the earth’s frame through the device of the sıghrocca.

The continuing analysis of the astronomical references in the Brahmanas has made it clear that the theory that the Siddhantic astronomy was somehow derived from the Babylonians and the Greeks is wrong. What is emerging from texts that are anterior by any reckoning, to the eras of astronomical advance in Babylonia or in Greece, is that astronomical ideas developed in India in stages and these stages can be seen in different layers of the Vedic texts, the Brahmanas and the Vedanga Jyotisa.

The evidence of the altar confirms that the year was divided into two parts: winter solstice to summer solstice being equal to 181 days, and midsummer-to-midwinter of 184 or 185 days. This, in turn, means that the Brahmana rites could not belong to the first millennium BC.

This conclusion is of the greatest significance for the chronology of the Vedic texts, and it invalidates the chronology popularised by Max Muller. This work supports the thesis that the Vedic and Harappan periods were identical.

References and Notes

1. Muller, Max, A History of Ancient Sanskrit Literature. Williams and Norgate, London, 1860; Eggeling, J (tr), The Satapatha Brahmana Motilal Banarsidass, Delhi, 1988 (1882-1900). For an important view which ascribes a much greater antiquity to the Vedic literature, see Winternitz, M A History of Indian Literature. Oriental Books, New Delhi, 1927 (1907).

2. Kuppanna Sastry, T S, Vedanga Jyotisa of Lagadha. Indian National Science Academy, New Delhi, 1985.

3. Eg, Kramrisch, S, The Presence of Siva. Princeton University Press, Princeton, 1981, pages 42-43.

4. de Santillana, G and von Dechend, H, Hamlet’s Mill: An Essay on Myth and the Frame of Time. Gambit, Boston, 1969.

5. Frawley, D, Indian Journal of History of Science, 1994, 29, 495-506.

6. Kak, S C, Mankind Quarterly, 1992, 33, 43-55.

7. Kak, S C, Vistas in Astronomy, 1993, 36, 117-140.

8. Kak, S C, Indian Journal of History of Science, 1993, 28, 15-34. 9. Kak, S C, Current Science, 1994, 66, 323-326.

9. Kak, S C, The Astronomical Code of the Rgveda. Aditya, New Delhi, 1994.

10. Kak, S C, Puratattva: Bulletin of the Indian Archaeological Society, 1994-95, 25, 1-21.

11. Kak, S C, Quarterly Journal of the Royal Astronomical Society, 1995, 36, 385-396.

12. Kak, S C, Quarterly Journal of the Royal Astronomical Society, 1996, 37, 709-715.

13. Bakliwal, P C and Grover, A K, Rec. Geol. Survey of India, 1988, 116, 77-86.

14. Possehl, G and Raval, M H, Harappan Civilization and Rojdi. E J Brill, Leiden, 1989.

15. Francfort, H P, Eastern Anthropologist, 1992, 45, 87-103.

16. O’Neil, W M, Early Astronomy. Sydney University Press, Sydney, 1986, pages 56-57.

17. Feuerstein, G, Kak, S C, and Frawley, D, In Search of the Cradle of Civilization. Quest Books, Wheaton, 1995.

18. Burgess, E. (tr.) The Surya Siddhanta. Delhi: Motilal Banarsidass, 1989 (1860); see also Indian Journal of History of Science, 20, 1985, and van der Waerden, B L, Journal for the History of Astronomy, 11, 1980, 50-58.

19. Billard, R, L’Astronomie Indienne. Ecole Francaise d’Extreme Orient, Paris, 1971.

20. van der Waerden, B L, Centaurus, 24, 1980, 117-131.

21. Thurston, H, Early Astronomy. Springer-Verlag, New York, 1994, page 188.

23. Kak, S C, Mankind Quarterly, 1992, 32, 195-213; Singh, B, The Vedic Harappans. Aditya, New Delhi, 1995. For a review of the problem of identity, see Lal, B B, The Earliest Civilization of South Asia. Aryan Books International, New Delhi, 1997, pages 281-287.