The Bhagavata goes on to liken the flat earth to a fully bloomed Lotus, and like the receptacle at its centre, it says abode of the gods, Meru (or Sumeru) is situated at the centre of Earth, raising tall reaching for the skies. The Jambu dwip, the central land mass, on which mount Meru firmly rests, is surrounded by seven concentric circles of oceans, each separated by seven circular land masses. The Puran compute the height of Meru mountain to be eighty-four thousand Yojanas above ground level. These “oceans” as it is stated in Bhagavata, are further described as made of brine, nectar, milk, butter, yoghurt and so on. There are also elaborate descriptions of pathal-log, netherworlds beneath the earth, where huge serpents, demons, divine beings and gods live (Bhagavata Purana: Canto 5, Ch 16: 5-30; Ch 20, 24, 25). Similar descriptions are also found among others, in Vishnu and Mthsya Puran.
In this conception, the solar orb is situated a hundred thousand yojana from the Earth; and that of the Moon an equal distance from the Sun. At the same interval above the Moon occurs the orbit of all the lunar constellations – or Nakshatras. The planet Budha (Mercury) is two hundred thousand leagues above the lunar mansions. Śukra (Venus) is at the same distance from Mercury. Angáraka (Mars) is as far above Venus, and the priest of the gods (Vrihaspati, or Jupiter) as far from Mars: while Saturn (Sani) is two hundred and fifty thousand leagues beyond Jupiter. The sphere of the seven Rishis (Ursa Major) is a hundred thousand leagues above Saturn; and at a similar height above the seven Rishis is Dhruva (the Pole-star), the pivot or axis of the whole planetary circle.
All the planets are fastened to Dhruva by aerial cords. The orbs of all the planets, Nakshatras, and stars are attached to Dhruva, and travel accordingly in their proper orbits, being kept in their places by their respective bands of air called Pravaha. As many as are the stars, so many are the chains of air that secure them to Dhruva; and as they turn round, they cause the Pole-star also to revolve. That is, Dhurva is like a spindle, and hence all the planets and stars move above it makes the Dhurva to also revolve. Therefore, planets travel round, suspended by cords of air, which are circling around a (whirling) centre.
Scholars dispute, but according to one estimate, one yojan is about ten km and hence the supposed height of Meru is about which would amount to about 8,40,000 km. The size of the circular disc, according to Puran, is about fifty crores of yojanas in extent, implying that the diameter of Earth is about 750 crore km, which approximately equals the size of Neptune’s orbit. The average distance of Moon from Earth is just 3,84,400, and the diameter of Earth is just about 12000 km, and thus the whole schema is but a fantastic speculation, is clearly evident. This speculative cosmology, unsurprisingly, is inadequate for mathematical prediction of the motions of the heavenly bodies.
Day, night and eclipses according to Puran
The chariot of the sun whirls around Mt Meru, like the circumference of the wheel of a potter. This orbit of Sun around the Mt Meru results in alternating day and night phenomena states the Purans. Further, as Moon is placed beyond Sun, it can never come in between Earth and Sun and thus cannot be the cause of the solar eclipse. In like manner, Earth being a flat circular disc, situated bottom most in the pyramid of cosmos, cannot cast a shadow on the surface of the Moon.
Vishnu Puran has a fantastic story of Samudra Manthan (Churning of Ocean) and the Rahu- Ketu mythology to explain the eclipses. In fact, stray references can be traced back to Rig Veda wherein a fantastic story of snake-demon (Asur) devourer Sun is found. According to its earliest Rig Vedic version, Svarbhanu, the asura, pierced the Sun with darkness so completely that the bewildered inhabitants on Earth did not know where they were standing. Then Atri, with the power of his prayer, caused Svarbhanu’s magic arts to disappear and restored the Sun to its brilliance.
Pancavimsa Brahmana, of which a typical description runs as follows: ‘The demon Svarbhanu struck the sun with darkness; the Gods did not discern it; the sun was hidden as it was by darkness; they resorted to Atri; Atri repelled its darkness by the bhasa. The part of the darkness he first repelled its darkness he first repelled became a black sheep, what (he repelled) the second time (became) a silvery (sheep), what (he repelled) the third time (became) a reddish one, and with what (arrow) he set free its original appearance (colour), that was a white sheep.’ The interesting feature of the above passage is the detailed observation of the change of colour in the sun’s disc during the progress of an eclipse. In itself the story is fantastic and fascinating; the difficulty arises only when these myths are taken literally and as correct description of the eclipse.
Orthodoxy and Āryabhaṭa
Earth is spherical in nature, it rotates about its axis, resulting in day and night, eclipses are just shadow play, with Moon’s shadow falling on Earth resulting in solar eclipse and Earth shadow falling on moon resulting in lunar eclipse are some of his seminal contributions. All of these are high-school physics today. However in his time, and for many centuries, Āryabhaṭa was ridiculed and his ideas derided. While scientific dispute and doubt are conventional and are to be respected and appreciated, those who mocked him castigated him for going against the tenets of Puran and Vedic claims.
The theory of the Earth’s daily rotation about its axis resulting in day and night were severely criticised among others by Varahamihira and Brahmagupta (628 A.D.). Varahamihira in Pancasiddhanthaika “others say that earth, as if on a potters wheel rotates and not the constellations. If that were so how could hawks etc. come back to their nests. Moreover of the Earth rotated once a day bees geese etc. would be driven to the west. If the earth moved slowly how could it complete a revolution in one day” Even an accomplished astronomer of Brahmagupta refutes by saying that if the earth rotted nobody could come back to his own abode; things standing would fall. Lalla (eight century) says in Sisydhivrddhida that “if the earth rotated.. arrows thrown towards the sky would fall towards the west, the clouds would be moving towards the west…” Somesvara, a commentator, misinterpreted the above verses as conveying the contrary sense to fit what Aryabhata was claiming with that of the theological cosmology of Puran. While Aryabhata argued that Earth rotates from west to east resulting in the apparent diurnal motion of Sun and stars from east to west, Somesvara asserts that it is a false view. “For, if the Earth had a motion, the world would have been inundated by the oceans, the tops of the trees and castles would have disappeared, having been blown away by the storm caused by the velocity of the Earth, and the birds etc. flying in the sky would never have returned to their nests. So, there exists not a single trace of the Earth’s motion.” Aryabhata’s claim “pranenaiti kalam bhur” was changed to “pranenaiti kalam bham” by later day commentators, including Bhaskara, in order to eliminate Aryabhata’s theory of the rotation of the Earth. Bhur, would imply Earth is rotating; and bham would imply it is the Sun and the stars that go around the Earth every day. However, it is noteworthy that Prthudaka (860 A.D.) in his commentary on the Brahma-sphuta-siddhanta, states that astronomer such as Bharamagupta who misinterpreted Aryabhata was afraid of public opinion which was against the motion of Earth, and states that Aryabhata was correct in claiming Earth was rotating on its axis.
Varahamihira, the author of the famous astronomical treatise Pancasiddhantika, was cautious and tried to reconcile the unfounded Puranic myth with the scientific knowledge expounded by Aryabhata. He agreed with Aryabhata that solar eclipses are caused when the Moon obstructed the face of Sun and Earth’s shadow falling on Moon causes a lunar eclipse; however, he argued that at the time of eclipse, mythical demon, Rahu (or Ketu) is also present near the eclipsed Sun/Moon, and it is necessary to perform traditional rites as expounded in the Puranas and scriptures.
Brahmagupta went one step further and criticised Āryabhaṭa I, Srisena, Visnucandra, Lata and Pradyumna for their views that Earth is spherical and eclipses are caused due to shadows of Earth and Moon falling on each other, in his Brahmasphuta-Siddhanta. In his Brahmasiddhanta he says, “Some people think that the eclipse is not caused by the Head (that is Ragu/Ketu). This, however, is a foolish idea, for it is he in fact who eclipses, and the generality of the inhabitants of the world say that it is the Head that eclipses. The Veda, which is the word of God from the mouth of Brahman, says that the Head eclipses. On the contrary. Varahamihira, Shrishena, Aryabhata and Vishnuchandra maintained that the eclipse is not caused by the Head, but by the Moon and the shadow of the Earth. The earth’s shadow does not obscure the moon, nor the moon the sun, in an eclipse. Rahu, standing there equal to them in size, obscures the moon and the sun.”
Thus we can see that under the pressure of orthodoxy, ancient Indian scientists were often obliged to concede to certain favourite myths of the vested interests, in spite of knowing full well that the scientific truths they arrive at are entirely incompatible with these myths.
Theological cosmology and scientific astronomy in Indian tradition
The sacred cosmology of the Puran and the mathematical models of the Siddhanta clash in many important respects and several siddhantic texts of the first and early second millennium issued open contradictions of Puranic assertions. Āryabhaṭa’s siddhantic model of the cosmos substituted mathematical and physical truth criteria for the arguments from authority on which Puranic cosmology was based. The spherical earth notion seems to go against our everyday experience and appear outlandish. Aryabhata says, “those who know calculation say [that] a hundredth part of the circumference [of the earth] is seen as flat. So the earth appears flat to this extent; it is just meant in that way” to show that how Earth can be a sphere, although it appears to be flat in our everyday experience. One can readily note that he and other Siddanthic scholars defended their claims essentially on the grounds that it was mathematically effective. The fact that “calculation” or mathematical prediction agreed with observed result (or could be made to agree with it, in the case of the apparent flatness of the spherical earth) was an argument in favour of the predictive model’s reality. The Puranic model revealed by sacred texts and the siddhantic model derived from calculation and observation soon developed contradictions, and the remarks of Aryabhata makes it amply clear which side an astronomer was supposed to be on.
Brahmagupta’s siddhanta about 130 years later explicitly challenged the Puranic assumption that the moon is farther away than the sun: “If the moon [were] above the sun [as the Puran, as indicate], how would [its] power of increase and decrease in brightness, etc., [be produced] from calculation [of the position of] the moon? The closer half would always be bright.
In the middle of the eighth century, an astronomer named Lalla devoted an entire chapter (bluntly entitled “Errors”) of his own siddhanta to refuting various assumptions of Puran. The chapter titled “errors” contradicted Puranic cosmology such as The illuminated portion of the Moon decreases because it is being sucked by the gods; The earth is plane like a mirror; The night comes when the mountain Meru covers the Sun; Rahu, a mythical demon or a snake is the cause of eclipses and so on. Lala questioned the Puranic supporters, “If your opinion is that a demon (Ragu/Ketu) invariably devours [the moon or sun] employing magic, how is it [that the event can be] found by calculation? And how [is it that there is] no eclipse except [at] new or full moon? Eclipses, conjunctions of planets, risings, the appearance of the lunar crescent, the rule for [computing] the shadow at a given [time]—the solution of all five is accurate [when found] employing the [siddhantic] size of the earth. So how could it be [as] large [as the Puran say]?”
If India could boast of so many innovations in the area of astronomy, why then was Aryabhata ridiculed and derided, even by accomplished scholars such asVarahamihira and Brahmagupta? Researchers say, the demise of astronomical tradition in India is linked to the rise of orthodoxy during the 7th and 8th century. The time of Āryabhaṭa that is, Gupta period, was one of assimilation, tolerance and broadmindedness. Universities like Nalanda, Nagarjundakhonda and Vikramasila, were founded and patronised. Poet Kalidasa lived during that time. Historians point out that this period was the height of Buddhist and Hindu architecture. It was a period of openness to global ideas, that it was characterised by magnificent achievements in religious-philosophical debates among Jains, Buddhists and Hindus. However, all these came to an end when the religious orthodoxy took hold of the social life subsequent to Gupta period. In particular, theManu Smriti, which had a strict injunction against heretical thinking, became influential. Caste rules, rules of high and low, rules of untouchability and inequality all were made more and more strict. All knowledge and science were made more secret, secluded, hidden and concealed, and every new thought and invention were opposed. Even Ayurvedic vaids were considered ‘polluted’ and downgraded in the caste hierarchy. Astronomers or so-called jyotirvids were denounced and were declared ‘polluted’. Manu Smrithi condemned and prohibited scientists from being called to yagnas, mahadanas and shraadhas. Further, the Brahmins changed the meaning of the word jyotirvidya, which now meant those who study the ‘effects’ of stars on human beings contrary to the original meaning of study of stars, and themselves became daivaidnyas — the knower of fate. Thus, astronomers had to fall in line and bow their head towards blind faith and scriptures. In the name of faith, myths of the Purans and incipient ideas of earlier culture were taken as the final word and scientific progress was stifled. In fact, subsequently, Indian astronomical tradition suffered a serious setback and did not recover for many centuries. Thus we have Varahamira, who tried to make peace between science of Aryabhata and the puranic myths, and later Brahamagupta went to the extent of negating science in preference to myth. However, it should be noted that even Brahamagupta used the formulas and methods of Aryabhata in the second part of his book when he talks about the computation of eclipses.
The sufferings of Galileo, Bruno in the hands of faith-based orthodoxy is well known. Orthodoxy and fundamentalism have always been an impediment to the growth of science and knowledge. Closer at home, one of the greatest ancient Indian astronomers, Āryabhaṭa had to meet a similar fate at the hands of Hindu orthodoxy foregrounding revelations and faith over reason and scientific evidence. The contemporary developments that foreground faith over evidence and reason would take us once again to dark ages.