Reproduction, Sex and Heredity of plants Ancient Indian literature also deals with sex, genetics, and reproduction of plants by fruits, seeds, roots, cuttings, graftings, plant apices and leaves. Buddha Ghosa, in his Sumangala-vilasini, a commentary on the Digha Nikaya, describes some of these methods under such terms as mula-vija (root seed), khandabija (cuttings), phaluvija (joints), agravija (budding) and bija-bija (seed). Atharvaveda and Arthasastra describe the propagation by seed (bija-bija or vijaruha) and bulbous roots (kandavija), respectively. The method of cutting (skandhavija) is described in the Arthasastra, Brhatsamhita and Sumangala-vilasini in the case of sugar cane, jackfruit, blackberry, pomegranate, vine, lemon tree, asvattha (Ficus religiosa), nyagrodha (Ficus bengalensis), udumbara (Ficus glomerata) and several others. Some ideas related to sexuality in plants are noticeable in the Harita and Charak Samhitas. Charak recognized male and female individuals in the plant called Kutaja (Hollerhina antidysenterica), and the male categories of plants bearing white flowers, large fruit and tender leaves and the female categories characterized by yellow flowers, small fruits, short stalk, etc. The Rajanighantu mentions the existence of male and female plants in the plant Ketaki (Pandanus odoratissimus). The male plant is called sitaketaki, and the female is called svarna ketaki. Regarding heredity, Charaka and Susruta mention that the fertilized ovum contains in miniature all the organs of the plants, for example the bamboo seed containing in miniature the entire structure of the bamboo tree, and further that the male sperm cell have minute elements derived form each of its organs and tissues. http://www.infinityfoundation.com/mandala/t_es/t_es_tiwar_botany_frameset.htm
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Monday, July 27, 2015
Baku Ateshgah or “Fire Temple” is an ancient Hindu religious temple dedicated to Jwala Ji in Surakhani, a suburb of greater Baku, Azerbaijan. It was initially thought to be a Zoroastrian fire worship place as “Atash” is the Persian word for fire.Four holy elements of local people belief were: ateshi (fire), badi (air), abi (water), and heki (earth). A pentagonal complex, which has a courtyard surrounded by cells for monks and a tetrapillar-altar in the middle, was built during the 17th and 18th centuries but temple ceased to be worshiped after 1883 with the installation of petroleum plants (industry) at Surakhany. The complex was turned into a museum in 1975. Fire is considered sacred in both Indo-Iranian branches of Hinduism and Zoroastrianism (as Agni and Atar respectively),and there has been debate on whether the Atashgah was originally a Hindu structure or a Zoroastrian one. The trident mounted atop the structure is usually a distinctly Hindu sacred symbol (as the Trishul, which is commonly mounted on temples) and has been cited by Zoroastrian scholars as a specific reason for considering the Atashgah as a Hindu site. There are several inscriptions on the Ateshgah. They are all in either Sanskrit or Punjabi, with the exception of one Persian inscription that occurs below an accompanying Sanskrit invocation to Lord Ganesha and Jwala Ji. Although the Persian inscription contains grammatical errors, both the inscriptions contain the same year date of 1745 Common Era (Samvat/संवत 1802/१८०२ and Hijri 1158/١١٥٨). Taken as a set, the dates on the inscriptions range from Samvat 1725 to Samvat 1873, which corresponds to the period from 1668 CE to 1816 CE. One press report asserts that local records exist that state that the structure was built by the Baku Hindu traders community around the time of the fall of the Shirvanshah dynasty and annexation by the Russian Empire following the Russo-Persian War (1722–1723). The inscriptions in the temple in Sanskrit (in Nagari Devanagari script) and Punjabi (in Gurmukhi script) identify the site as a place of Hindu and Sikh worship,and state it was built and consecrated for Jwala Ji, the modern Hindu fire deity. Jwala (जवाला/ज्वाला) means flame in Sanskrit . In his Travels Outside Bombay, Modi observed that “not just me but any Parsee who is a little familiar with our Hindu brethren’s religion, their temples and their customs, after examining this building with its inscriptions, architecture, etc., would conclude that this is not a [Zoroastrian] Atash Kadeh but is a Hindu Temple, whose Brahmins (priests) used to worship fire (Sanskrit: Agni).” There is a famed shrine to Jwala Ji in the Himalayas, in the settlement of Jawalamukhi, in the Kangra district of Himachal Pradesh, India to which the Atashgah bears strong resemblance and few scholars have stated that some Jwala Ji devotees used to refer to the Kangra shrine as the ‘smaller Jwala Ji‘ and the Baku shrine as the ‘greater Jwala Ji‘. In 1876, James Bryce visited the region and found that “the most remarkable mineral product is naphtha, which bursts forth in many places, but most profusely near Baku, on the coast of the Caspian, in strong springs, some of which are said to always be burning.” Without referencing the Atashgah by name, he mentioned of the Zoroastrians that “after they were extirpated from Persia by the Mohammedans, who hate them bitterly, some few occasionally slunk here on pilgrimage” and that “under the more tolerant sway of the Czar, a solitary priest of fire is maintained by the Parsee community of Bombay, who inhabits a small temple built over one of the springs“. The fire was once fed by a vent from a subterranean natural gas field located directly beneath the complex, but heavy exploitation of the natural gas reserves in the area during Soviet rule resulted in the flame going out in 1969. Today, the museum’s fire is fed by mains gas piped in from Baku city.
Veda Vyasa & the question of untouchability *********************************************Veda Vyasa is a legendary Hindu sage, whose very name is synonymous to Hindus with knowledge. According to traditional Hindu accounts, he lived at the end of the Dwapara Yuga and early Kali Yuga (the date for the beginning of the Kali Yuga is 3102BC). Veda Vyasa is accredited with compiling the Vedas and writing the Brahma Sutras, which are one of the three great authoritative Hindu philosophical texts. He was also the recorder/writer of the earliest form of the Mahabharata (which was originally called the ‘Jaya’). The followers of Veda Vyasa (the Vyasas or ‘compilers’) carried out the compilation of the Puranas. His birthday is celebrated as ‘Guru Purnima’ – one of the most sacred days in the Hindu calendar, which is the day when teachers are honored. A popular saying about Veda Vyasa goes: ‘Vyasocchishtasam jagat sarvam’ meaning that so great was the learning of Rishi Veda Vyasa, that even his voluminous writings represent only the periphery of his knowledge. Virtually every Hindu sampradaya (order) traces their lineage to him, and wherever knowledge is propagated and respected is called a Vyaspeeth – Vyasa’s throne. Yet had Veda Vyasa, the compiler of the Vedas, lived in the later degenerate and perverted age of Hindu society, he may well have been considered an untouchable and not even allowed to touch the Vedas! His mother (Satyavati) used to sell fish to make a living, and in many parts of Hindu society in its later period of caste insanity this would have made him an untouchable. Yet Vyasa is considered by all Hindus to be the very epitome of wisdom! This is just one of many examples (another being Valmiki – author of the Ramayana) that shows that the terrible caste rigidity of Hindu society that we have seen at some points in our past, and which still persists today in some parts, was definitely not originally the state of things, and certainly does not represent the true spirit of Hinduism.
In Theravada Buddhism, Vishnu = Upalvan In Mahyana Buddhism, Shiva = Demchog(Chakrasamvara Tantra) Upulvan is also known Guardian God of Buddhism or Protector of Buddhism. Demchog is same as Shiva because According to Mahayana Buddhism, Mt.Kailash is residence of Demchog. -Kunal Modi
Hindus have 33 crore gods -explanation
**************************************************33 divinities are mentioned in the Yajur-veda, Atharva-veda, occurs in the Parsi scriptures of Avesta as well.The expression trayastrimsa deva is found in the list of classes of gods in Sanskrit Buddhist texts like the Divyavadana and Suvarnaprabhasa-sutra.The word koti in ‘trayastrimsati koti’ does not mean the number '33 crore’ or '330 million’. Here koti means 'supreme’, pre-eminent, excellent, that is, the 33 'supreme’ divinities. It has been documented in Brihadaranyaka Upanishad Śākalya : “How many gods are there?” Yājñavalkya : “Three hundred and three.” Then he says, “Three thousand and three.” Śākalya : “Is this the answer that you give me to my question, how many gods are there? Three thousand and three; three hundred and three! Have you no other answer to this question?” Yājñavalkya : There are thirty-three gods. Śākalya : “All right!” (not satisfied with answer) …Tell me again properly; how many gods are there?“ Yājñavalkya : "Six are there.” Śākalya : “How many gods are there. Tell me again. Think properly.” Yājñavalkya : “Only three gods are there.” Śākalya : “How many gods are there? Tell again. Yājñavalkya : "Two gods are there.” Śākalya : “Tell again; how many gods are there?” Yājñavalkya : “One and a half gods” (Then he was very much upset) Śākalya : “What is this you say, one and a half gods. Tell again properly; how many gods are there?” Yājñavalkya : “One god is there,” Śākalya : “All these numbers that you have mentioned – three thousand and three, three hundred and three – what are these gods? Give the names of these gods, the deities.” Yājñavalkya : “All these three thousand and all that I mentioned – they are not really gods. They are only manifestations of the thirty-three. The thirty-three are the principal manifestations, and others are only their glories, radiances, manifestations, magnificences or forces, energies, powers.” Śākalya : “But what are these thirty-three?” Yājñavalkya : “The thirty-three gods are eight Vasus, eleven Rudras, twelve Ādityas, then Indra and Prajāpati – these make thirty-three gods.” Śākalya : “What are these Vasus which are eight in number?” Yājñavalkya : “Fire is one deity; earth is one deity; air is another; the atmosphere is one deity; the sun is one deity; the heaven is one deity; moon is one deity; the stars are one deity. These constitute eight groups” Śākalya : “Why do you call them Vasus?” Yājñavalkya : “Everything is deposited as it were in these constituent principles. Therefore, they are called Vasus.” Śākalya : “Who are the Rudras?” Yājñavalkya : “The ten senses and the mind make eleven. These are the Rudras.” Śākalya : “What are the twelve Ādityas, the suns?” Yājñavalkya : “They are twelve forces of the sun, takes away the vitality of people.” Śākalya : “Who is Indra? Who is Prajāpati?” Yājñavalkya : “The rain cloud can be called Indra. Sacrifice can be called Prajāpati.” Śākalya : “What do you mean by rain cloud?” Yājñavalkya : “By rain cloud I do not actually mean the cloud, but the lightning which is the embodiment of energy.”
Darbha (Desmotachya bipinnata) is a tropical grass considered a sacred material in Vedic scriptures and is said to purify the offerings during such rituals. Traditional tropical grass, Darbha, has been identified as an eco-friendly food preservative. This finding was evolved in a research study undertaken jointly by the Centre for Nanotechnology and Advanced Biomaterials (CeNTAB) and the Centre for Advanced Research in Indian System of Medicine (CARISM) of the SASTRA University, Thanjavur, under the supervision of Dr. P. Meera and Dr. P. Brindha respectively. At the time of eclipse, people place that grass in food items that could ferment and once the eclipse ends the grass is removed. A systematic research was conducted by the SASTRA University researchers, in which cow’s curd was chosen as a food item that could ferment easily. Five other tropical grass species, including lemon grass, Bermuda grass, and bamboo were chosen for comparison based on different levels of antibiotic properties and hydro phobicity. Electron microscopy of different grasses revealed stunning nano-patterns and hierarchical nano or micro structures in darbha grass while they were absent in other grasses. On studying the effect of various grasses on the microbial community of the curd, darbha grass alone was found to attract enormous number of bacteria into the hierarchical surface features. These are the bacteria responsible for fermentation of cow’s curd. During eclipse, the wavelength and intensity of light radiations available on the earth’s surface is altered. Especially, the blue and ultraviolet radiations, which are known for their natural disinfecting property, are not available in sufficient quantities during eclipse. This leads to uncontrolled growth of micro-organisms in food products during eclipse and the food products are not suitable for consumption. Darbha was thus used as a natural disinfectant on specific occasions, say researchers at SASTRA University. Further, the scientists say that darbha could be used as a natural food preservative in place of harmful chemical preservatives and the artificial surfaces mimicking the hierarchical nano patterns on the surface of darbha grass could find applications in health care where sterile conditions were required. This entire research was funded by the SASTRA University’s Research Fund.http://m.thehindu.com/news/cities/Tiruchirapalli/darbha-grass-a-natural-preservative/article7000098.ece/
ANCIENT INDIAN MATHEMATICS ********************************************* Despite developing quite independently of Chinese (and probably also of Babylonian mathematics), some very advanced mathematical discoveries were made at a very early time in India. Mantras from the early Vedic period invoke powers of ten from a hundred all the way up to a trillion, and provide evidence of the use of arithmetic operations such as addition, subtraction, multiplication, fractions, squares, cubes and roots. A 4th Century AD Sanskrit text reports Buddha enumerating numbers up to 1053, as well as describing six more numbering systems over and above these, leading to a number equivalent to 10421. Given that there are an estimated 1080 atoms in the whole universe, this is as close to infinity as any in the ancient world came. It also describes a series of iterations in decreasing size, in order to demonstrate the size of an atom, which comes remarkably close to the actual size of a carbon atom (about 70 trillionths of a meter). As early as the 8th Century BC, long before Pythagoras, a text known as the “Sulba Sutras” (or “Sulva Sutras”) listed several simple Pythagorean triples, as well as a statement of the simplified Pythagorean theorem for the sides of a square and for a rectangle (indeed, it seems quite likely that Pythagoras learned his basic geometry from the “Sulba Sutras”). The Sutras also contain geometric solutions of linear and quadratic equations in a single unknown, and give a remarkably accurate figure for the square root of 2, obtained by adding 1 + 1⁄3 + 1⁄(3 x 4) + 1⁄(3 x 4 x 34), which yields a value of 1.4142156, correct to 5 decimal places. As early as the 3rd or 2nd Century BC, Jain mathematicians recognized five different types of infinities: infinite in one direction, in two directions, in area, infinite everywhere and perpetually infinite. Ancient Buddhist literature also demonstrates a prescient awareness of indeterminate and infinite numbers, with numbers deemed to be of three types: countable, uncountable and infinite. Like the Chinese, the Indians early discovered the benefits of a decimal place value number system, and were certainly using it before about the 3rd Century AD. They refined and perfected the system, particularly the written representation of the numerals, creating the ancestors of the nine numerals that (thanks to its dissemination by medieval Arabic mathematicans) we use across the world today, sometimes considered one of the greatest intellectual innovations of all time. The Indians were also responsible for another hugely important development in mathematics. The earliest recorded usage of a circle character for the number zero is usually attributed to a 9th Century engraving in a temple in Gwalior in central India. But the brilliant conceptual leap to include zero as a number in its own right (rather than merely as a placeholder, a blank or empty space within a number, as it had been treated until that time) is usually credited to the 7th Century Indian mathematicians Brahmagupta - or possibly another Indian, Bhaskara I - even though it may well have been in practical use for centuries before that. The use of zero as a number which could be used in calculations and mathematical investigations, would revolutionize mathematics. Brahmagupta established the basic mathematical rules for dealing with zero: 1 + 0 = 1; 1 - 0 = 1; and 1 x 0 = 0 (the breakthrough which would make sense of the apparently non-sensical operation 1 ÷ 0 would also fall to an Indian, the 12th Century mathematician Bhaskara II). Brahmagupta also established rules for dealing with negative numbers, and pointed out that quadratic equations could in theory have two possible solutions, one of which could be negative. He even attempted to write down these rather abstract concepts, using the initials of the names of colours to represent unknowns in his equations, one of the earliest intimations of what we now know as algebra. The so-called Golden Age of Indian mathematics can be said to extend from the 5th to 12th Centuries, and many of its mathematical discoveries predated similar discoveries in the West by several centuries, which has led to some claims of plagiarism by later European mathematicians, at least some of whom were probably aware of the earlier Indian work. Certainly, it seems that Indian contributions to mathematics have not been given due acknowledgement until very recently in modern history. Golden Age Indian mathematicians made fundamental advances in the theory of trigonometry, a method of linking geometry and numbers first developed by the Greeks. They used ideas like the sine, cosine and tangent functions (which relate the angles of a triangle to the relative lengths of its sides) to survey the land around them, navigate the seas and even chart the heavens. For instance, Indian astronomers used trigonometry to calculated the relative distances between the Earth and the Moon and the Earth and the Sun. They realized that, when the Moon is half full and directly opposite the Sun, then the Sun, Moon and Earth form a right angled triangle, and were able to accurately measure the angle as 1⁄7°. Their sine tables gave a ratio for the sides of such a triangle as 400:1, indicating that the Sun is 400 times further away from the Earth than the Moon. Although the Greeks had been able to calculate the sine function of some angles, the Indian astronomers wanted to be able to calculate the sine function of any given angle. A text called the “Surya Siddhanta”, by unknown authors and dating from around 400 AD, contains the roots of modern trigonometry, including the first real use of sines, cosines, inverse sines, tangents and secants. As early as the 6th Century AD, the great Indian mathematician and astronomer Aryabhata produced categorical definitions of sine, cosine, versine and inverse sine, and specified complete sine and versine tables, in 3.75° intervals from 0° to 90°, to an accuracy of 4 decimal places. Aryabhata also demonstrated solutions to simultaneous quadratic equations, and produced an approximation for the value of π equivalent to 3.1416, correct to four decimal places. He used this to estimate the circumference of the Earth, arriving at a figure of 24,835 miles, only 70 miles off its true value. But, perhaps even more astonishing, he seems to have been aware that π is an irrational number, and that any calculation can only ever be an approximation, something not proved in Europe until 1761. Bhaskara II, who lived in the 12th Century, was one of the most accomplished of all India’s great mathematicians. He is credited with explaining the previously misunderstood operation of division by zero. He noticed that dividing one into two pieces yields a half, so 1 ÷ 1⁄2 = 2. Similarly, 1 ÷ 1⁄3 = 3. So, dividing 1 by smaller and smaller factions yields a larger and larger number of pieces. Ultimately, therefore, dividing one into pieces of zero size would yield infinitely many pieces, indicating that 1 ÷ 0 = ∞ (the symbol for infinity). However, Bhaskara II also made important contributions to many different areas of mathematics from solutions of quadratic, cubic and quartic equations (including negative and irrational solutions) to solutions of Diophantine equations of the second order to preliminary concepts of infinitesimal calculus and mathematical analysis to spherical trigonometry and other aspects of trigonometry. Some of his findings predate similar discoveries in Europe by several centuries, and he made important contributions in terms of the systemization of (then) current knowledge and improved methods for known solutions. The Kerala School of Astronomy and Mathematics was founded in the late 14th Century by Madhava of Sangamagrama, sometimes called the greatest mathematician-astronomer of medieval India. He developed infinite series approximations for a range of trigonometric functions, including π, sine, etc. Some of his contributions to geometry and algebra and his early forms of differentiation and integration for simple functions may have been transmitted to Europe via Jesuit missionaries, and it is possible that the later European development of calculus was influenced by his work to some extent.
Thursday, July 23, 2015
The Vedas, Epics and Puranas of ancient India describe an interesting concept of time called Kaalachakra, the wheel of time. This wheel of time is conceived as having twelve spokes indicating twelve points of time measurement on the wheel of time. Close examination of the imagery reveals that this concept is related to the Yuga System and used for various kinds of time measurements in ancient India. The same wheel of time is used to measure hours in a day, months and seasons in a year and large units of time like Yugas, which appear like seasons lasting for thousands of years as part of the 25,776 years long "Great Year" resulting from the precession of Earth's Axis of Rotation.
The twelve spoked wheel of time (Kaalachakra). Twelve divisions are named with zodiac signs for easy comparison with Western Systems. The Pisces-Aquarius transition base-lined at 2012 CE
Motions of Sun
The twelve spoked wheel of time (Kaalachakra) is mentioned extensively in Rig Veda and other Vedas. Vedic seers used to make observations of the sky with this framework called the wheel of time in their mind. For this they closely observe the path of the sun through the sky and locate its position in the sky
Observations from the South and North of India
Close to Equator in Southern India, the Sun traverse a path close to celestial equator, rising in the east and setting in the west, reaching zenith at noon. Besides this daily motion, Sun also makes a pendulum like motion on an yearly basis moving northwards and southwards clearly observable in northern India, 35 degrees north of equator. Ancient Indian astronomers, which includes many Vedic seers in northern and southern India, knew very well the reasons for all these movements. They were aware that Earth is a sphere moving around sun in an year, with a tilted axis, where it rotates once a day and that the axis of rotation itself will make one turn in around 26,000 years.
Depth of Knowledge of Ancient Astronomers
They knew that daily motion of sun in the sky is due to the rotation of Earth on its axis. They knew that yearly pendulum like motion of Sun in the sky to north and south is due to the yearly revolution of Earth in its orbit around Sun with a tilted axis of rotation. All these motions are partially confined in a band of region in celestial sky around 20 degrees north and south of the celestial equator. This band is called zodiac. It resembles the wheel of time (Kalachakra) and is one of the many aspect of the wheel of time, the other one being the orbit of the celestial pole in the sky. The zodiac is the region where the sun, moon and the five visible planets apparently wander in the sky of Earth. This region was of tremendous important for the ancient astronomers. It was divided into 12 constellations or regions where easily recognizable configurations of well known stars were defined. The twelve constellations were thus defined as stellar formations in the shape of fish, ram, bull, crab, lion, scorpion etc. These 12 constellations are Pisces (the fish), Aries (the ram), Taurus (the bull), Gemini (the twins), Cancer (the crab), Leo (the lion), Virgo (the virgin), Libra (the scales), Scorpio (the scorpion), Sagittarius (the archer), Capricorn (the sea animal) and Aquarius (the pot bearer). Each of these regions span around 30 degrees of the Zodiac wheel. These 12 regions are also called the 12 zodiacal signs and is one of the basis of astrology besides being fundamental to ancient astronomy.
The ancient astronomers also knew that the axis of rotation itself is slowly rotating, something which require many thousands of years of careful observation. All of these developments are already discussed in the article named Yugas.
The Daily Motion and Temperature Variations
Sun moves from eastern horizon to western horizon reaching zenith at noon. During zenith position sun's rays reach us perpendicularly and we feel maximum heat. During morning and evening sun's rays reach us with an inclination so that it travel a longer distance through atmosphere which dissipate much heat before it reach us. This changes create a smaller version of seasonal changes that we observe through out the year.
Yearly Motion and Yearly Seasons
The various seasons are the result of yearly motion of Sun in the terrestrial sky.
Uttarayana and Dakshinayana
The movement of Sun in the sky to the north is called Uttarayana. The movement of Sun in the sky to the south is called Dakshinayana. These apparent movements are due to the combined effect of Earth's motion in its orbit around Sun and due to the 23.5 degree tilt of Earth's Axis of Rotation. These motions are linked to the four important days of the year viz. Winter Solstice, Vernal Equinox, Autumnal Equinox and Summer Solstice. Uttarayana (northward motion of sun) commence after Winter Solstice day when northern hemisphere observe longest night. During Uttarayana at one point day and night becomes equal and that is Vernal Equinox day. Uttarayana ends at Summer Solstice day when the duration of night becomes lowest. After this Dakshinayana (southward motion of sun) begins. During Dakshinayana at one point day and night becomes equal again and that day is Autumnal Equinox day.
The Four Corners of the Sky
The position of sun against the background of stars in the sky, during all these four days viz. Winter Solstice, Vernal Equinox, Autumnal Equinox and Summer Solstice is considered as four crucial points in the zodiac. These four points constitute "the four corners of the sky". They are figuratively praised in the scriptures as the four great supports of the sky and as the four pillars that uphold the sky, due to obvious reasons.
The Six Seasons
When Sun moves to south and reach the southern most point in the celestial sky, Sun's rays reach earth obliquely. This reduces the amount of heat reaching northern hemisphere, due to reflection and refraction of sun's rays in the atmosphere. This generate a cold climate in northern hemisphere and causing winter season. Similarly when the Sun moves to north and reach the northern most point in the celestial sky, sun's rays fall in northern hemisphere perpendicularly causing maximum heat in northern hemisphere and thus summer season. In this way all the seasons are resulted from the motion of Sun and due to the resultant change in the energy distribution and energy flow in Earth's atmosphere.
The seasons are six in numbers (Shad Rtu, six seasons):- Vasanta (Spring:- February & March), Greeshma (Summer:- April & May), Varsha (Rains:- June & July) Sarath (Autumn:- August & September), Hemanta (Pre-Winter:- October & November) and Sishira (Winter:- December & January). The English months given are approximations. Seasons change widely in northern and southern India. Besides these seasons shift their temporal location in course of several centuries.
The Precessional Motion and the Shift of Seasons
Ancient Indian Astronomers including Vedic seers and Valakhilyas were keen observers of the motion of sun and were keepers of centuries long tradition of watching the movement of sun across the background of fixed stars and stellar constellations in the sky of Earth. They observe the position of Sun during Winter Solstice, Vernal Equinox, Autumnal Equinox and Summer Solstice in the background of the constellations observed in the sky. In a period of one or two years no change is noticeable. But in the course of a century, changes are noticeable. Due to the precessional motion (rotation of Earth's axis) the position of sun at Winter Solstice shift with respect to the stellar background by 1 degree in 71.6 years (length of the life of an average healthy human being). It traverses 30 degree or one zodiac-sign in 2148 years. It completes 360 degrees of one full circle of the zodiac in 25,776 years. This 25,776 years is figuratively called the Great Year, the Divine Year and One Year of the Devas.
Similarly all other points (Vernal Equinox, Summer Solstice and Autumnal Equinox) that constitute the "four corners of the sky" too shift following the Winter Solstice. Along with the four crucial points of the sky, all the six seasons too are shifted.
The shift progress in the anti-clockwise direction, ie instead of moving from Aries to Taurus to Gemini, they move from Aries to Pisces to Aquarius.
Calenders are systems of time framework that help us to know what day of month it is and what month of an year it is. Calenders also count years from the year of start of the calender system. Examples of Calender systems are Shaka Calender established in 78 CE, Kolla Varsham Calender established (or rather re-established) in 825 CE, the Julian Calender established in 45 BCE and many more.
A 1 degree shift of Winter Solstice does not cause any disturbance in the calender system. But in a period of 2148 years (ie in around two millennia) the shift will be around 30 degrees, which is equivalent to one constellation in the sky and one month of an year. This is substantial change which makes all existing calenders useless. For example if one do not make any change in the existing calenders in 2148 years we will see that seasons are shifted by a month. For example, 2148 years in the past, ie in 136 BCE, Vernal Equinox occurred in April 21st instead of March 21st. Then spring started in January rather than in February.
Often calenders are designed such that Vernal Equinox is close to the beginning of the first month / first zodiacal sign. After 2148 years this no longer will be true, causing the astronomers to redesign their calenders. Some calenders adjust themselves to shift of equinoxes and solstices by changing the first month of the year. Some other calenders are discontinued and new calenders are adopted. Often the new-year date of discarded or destroyed calender is still remembered as a celebration. In some cases the practices followed in old calender continues to be part of some traditions though not attached to the active calender system.
A Calender with Pisces as the first month / sign
As an example of self-adjusting calender we have the astrological calender followed in Kerala, the southern state of India. In this calender the astrological year starts with Pisces (Meena) rather than with Aries (Mesha / Meda). Currently the Vernal Equinox is at the beginning of Pisces, ready to enter Aquarius. So it make sense to consider Pisces as the first zodiac sign or the first month.
A Calender with Leo as the first month
The Kolla Varsham calender in Kerala consider Leo (Simha / Chingam) as the first month of the year. Vernal Equinox was at the beginning of Leo, ready to enter into Cancer in around 8728 BCE. Thus this calender in Kerala is a remnant of an old calender that started in 8728 BCE when this region was ruled by a king named Mahabali. The first day of Chingam is considered as a New Year and the day when Moon in this month comes close to the star Sravana is celebrated as Onam a great festival associated with king Mahabali's return from his exile in Patala (South America).
Calenders with Aries as the first month / sign
Another New Year in Kerala is celebrated based on another calender in the month of Aries (Mesha / Meda) named Vishu or Vaishakhi. The date of this New Year usually falls in April 14, 15 or 16. It is now celebrated as an ancient Vernal Equinox. A Vernal Equinox in April 15 means it occurred 25 days later than March 21st (current date of Vernal Equinox). Since 365.25 days of the year corresponds to 360 degrees of the zodiac, 25 days corresponds to 24.64 degrees. One degree shift requires 71.6 years, so 24.64 degrees shift requires 1764.27 years. So Vernal Equinox was at April 15th 1764.27 years ago, ie in 247 CE. During this time Vernal Equinox point was still in Pisces but very close to the beginning of Aries. Hence the builders of calender in those days chose Aries as the first month and first zodiac sign. Arrival of calender start dates based on Gregorian calendar is not absolutely accurate because of errors in Gregorian - Julian calender and because of the Luni-Solar nature of the Vishu Calender due to which New Year day (Vishu) varies as April 14, 15 and 16.
As per Julian calender one year is 365.25 days. Gregorian calender corrected it as 365.2425. But Ancient Indian calenders were based on more accurate calculations which consider an year to be 365.2421756 days (only 1.4 seconds shorter than the modern scientific value of 365.2421904 days. See:- maya-s-theory-of-sun).
Western Astrology Calender
In some cases, the practices followed in old calender continues to be part of some traditions though not attached to the active calender system. For example in Western Astrology, Aries is considered as the first sign. Vernal Equinox was at the beginning of Aries ready to enter Pisces in around 136 BCE. This period was also the beginning of modern western astrology. There is a huge debate going on if the predictions based on western astrology needs to be shifted by a month. In my opinion, this depend on whether western astrologers want to base their predictions on the fixed zodiac or on the equinoxes and solstices which keep on moving around 1 degree every 72 years.
Much like the division of sky into 12 zodiac signs, the Nakshatra system is a unique division of sky into 27 parts using 27 easily identifiable stars in the zodiac, ie in the path of Sun, Moon and the planets. Some astronomers identify 26 and some others 28 such stars and hence the division of zodiac based on Nakshatra-system may vary from 26 to 30. In case of 26 Nakshatras, crossing of one Nakshatra region by Vernal Equinox will require close to a millennium (991.3846 years). In case of 27 Nakshatras, one division will span 13.3333 degrees (ie exactly 13 degrees and 1/3 degrees more, a more manageable fraction). When 30 Nakshatras are used one division will span exactly 12 degrees. The most popular Nakshatra system uses 27 Nakshatas. The system which provide ease of observation and which deals with more manageable fractions is preferred.
Kaalachakra with Yuga Chakra Inside. A refined Markandeya Yuga Chakra with Ascending and Descending Chaturyugas each with a duration of 12888 years is depicted. Negative Numbers are BCE years and Positive numbers are CE Years.
The Yuga System existed side by side with Nakshatra System (with its 27 divisions of zodiac) and with the Kalachakra system (with its 12 divisions of zodiac). But it has more to do with historical or geological epochs and less with astronomical observations. However the historical events expressed as having occurred in a particular Yuga may be fixed in time axis using astronomical observations. There are some indirect correlations with Yuga System and with Kalachakra (12 spoked wheel of time or zodiac).
Ascending and Descending Chatur Yugas
It has mainly four divisions called Rta Yuga, Treta Yuga, Dwapara Yuga and Kali Yuga. The divisions can be of equal size (1:1:1:1) or follow a ratio (4:3:2:1). The four Yugas together is called a Chatur-Yuga. In some definitions there are both ascending and descending Chatur Yugas. An Ascending Chaturyuga is defined starting with Kali Yuga, then Dwapara, Treta and Rta Yugas. After this the Descending Chaturyuga proceeds as Rta, Treta, Dwapara and Kali Yugas.
Duration of a Chatur Yuga
The duration of a Chatur Yuga varies based on the definition as 10,000 years (Sanjaya's Definition), 12,000 years (Markandeya's Definition) or 4,320,000 years (Shanti Parva Definition). Of this the 12,000 years Yuga defined by Markandeya is the one that aligns closely with the 25,776 year long axial precession if ascending and descending Chaturygas are taken together (a total of 24,000 years). Markandeya system also has the concept of dawn and eve. These are periods with 1/12th of the size of Yuga duration at the beginning and end of each Yuga were the effects of the adjacent Yuga too is felt. For example, the dawn and eve of Kali Yuga having 1200 years duration is 100 years each and that of Dvapara Yuga of 2400 years duration is 200 years each.
Reason for the 4.32 million long Chatur Yuga
In 4,320,000 year long Chatur Yuga definition 12,000 year long Markandeya Yuga duration is multiplied by 360 saying 360 human years constitute one year of the Devas. Actually what is meant here is that 360 degree motion of Vernal Equinox (ie one revolution of Vernal Equinox or one complete turn of axis of rotation due to precession) in 25,776 years constitute one Great Year, which can be figuratively described as One Divine Year or One Year of the Devas. But this does not require any multiplication of 12,000 years with 360. This error in the Shanti Parva of Mahabharata is copied into all Puranas including Vishnu Purana and Bhaagavata Purana. Currently many Hindus believe in this 4,320,000 year long Chatur Yuga in which current Yuga viz. Kali Yuga is thus unnecessarily and erroneously long (432,000 years long).
Refined Markandeya Yuga System
Markandeya Yuga system itself seems to be an approximation of the actual Chatur Yuga definition which was half the size of axial precession period (ie 12,888 years) so that ascending and descending Chatur Yuga will constitute one complete precession in 25,776 years. Such approximations are rampant in ancient Indian scriptures to facilitate easy memorization. For example the number 71.6 (the number of years taken for the Vernal Equinox to traverse 1 degree in its circular motion) is often approximated as 72 and is found in Vedic hymns.
A refined Markandeya Yuga Chakra with Ascending and Descending Chaturyugas each with a duration of 12888 years is depicted. Dawn and Eve of each Yuga is marked. Negative Numbers are BCE years and Positive numbers are CE Years.
Historical and Geological events in Yugas
The beginning and end of each Yuga is marked by an event especially the death or birth of a historical figure. The Descending Treta Yuga is marked by the death of Rama and the Descending Dwapara Yuga is marked by the death of Krishna. Birth of a king named Avikshit is mentioned as the beginning of Descending Treta Yuga. At the beginning and end of Descending Rta Yuga there were floods. There were floods in the beginning of the Descending Treta Yuga. Sarayu river that flows through Rama's city Ayodhya, was flooded during the end of Descending Treta Yuga. Dvaraka, the island city of Krishna was submerged due to flooding of sea water at the end of Descending Dwapara Yuga.
Saptarshi, the Seven Sages
Saptarshi is the name of a constellation near celestial pole and also the collective name of the seven sages who carries forward the secret of Kalachakra. This constellation also plays a role in the movement of the wheel of time as some of the stars in it becomes the pole-star due to the precessional movement. It is known as Big Dipper and Ursa Major (Great Bear) in western astronomy. The names of the seven sages differ based on the source text. Popular list include Bhrigu, Atri, Angirasa, Marichi, Pulastya, Pulalaha and Kratu. Sometimes Marichi is replaced by Vasistha and either Atri or Kratu replaced by Agastya.