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
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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
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
Vishu Calender
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.
Nakshatra System
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.
Yuga System
See More discussions on Yuga System in this series of articles:- Yugas
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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.
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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.
http://ancientvoice.wikidot.com/article:kalachakra