We
find Yuga cylces
mentioned not only in astronomical works, but also in mythological works in
India.
Kali Yuga began
on the midnight of 17th Feb 3102 BCE and the duration of this Kali Yuga is
said to be 4.32 K solar years. Dwapara is
2*Kali Yuga years. Treta is
3*K Y and Krita
Yuga is 4*K Y.
Krita Treta Dwaparascha Kalischaiva Chaturyugam
Divya Dwadasabhir varshai savadhanam niroopitham
Thus an Equinoctial Cycle, Mahayuga is
equal to 4+3+2+1 = 10 KYs.
E C = 10 KYs.
A Greater Equinoctial Cycle ( Manvantara )
= 71 Equinoctial Cycles
There are cusps happening in between Manvantaras, each
equal to a Krita
Yuga in duration. A
Krita is equal to 4 KYs or 2/5 of a Maha Yuga. Since there will 15 such cusps
happening amongst the Fourteen Manvantaras, they are equal to 15*2/5 = 6
Mahayugas.
Hence 14*71+6 = 1000 Mahayugas =
4.32 Billion Years
Sahasra yuga paryantham
Aharyal brahmano vidu
Ratrim yugah sahasrantham
The Ahoratra vido janah ( The Holy Geetha ).
This is one Cosmological Cycle, called Brahma
Kalpa.
Chaturyuga sahasram indra harina dinam
uchyathe
From one second, it can be logarithmically shown, upto 10^22 seconds. This is
what the above diagram shows. This diagram is by courtesy of Wikipedia.
From 10^0 it goes upto 10^22 seconds. One day of Brahma is
4.32 billion years and 100 years of Brahma therefore
is 311.04 trillion years, which is shown logarithmically above.
One Asu is
4 seconds, one Vinadi is 24 seconds and one Nadi is 24 minutes. 60 such Nadis
make up one day. This is the Sexagesimal division of a day into 60 Nadis ! In
Astronomy, one degree is sixty minutes and one minute is sixty seconds. Hence
sexagesimal division is justified ! 365.25 such days constitute a year and
Hindu calculation goes upto 311.04 trillion years !
Mean
and true planetary longitudes in the Zodiac is computed by Nine Orbital
Elements, in Indian Astronomy.
Mean longitude of Planet, Graha
Madhyama , M
Daily Motion of the Mean Longitude, Madhyama
Dina Gathi, Md
Aphelion, Mandoccha,
Ap
Daily Motion of Aphelion, Mandoccha
Dina Gathi, Apd
Ascending Node, Patha,
N
Daily Motion of Ascending Node, Patha
Dina Gathi, Nd
Heliocentric Distance, Manda
Karna, radius vector, mndk
Maximum Latitude, L, Parama
Vikshepa
Eccentricity, Chyuthi,e
In Western Astronomy, we have six orbital elements
Mean Anomaly, m
Argument of Perihelion, w
Eccentricity, e
Ascending Node, N
Inclination, i, inclinent of orbit
Semi Major Axis, a
With the Nine Orbital Elements, true geocentric longitude of the planet is
computed, using multi step algorithms.
There is geometrical equivalence between both the Epicycle and the Eccentric
Models.
The radius of the Epicycle, r = e, the distance of the Equant from the
Observer.