Astronomy IV By Govind
Ahargana is defined as the no of days elapsed
after the start of the Iron Age, the Kali Yuga, which began on 3102 BC.
Kali Era = English Era +3102
The no of days elapsed from Kali Start was
1822903 on 13/04/1890.
Ahargana, d = ( xdate -
13/04/1890 ) + 1822903
where xdate is the date of birth.
This Ahargana is printed on every
Vedic Astrology Horoscope.
All calculations in Indian Astronomy are based on Ahargana. Ahas means day
in Sanskrit and gana means calculation.
The Kali Era, according
to the Hindu Calendar
The present Kali Era is therefore
3102 + 2014 = 5114
The difference between the Malayalam &
English eras are 825. Malayalam Era is 1185 now and if you add 825 to
Malayalam Era, you get English Era.
Malayalam Era + 825 = English Era
The Julian Calender used the value 365.25 d (
days ) for year and was proved erroneous. There were 10 days difference and
the Gregorian Calender, the present day Calender, came into being. Gregorian
uses 365.2425 d for year. The Gregorian is also not perfect, as the Tropical
Zodiac is moving, and may be subject to correction after some years. The
actual value of the year is
year = 365.256362424815 d
with twelve decimals. In my early days of progam
development, I used two decimals and there were many days of difference.
This value is given by Sir Simon Newcombe, according to Western Learning and
Aryabhata, according to Indian learning.
The great Jupiter - Saturn
In Indian Astronomy, the great Jupiter - Saturn
perturbation, is calculated using the formula given below.
The Kali year, ky, is calculated and 4660 is
deducted from it to get the kyb, the kali year balance. Its Bhujamsa,x is
calculated using the Equation of Bhuja and then its Bhujajya ( Sin x ) is
calculated to get the value of Manda Phala, a.
Mathematically, it can be written as
Y, (Year of Birth) + 3102 = ky, the Kali Year of
kyb ( kali year balance ) = ( ky - 4660 )
x = kyb*360/918
b, bhujajya = sin(x)
Since the duration is 918 years and perturbation
amplitude is 1187 seconds,
Manda Phala, a = sin(x) * 1187
( Example - My year of birth is 1955. Add 3102
and we get 5057. Less 4660 is 397. 397*360/918 is 155.6 and its Bhujamsa is
25 degrees roughly ( 180-155). So Sin (25 ) is 0.41. Manda Phala, therefore
is 0.41*1187 seconds or Vikalas. )
This value, Manda Phala, a is added to
Jupiterís mean longitude, if Joveís long is less than 180 and subtracted
if Joveís long is greater than 180.
In the West, this discovery is attributed to
Laplace. The duration of the perturbation of 918 years is known as Laplace
period. Its amplitude of .332 degrees is similar to the Indian value of 1187
Laplace gives the equation 2 nj - 5 ns +
constant, bringing to light the 5:2 Resonance in the orbits of the two
celestial giants. 2 revolutions of Saturn = 5 revolutions of Jupiter = 60