“Earth’s ~25,000-year precessional cycle; the ever changing relationship between the tropical and sidereal zodiacs… the Earth’s pole wobbles over a very long period of time (Nick Anthony Fiorenza, 2012).”
“Since the Earth’s rotational axis moves slowly in a circular precessional motion, the equinoctial point does not return to its exact starting place for 25,800 years. Instead, the vernal point moves in a retrograde manner through the zodiacal belt, increasing at a yearly precessional rate of 50.23 to 50.27 seconds per year.
“This varies slowly over time [this is due to being in a binary sun system, in which when we get closer to the other sun we speed up and when further away we slow down].
“Known as the Precession of the Equinoxes, this slow and steady backward movement of the vernal equinox along the ecliptic is behind the concept of planetary “ages”, as a new age is said to begin whenever the vernal equinox enters a new sign.
“It would take approximately 71.67 years for the equinoctial point to advance 60 minutes, or 1 degree (71.67 x x 50.23” = 3600 seconds, or 60 minutes, or 1 degree). If we multiply 71.67 (the time it takes for the equinox to advance 1 degree) by 30 degrees (one sign of the zodiac), the product is 2,150 years, the approximate time it takes for the vernal point to traverse an entire sign, this constituting the length of a planetary era.
“Since such calculations depend on the precise placement of the constellational boundary which demarcates 0° Aries, and on the rate of precession one uses, estimates among astrologers for the year when the Age of Aquarius actually begins range from at least 1787 to 2376.
“The Indian system of epochs (known as Yugas), which has nothing to do with these planetary ages is made up of four planetary eras which, when added together, comprise Maha Yuga (literally “great age”).
“Consisting of 4,320,000 years, Maha Yuga us divided into ratios of 4:3:2:1 as follows:
Krtia Yuga (Golden Age) = 4
Treta Yuga (Silver Age) = 3
Dvapara Yuga (Copper Age) = 2
Kali Yuga (Earthen Age) = 1
= 4,320,000 years² = 10
“The prevailing Kali Yuga began in 3102 B.C. when there was a grand conjunction of most of the planets. The number of years comprising Kali Yuga, 432,000 years-is equivalent to the number of years in the Great Babylonian Year, making it quite plausible that this information was brought over to India from the Near East (Dreyer, 1997).”
Nick Anthony Fiorenza/Lunar Planner. 2012. The Tropical and Sidereal Zodiaks & The Cycle of Earth’s Precessional Cross. [ONLINE] Available at: http://www.lunarplanner.com/siderealastrology.html. [Accessed 22 January 14].
Dreyer, R. G., 1997. Vedic astrology : a guide to the fundamentals of jyotish. 2nd ed. Boston, MA, USA: Red Wheel/Weiser.
^ book purchase from Amazon, Vedic Astrology: A Guide to the Fundamentals of Jyotish By Ronnie Gale Dreyer.