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The approximate 2,150 years for each age corresponds to the average time it takes for the vernal equinox to move from one constellation of the zodiac into the next. This can be computed by dividing the earth's 25,800-year gyroscopic precession period by twelve, the number of zodiac constellations used by astrologers. According to different astrologers' calculations,
approximate dates for entering the Age of Aquarius range from 1447 CE (Terry MacKinnell) to 3597 (John Addey).[2]Astrologers do not agree on when the Aquarian age will start or even if it has already started.[3] Nicholas Campion in The Book of World Horoscopes lists various references from mainly astrological sources for the start of the Age of Aquarius. Based on Campion's research,
most published materials on the subject state that the Age of Aquarius arrived in the 20th century (29 claims), with the 24th century in second place with twelve claimants.[4]https://en.wikipedia.org/wiki/Age_of_Aquarius
