Age of Aquarius

[4] The approximate 2,160 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 average can be computed by dividing the Earth's 25,800 year gyroscopic precession period by 12, the number of zodiacal signs.

Traditionally this 25,800 year-long cycle is calibrated, for the purposes of determining astrological ages, by the perceived location of the Sun in one of the 12 zodiac constellations at the vernal (Spring) equinox, which corresponds to the moment the Sun is perceived as crossing the celestial equator, marking the start of spring in the Northern Hemisphere each year.

The edge established between Pisces and Aquarius officially locates the beginning of the Aquarian Age around 2600 CE.

[6](p 263) They prefer the long-established convention of equally-sized signs, spaced every 30 degrees along the ecliptic, which are named after what were the 12 background zodiacal constellations when tropical astrology was codified c. 100 CE.

[11] Another view suggests that the rise of scientific rationalism, combined with the fall of religious influence, the increasing focus on human rights since the 1780s, the exponential growth of technology, plus the advent of flight and space travel, are evidence of the dawning of the age of Aquarius.

Rudolf Steiner had spoken about two great spiritual events: The return of Christ in the ethereal world (and not in a physical body), because people must develop their faculties until they can reach the ethereal world; and the incarnation of Ahriman, Zoroaster's "destructive spirit" that will try to block the development of humanity.

[13] In a 1890 article about feminism in the French newspaper La Fronde on 26 February 1890, August Vandekerkhove stated: "About March, 21st this year the cycle of Aquarius will start.

The song further defines this "dawning of the age" within the first lines: The 1969 cover version by American R&B group the 5th Dimension (a medley that also incorporates part of the song "Let the Sunshine In"), became a radio hit, remaining at number one on the US Billboard Hot 100 pop singles chart for several weeks.