A Yuga In Hindu philosophy is the name of an 'epoch' or 'era' within a cycle of four ages.According to Hindu cosmology, life in the universe is created, destroyed once every 4.1 to 8.2 billion years, which is one full day  (day and night) for    Brahma. The lifetime of     a Brahma himself may     be 311 trillion and 40       billion years.The cycles are said to repeat like the seasons, waxing and waning within a greater time-cycle of the creation and destruction of the universe. Like Summer, Spring, Winter and Autumn, each yuga involves stages or gradual changes which the earth and the consciousness of mankind goes through as a whole. A complete yuga cycle from a high Golden Age of enlightenment to a Dark Age and back again is said to be caused by the solar system's motion around another star.
So if we were to reflect on our humanities history it simply wouldn't make sense to think of it in terms of a linear evolution. I don't think we could have possibly gone from unintelligent apes to a complex society that destroys its own habitat. I don't consider where humanity is at today as the most evolved we can be as a species, I believe that humanity has had its ups and downs over this 26,000 year cycle.
Now for the Procession of the Equinox let's first start with the word Procession.  Precession is a change in the orientation of the rotational axis of a rotating body. An Equinox is when the Earth's axis is inclined neither away from nor towards the Sun, the center of the Sun being in the same plane as the Earth's equator. It can also be when the date of which day and night are equal. So in simpler terms the earth has a wobble.

​So with this we can now talk about the effect the earth has when its northern point is facing toward the center of the milky way galaxy and when it is pointed away from the center of the galaxy. Now the center of the galaxy may be a lot of energy and light but it also contains a large amount of universal consciousness. So this would most definitely explain how during the turning away from the center of the galaxy, humanity has gone through a sleeping period and now is just beginning to wake up. This would actually explain how civilizations like the Egyptians and the Sumerians had such amazing complex structures with the intention of raising the consciousness of our planet. For example the Great pyramids being conductors of energy. This is done by the pyramidal structure being a great conductor of energy combined with the limestone it is made out of on top of it being right over a body of water which would conduct that energy​.    
The Procession of the Equinox goes through one full rotation in a span of around 26,000 years. Many indigenous cultures know of this spectacular event and have watched it occur over these long periods. The Mayans actually set their ancient calendar for a new age on December 21, 2012 based off the knowledge they had from the Procession of the Equinox.
The 21st marked off the new age of Aquarius. The aquarius symbol represents 'closure in water '. Water represents the collective unconsciousness of the planet and many believe the age of Aquarius will mean the return of the goddess, priestess, or feminine energies those that vibrate faster than physical frequency. This is the return to higher consciousness, the awakening of higher mind. The age of Aquarius is also know as "the age of freedom".