Earth wobbles. Very slowly, like a spinning top, its axis traces a circle over about 26,000 years. NASA calls it axial precession, and it’s real, measured astronomy.
Why it matters
Twice a year, around March 21 and September 22, day and night are about equal. Those are the equinoxes. Because of the wobble, the spring equinox drifts backward against the stars by about 50 arcseconds a year. That’s tiny, but over thousands of years it adds up.
That’s why there are really two zodiacs:
- The signs follow the seasons and start from the spring equinox each year.
- The constellations are the fixed star groups in the sky.
They used to line up, and they don’t anymore. Hindu astronomers tracked this by measuring from a fixed star, Revati, instead of from the equinox.
The older idea
This is where it turns from astronomy into belief.
In his 1894 book The Holy Science, Sri Yukteswar, the guru of Paramahansa Yogananda, tied this slow cycle to the great ages of human history. He described a 24,000-year cycle of four ages, with humanity’s awareness falling through one half and rising through the other. Tara Mata wrote about these world cycles in the 1930s.
Science doesn’t back that up. His 24,000 years doesn’t match the measured cycle of about 26,000, and the age-of-humanity part can’t be tested.
Why I still like it
The sky is moving on a clock far longer than any government, religion or empire. Whatever is happening right now, it’s a very small part of something very big. I find that calming.
The astronomy is fact. The ages are belief.