Western astrology begins the year on March 21 at the spring equinox, the day the Sun enters Aries. Most of us don’t give much thought to Earth’s wobble, but it does wobble — slowly and consistently — as it spins around its axis. This means the spring equinox will eventually appear in other signs of the zodiac. This is called the precession of the equinoxes.

One complete rotation around the zodiac takes just under 26,000 years. So it takes Earth almost 2,160 years to travel through one zodiacal sign. The movement flows from the last sign to the first, from Pisces to Aquarius, and so on. Each of these is called an astrological age. Each era, lasting about 2,160 years, carries the characteristics of the zodiac sign present at the time of the spring equinox.

Currently, the spring equinox falls near the beginning of Pisces. And because it is moving backward, we are approaching the end of the Age of Pisces. When the spring equinox moves into Aquarius, we will move into that sign and reflect its characteristics for the entire age.