The Age of Aquarius is an Astrological Age derived from the Precession of the Equinoxes, when the Vernal Equinox (March) will have precessed into Aquarius. Currently we are considered to be in the Age of Pisces.

The Ecliptic is the apparent path of the Sun through the heavens, from Earth's viewpoint.

The Precession of the Equinoxes refers to the gradual backwards movement (counter-zodiacal) of the stars relative to Earth's seasons.

The Sidereal Zodiac measures the 12 zodiac signs relative to the fixed stars and constellations, rather than Earth's seasons.

The Tropical Zodiac measures the 12 zodiac signs relative to Earth's seasons, rather than the constellations of the same name.