Why do astrologers use the “wrong” sign?
Precession of the equinox, caused by the cyclical change in the direction of the Earth's tilt, causes the position of the vernal equinox (the point where the path of the sun crosses the celestial equator) to move over time.  When the constellations were first described, the vernal equinox was in Aries, and so it is still called &quot;The First Point of Aries&quot;.  Now it is in Pisces and moving towards Aquarius. Astrologers use &quot;signs&quot; named according to the position of the vernal equinox when the constellations were first described.  So if a planet is at the vernal equinox (and therefore in Pisces, close to Aquarius) an Astrologer in the Western tradition will say that planet is &quot;in Aries&quot;.
So for an astrologer, &quot;Aries&quot; is not a pattern of stars in the sky nor the region of the sky surrounding those stars, but the strip in the sky between 0 and 30 degrees of longitude, even though that region no longer contains the stars of the constellation Aries.