The nakshatras are measured against the fixed stars, and Western signs against the equinox. Those two frames have drifted about twenty-four degrees apart, which is nearly a whole sign.

Earth's axis wobbles, so the equinox slides backwards through the stars at about 50 arcseconds a year. Indian astrology corrects for it with a figure called the ayanamsha — around 24°13' in 2026 on the standard Lahiri value — and Western astrology mostly does not. That is why the same Moon can be read as Taurus in one system and Aries in the other, and both can be self-consistent.