Retrograde
An apparent reversal in a planet’s motion against the stars.
The physical explanation
Retrograde motion comes from a changing viewpoint as Earth and the other planets orbit the Sun. For outer planets such as Mars, Earth overtakes them. Inner planets such as Mercury move faster and pass between Earth and the Sun during their retrograde cycle. Neither reverses its orbit. Our separate Mars teaching model uses circular orbits in one plane; the Time Machine uses calculated positions on real dates.
Explore real dates in the Time Machine ↗Try the simplified Mars teaching model ↗The traditional association
Some modern Western astrologers read retrograde motion as a prompt to revisit how a planet’s symbolism is expressed. This is a symbolic reading, not a physical effect or a prediction of an inevitable event.
Reference: NASA · Mars in the Loop (physical explanation) ↗
Editorially reviewed 2026-10-24 · prepared 2026-10-24.