Why do planets appear to wander?
Show answer & explanation
Answer: Relative motion creates patterns
Relative motion creates patterns ✓ — Correct! Ancient Greeks called them 'wanderers' (planetes). From Earth, planets usually move eastward against stars (prograde). But when Earth passes slower outer planets (or faster inner ones pass us), they appear to move backward (retrograde). It's like passing a slower car—it seems to move backward! Copernicus' heliocentric model explained this perfectly!
Magnetic fields push them — Wrong. Magnetic fields don't affect planetary motion. Retrograde motion is an optical illusion from Earth's faster orbit passing slower outer planets.
Earth's wobble causes movement — Wrong. Earth's axial precession is too slow. Retrograde motion happens because Earth and planets orbit at different speeds—creating apparent backward loops.
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