Sun's ray → subsolar point
Tropic of Cancer (+23.4°)
Equator (0°)
Tropic of Capricorn (−23.4°)
Polar circles (±66.6°)
The Sun stays fixed; the tilted Earth spins as you scrub time. Watch the bright spot ride up to Cancer in June, down to Capricorn in December, and cross the Equator at the equinoxes.