Why did ancient people worship sun?

Answer: Sun essential for survival

Didn't understand astronomy yet — Wrong. Ancient people didn't understand nuclear fusion, but they clearly understood the sun's importance: it provided warmth, light, and made crops grow. Sun worship reflected this recognized dependence, not just ignorance.

Sun essential for survival ✓ — Correct! The sun was obviously important to survival: it warmed the Earth, provided light, and made crops grow. Agricultural societies depended on predictable seasons and sunshine. Sun worship (Egypt's Ra, Aztec's Tonatiuh, etc.) reflected recognition of this dependence. Solar eclipses terrified people because the sun's disappearance threatened existence.

Priests invented sun worship — Wrong. Sun worship emerged naturally across many cultures independently because the sun's importance to agriculture and survival was obvious. Priests organized worship, but the veneration arose from real dependence on sunlight for crops, warmth, and life.