What causes the seasons on Earth?

Earth's seasons come from the tilt of its axis, not its distance from the Sun. Each hemisphere takes turns leaning toward the Sun and getting more direct light. Earth is actually closest to the Sun in early January, during northern winter.

What's actually true

Seasons come from Earth's tilt, not its distance from the Sun. Many people assume summer happens when Earth is closest to the Sun. In fact, Earth's axis is tilted, so each hemisphere takes turns leaning toward the Sun and getting more direct light. The proof: Earth is nearest the Sun in early January, in the middle of northern winter.

Takeaway: Earth is closest to the Sun in early January, during northern winter.

Why people believe it

The distance explanation matches everyday experience: a fire feels warmer when you move closer, so summer should be when Earth is nearest the Sun. Diagrams drawn at an angle can make Earth's orbit look like a long, stretched oval, which makes the distance idea look even more convincing. The simplest check is that the two hemispheres have opposite seasons at the same moment, which distance alone cannot explain.

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