Why are sunsets red?

Sunsets look red because evening sunlight reaches you after crossing a much thicker stretch of air. Tiny gas molecules and dust scatter shorter blue and green waves away first, so the colors that keep traveling toward your eyes are mostly red, orange, and pink.

The lovely bit is that the sun has not changed at all. Your family is seeing Earth’s air act like a sorter, letting longer red wavelengths through after the bluer light has been sent in other directions across the sky.