The Sun doesn’t actually emit only yellow light. It emits light across a broad spectrum of wavelengths, including all colors visible to the human eye. The Sun’s spectrum peaks in the green wavelength, surprisingly. So, why doesn’t it look green?
The Sun emits a nearly equal amount of light across the visible spectrum. Human eyes don’t perceive color by averaging the wavelengths. Instead of seeing green, we perceive this balanced mix of colors as white. For the Sun to appear green, it would need to emit predominantly green light.
So why does the Sun often appear yellow? This is due to the Earth’s atmosphere. Our atmosphere scatters blue light more effectively than red light. This phenomenon, known as Rayleigh scattering, is why the sky appears blue. The removal of blue light from the Sun’s white light leaves a yellowish hue.
The effect is amplified at sunrise and sunset. As the Sun’s light travels through a thicker layer of atmosphere at these times, more blue light is scattered, resulting in even redder hues. This explains the vibrant oranges and reds we see during these times of day.
Therefore, while the Sun is essentially white, atmospheric scattering causes it to appear yellow to our eyes. The amount of yellowness can vary depending on the time of day and the amount of atmosphere the sunlight passes through.
