The Sun is Not Actually Yellow

The Sun is white. We only perceive it as yellow or orange because the Earth’s atmosphere scatters shorter wavelengths of light, such as blue and violet, leaving the warmer colors to reach our eyes.

In space, there is no atmosphere to scatter the light. Because the Sun emits all colors of the visible spectrum at roughly the same intensity, our eyes perceive the combined result as a brilliant, stark white. If you were to look at it from the moon, there would be no hint of gold or lemon.

This phenomenon, known as Rayleigh scattering, is the same reason the sky looks blue during the day and red at sunset. When the Sun is low on the horizon, the light has to travel through more of the atmosphere, filtering out even more color until only the longest wavelengths—reds and oranges—remain.

Astronomers technically classify the Sun as a 'G-type main-sequence star,' or a 'yellow dwarf.' This name is a legacy of how we see it from the ground and its temperature profile, but it is fundamentally misleading. If the Sun were truly yellow, white objects on Earth would appear yellow in the midday sun.

Even more surprising is that if you measured the light by its most intense wavelength, the Sun would technically peak in the green part of the spectrum, yet we never see a green star because of how our brains process color mixing.