What Color Is The Sun?

  • The sun’s color is dependent on the sun’s surface temperature, Earth’s atmosphere, and the human eye
  • The sun’s light peaks in visible light around 500-nanometers, which translates to blue-green
  • Earth’s atmosphere causes the sun to appear yellow to our eyes

When we look at the sun, either with protective equipment or with solar observatories, it appears yellow to our eyes. The sun is often referred to as a yellow dwarf star, and so it seems obvious that the color of the sun is yellow. However, appearances can be deceiving. Although our eyes see the sun as yellow, that is not its true color. Rather, the color of the sun is dependent upon a number of factors, such as its surface temperature, Earth’s atmosphere, and how our eyes work. So what color is the sun?

Wavelengths Of Light

Solar spectrum
Spectrum of the sun's light

Color is simply the way our eyes perceive different wavelengths of light. Shorter wavelengths appear more blue, while longer wavelengths appear more red. Our eyes have evolved to see solely in the visible part of the electromagnetic spectrum, and that is due to the fact that the sun’s light peaks at those wavelengths. Although the sun emits light at every wavelength, its surface temperature causes the light it emits to have wavelengths that peak in visible light. By knowing the exact wavelength of the sun’s light, scientists can determine its true color. Interestingly, the sun’s light peaks around 500-nanometers, which translates to blue-green. Although our eyes see the sun as being yellow, its true color peaks in blue-green. 

Why Does The Sun Look Yellow?

Different wavelengths of light
The sun imaged in multiple wavelengths of light. Image credit: NASA/SDO

You may be wondering why the sun appears yellow if its true color is blue-green. This has to do with Earth’s atmosphere. When sunlight hits our atmosphere, shorter wavelength light is scattered. Scattered blue light is the reason why Earth’s sky is blue. Although most short wavelength light is filtered out by our atmosphere, longer wavelength light makes it through and reaches our eyes. When we account for our atmosphere, the sun’s light peaks in yellow, and that’s why we see it as yellow even though that is not its original color. 

What Color Is The Sun In Space?

The sun
The sun appears yellow-orange on Earth, yet looks white in space. Image credit: NASA/SDO

The sun appears yellow due to our atmosphere, so what color would the sun be in space? Do astronauts see it as blue-green or something else? Once you leave the Earth’s atmosphere, the sun appears white rather than any single color. This is due to how our eyes see color. Our eyes are unable to perceive a singular color of the sun because the amount of sunlight simply saturates the photoreceptor cells in our eyes, causing all the colors to be mushed together. When every color of light is combined, you end up with white. Thus, the sun appears yellow on Earth, white in space, and its true color is blue-green.