Many people perceive the Sun as being yellow, orange, or red, largely due to the common images and illustrations portrayed in various media and from everyday observations during sunrise and sunset. However, scientifically, the Sun is not restricted to these hues. It is, in fact, essentially a mixture of all colors combined, which blends to produce what we see as white light.
The misunderstanding arises from the way light interacts with Earth's atmosphere. When sunlight enters the atmosphere, it scatters in all directions, predominantly scattering colors with shorter wavelengths, particularly blue and violet, more than those with longer wavelengths like red, yellow, and orange. This phenomenon, known as Rayleigh scattering, is why the sky appears blue during the day. At sunrise and sunset, the Sun's light has to pass through a thicker slice of Earth's atmosphere. More blue and violet light is scattered out of the direct path between the Sun and our eyes, allowing reds and oranges to dominate the visual spectrum we see, thus the Sun appears more orangish or reddish during these times.
However, if viewed from space or high altitude without the interference of the atmosphere, the Sun would appear as it truly is: a bright white star. Its white appearance is due to the fact that it emits an almost equal amount of energy across most wavelengths of the visible spectrum. The Sun's surface temperature is a crucial factor in determining its color. The surface temperatures of stars dictate their color, from the cooler red stars to the hotter blue stars. Our Sun, with a surface temperature of about 5,500 degrees Celsius, emits light strongly across the full spectrum of visible colors, though with a tiny peak in the green.
In essence, the Sun can be thought of as a natural white light source. The color changes we perceive from Earth are merely due to atmospheric effects and not due to the actual inherent color of the Sun. This shows not only the complexity of astrophysical phenomena but also how our own environment plays a crucial role in the way we perceive the world around us. Thus, the pale yellow to white color of the Sun we see midday, when the sun is high and the atmosphere scatters less of the shorter wavelength colors, is actually a truer representation of the Sun's visible spectrum than the dramatic hues of dawn and dusk.
