The Sun often appears white because of its intrinsic brightness and the way its light is scattered when it passes through Earth’s atmosphere. Here are some factors that contribute to this perception:

1. Wavelengths and Appearance: The Sun emits light across a broad spectrum of wavelengths, which includes visible light. The color of the Sun appears white or sometimes even slightly yellowish when it’s not obscured by particles in the atmosphere, such as during clear daylight. The human eye perceives a combination of all the wavelengths of light the Sun emits as white.
2. Scattering of Light: During sunrise or sunset, the Sun is near the horizon and its light must pass through a larger portion of Earth’s atmosphere than when it’s directly overhead. The Earth’s atmosphere scatters shorter blue and green wavelengths of light more than the longer red and orange wavelengths. As a result, the light that reaches our eyes during these times is dominated by the longer wavelengths, giving the Sun a reddish or orange appearance. However, when the Sun is high in the sky, the light that reaches us has passed through less atmosphere, and the scattering is less pronounced, allowing a broader range of wavelengths to reach us, thus making it appear white.
3. Atmospheric Conditions: The amount of scattering also depends on the amount of dust, water vapor, and other particles in the atmosphere. If the atmosphere is particularly clear, the Sun might appear brighter and more white. Conversely, on hazy or smoky days, the scattering can be more significant, and the Sun might appear more yellow or even orange.
4. Perception: Our eyes and brains interpret the light we see, and the perception of color can be influenced by surrounding light conditions. For example, if the sky is very blue due to scattered sunlight, the Sun might appear more yellow or white by comparison.
5. Sunspots and Solar Activity: Sometimes, the Sun’s surface is marked by dark sunspots, which can affect our perception of its color. When there are many sunspots visible, they can make the Sun appear darker overall, making the white appearance of the Sun more pronounced when sunspots are not visible.

In reality, the Sun is mostly a yellow-white star, but its appearance can vary depending on the conditions under which it is observed.It’s important to note that staring directly at the sun can cause serious and permanent eye damage, regardless of whether it appears white or yellow. Therefore, never look directly at the sun without proper protective eyewear.