The all-powerful being in our atmosphere is the sun. It is the centre of our system and very much its boss also. Some describe its color as orange, some say red and some even yellow. Everyone can come up with endless, logical and sometimes illogical examples to support the colour which they think the sun is. But, sadly, none of them are right.
It is important to understand how objects get their colour and characteristics of light, if one wants to find the exact colour of the sun. Non-luminous objects, which do not emit any kind of light, get their colour from the light they reflect from white light. As white colour consists of seven colours when it falls on a certain object, the object absorbs few colours and then reflects the remaining
and that complimentary colour reaches our eyes and we perceive it as the colour of the object.
On the other hand, self-luminous objects, like stars and sun, are of the colour they emit. If the object emits red light it appears red, if it emits yellow light it appears yellow, like the colour bulbs we see in our day to day life. So to know the colour of sun we need to understand the radiations it emits (radiation is another term for light). Different radiations have different wavelengths(λ), the colour blue(~350nm) has the least wavelength, while the colour red(~650nm) has the longest wavelength out of all the visible colours(350nm-650nm). For stars, radiations they emit depending on their temperature and they usually emit a higher range of radiations.
The above formula gives us the relation between the wavelength of radiation emitted and temperature of a star. The temperature of sun ranges from 6000K to 5000K (0°C = 274 Kelvin) and the wavelength of light emitted comes out to be 350nm-750nm. With the values of wavelengths obtained one can easily understand that sun emits all colours in roughly equal proportions and so the light emitted by sun is a mixture of all the colours, which collectively become white. Yes, the actual colour of the sun is white and that is the colour visible moon. It is important to remember that apart from visible radiations, the sun also emits invisible UV and infrared radiations but they can be ignored because they do not contribute to the colour of the sun.
Usually, we see the sun as red or yellow in colour. However, it actually depends on the amount of scattering the blue colour faces, that ultimately affects the colour we perceive.This colour change happens because of the phenomenon called Scattering of light, which simply means that the light is forced to change its path because it comes into contact with atmospheric particles. Scattering is inversely proportional to four times the wavelength of light. So the lesser the wavelength, the more the scattering of colour occurs and vice versa.
In the afternoons, the blue light faces lesser resistance, resulting in us viewing the light as yellow in colour. In evenings, sunlight has to pass through many layers of atmosphere thus, the colour blue is scattered more and the colour red dominates, therefore, the rays of the light that reach our eye.
The different colourful photos of sun released by international space organizations also create misconceptions about the colour of the sun. The photos show the sun in different colours because of the filters they use. They take photos of sun with different filters to understand the structure and chemical composition of sun. It is the time we understand that our everything we see should not be accepted blindly and we need to be curious enough to further follow up on what we read. We at Gyanopedia strive to do so.