People often ask why the sky is blue; this answer lies within atmospheric gases and dust particles which scatter sunlight back onto Earth, with blue wavelengths being scattered more often than any other hues.
Tamil language provides distinct words for blue (neela – niil), green (pcc paccai) and yellow. Furthermore, light sky blue can also be described.
Light
On a typical day, sunlight passing through Earth’s atmosphere gets scattered and dispersed into different directions by various wavelengths – especially those sensitive to our eyes such as blue and violet wavelengths that our eyes respond most strongly to. Due to this dispersal process, blue wavelengths become concentrated more than other wavelengths in the sky causing it to appear bluer than it really is while some wavelengths pass straight through without absorption and give an impression that the sky is white.
As the sun sets and rises, its effects on the sky shift from deep blue to red as more sunlight travels through atmosphere and more blue light is scattered, leading to redder wavelengths being redirected back into our view. Furthermore, pollution, dust, and aerosols in the atmosphere cause even further scattering of blue wavelengths that further reddens them.
Tamil language represents blue as “neela”, with different shades from light cyan to deep teal being classified under this umbrella term. Blue is one of the most prevalent colors found in nature and often associated with peace, harmony, and intellect.
Tamil has two words for representing green: pcc pacca and manja pcc pacca respectively, with additional terms used for specific shades such as light green (pcc kootu) or bright yellow (psupupcc akootu).
Blue, or “neela or nila”, in Tamil is one of three primary colors derived from Sanskrit nava-dhatu and forms one of three primary hues along with red and yellow. Blue dominates sky, water and sea environments due to the Rayleigh effect absorbing most infrared radiation from the Sun leaving mostly visible rays containing predominantly blue-violet hues from its sunbeams; similar phenomena also take place on other planets but with differing atmospheric compositions; hence most skies appear blue due to similar processes than found here on Earth despite not all having blue atmospheres like our own!
Atmosphere
The blue hue of the sky comes from gases and particles in Earth’s atmosphere. When sunlight passes through this layer, it is scattered by these particles and gases and causes certain wavelengths to be more prominent, giving the sky its distinctive blue color.
The atmosphere can also alter the look of both the sun and moon. At low horizon levels, sunlight has had more time to travel through its journey through atmosphere; at higher heights however, less chance of scattering occurs as less energy from its journey has reached earth.
As with clouds and water, the atmosphere also plays an important role in their color. When raining occurs, moisture in the atmosphere causes clouds to turn gray while when there is no rainfall present will make them whiter in hue. Thus making weather changes so abrupt.
Rayleigh scattering explains Earth’s blue sky. As light enters our atmosphere, its wavelengths disperse into various hues with shorter wavelengths being scattered more easily than longer ones like red or green; blue wavelengths thus tend to dominate and give off their characteristic hue of sky-blue color.
Some languages use separate words for blue and green; classical Arabic uses zraq for blue while akhdar refers to green; in Hindi these terms correspond respectively, with blue being called nyl (niila) and green being sbz (sabuj). Finally, Chile and Argentina’s Mapudungun language distinguishing blue from green with words such as kuru/payne.
Other languages also use single words for blue and green to differentiate them, including Zulu and Xhosa languages. Speakers of these mutually intelligible dialects can add descriptive adjectives after their color term to further distinguish it from similar shades – for instance (lu)hlaza okwesibhakabhaka is often translated to mean ‘like the sky’ while (lu)hlaza okwotshani means ‘like grass’.
Clouds
Sky blue hue is caused by clouds. When sunlight enters our atmosphere and is scattered by air molecules, shorter wavelengths (blue) tend to be scattered more than longer wavelengths (red). This gives an illusion that the Sun is closer than it actually is and causes its image to appear within our skies – creating the look of blue.
At night, the sky is dark with stars visible unless obscured by clouds. Additionally, Moon and planets may also be visible if not obscured by clouds; their visibility due to reflecting sunlight may make the Moon appear white while planets display different hues as their reflection varies based on where each planet was reflecting from other stars.
Sky color depends on atmospheric composition; however, the Sun remains constant. Dawn and dusk often bring different hues due to more atmospheric layers being penetrated during sunrise and sunset; more blue light travels through these times due to scattering by particles in the atmosphere, thus leaving more red and yellow wavelengths for us to enjoy.
On Earth, skies of various hues are commonplace; other planets with differing atmospheric compositions could have colored skies instead. Some planets feature thick atmospheres that obscure sunlight while others allow more sunbeams through.
Other languages use words for shades of blue such as azure, indigo and sky blue to refer to different shades. Italian uses two terms; azzurro refers to cloudless skies while celeste refers to darker tones of the hue.
Arabic dialects typically use the words sibi for blue and khadra’ or al-khadra’ for green. Classical Arabic poetry by al-Zawahiri utilizes the terms zraq’ or khdar’ to refer to the colour of the sky.
The Sun
A blue sky is created when sunlight reflects off lakes and oceans, as the water molecules in these bodies absorb long wavelengths such as red and orange light from sunlight, while shorter wavelengths get scattered back by atmospheric processes – this phenomenon is called Rayleigh scattering and it gives our sky its distinctive hue.
At sunrise and sunset, this same phenomenon accounts for its blue hue. At these times, when traveling through more atmosphere than when high in the sky, more wavelengths of light reflect back onto us allowing more reds and yellows through to our eyes directly.
Unsurprisingly, the color of the sky varies across planets. Mars for instance has a very thin atmosphere similar to that of the Moon; as a result, sunlight must travel a very long way before becoming scattered; hence why sunset and sunrise appear blue instead of red on Mars!
Many languages have various terms for the different shades of blue, such as French’s bleu clair (“light blue”), bleu ciel (“sky blue”), bleu marine (“Navy blue”), and bleu roi (“royal blue”). Chile and Argentina’s Mapudungun language distinguishes between black (kuru) and payne – two shades of blue that differ greatly in tone and hue respectively.
Another fascinating language, Zulu has only three other color words to differentiate shades of blue and green; speakers of this tongue can identify these shades by adding descriptive terms: -luhlaza okwesibhakabhaka (“like the sky”) or -luhlaza okwotshani (“like grass”).