The remainder are colloidal particles, the atmosphere is filled with argon gas, the water either in the form of water vapor or ice crystals, and various solid particles such as dust, residual particles burning pollutants
and also salt especially for areas above sea level
The sun that enters the atmosphere meets the gas molecules and the dust particles. Color rays that have longer wavelengths such as red and yellow
can pass through and penetrate the molecules of gas and dust before But the blue color that has a shorter wave of light reflected back up. That's why the sky looks blue. The same principle applies also to water in the sea or lake that looks blue.
Previously the sun was white. The sun emits waves in all the visible spectrum of red, orange, yellow, indigo blue and other non-blue. Each color has different frequency and wavelength.....
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