Why the sky is blue, the grass green, & the Sun yellow.: "Sky
The sky appears blue because as white light shines on Earth from the sun gas molecules in the Earth’s atmosphere absorb the “blue” part of the visible electromagnetic spectrum. [1] These molecules then radiate the blue light into the sky in a process known as the Rayleigh scattering. Our eyes see the scattered light and the sky appears blue. [2] Atmospheric gas molecules do not absorb other parts of the electromagnetic spectrum (red, yellow etc) to the same degree and we therefore rarely see those colors in the sky.
Grass
The grass appears green because plants contain a chemical called chlorophyll, essential to photosynthesis. Chlorophyll absorbs all parts of the visible spectrum of light except the wavelengths corresponding to the color green. Chlorophyll reflects the green light and as long as grass contains chlorophyll it will look green to us. [3]
Sun
The sun appears yellow because of the Rayleigh scattering: the light that eventually reaches our eyes from the sun on the surface of the Earth is predominately the “yellow” & “red” portions of the electromagnetic spectrum. In addition, the temperature of the surface of the sun happens to produce a spectrum of visible light where yellow is most plentiful (but if the Rayleigh sca"
