Rainbow

Science / Weather / Rainbow: A luminous arc featuring all colors of the visible light spectrum (red, orange, yellow, green, blue, indigo, and violet). It is created by refraction, total reflection, and the dispersion of light. It is visible when the sun is shining through air containing water spray or raindrops, which occurs during or immediately after a rain shower. The bow is always observed in the opposite side of the sky from the sun.
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Scattering

Science / Weather / Scattering: The process by which small particles suspended in the air diffuse a portion of the incident radiation in all directions. This is a primary reason for colors, such as blue skies, rainbows, and orange s MORE

Photometer

Entertainment / Photography / Photometer: Instrument for measuring light being reflected from a surface. It works by comparing the reflected light with a standard source produced within the photometer. MORE