Natural Moment of Beauty and Grace over Woodbridge Island, Cape Town
Captured with Smartphone © Kenny Wilson, Arnhem, Milnerton
Published with permission from Kenny Wilson
What is a Rainbow?
"A rainbow is a meteorological phenomenon that is caused by reflection, refraction, and dispersion of light in water droplets resulting in a spectrum of light appearing in the sky. It takes the form of a multicolored circular arc. Rainbows caused by sunlight always appear in the section of sky directly opposite the sun.
Rainbows can be observed whenever there are water droplets in the air and sunlight shining from behind the observer at a low altitude angle. The most spectacular rainbow displays happen when half the sky is still dark with raining clouds and the observer is at a spot with clear sky in the direction of the sun. The result is a luminous rainbow that contrasts with the darkened background.
The rainbow's appearance is caused by dispersion of sunlight, which is separated into its component colors when it enters the water droplets. The process is called dispersion. The light is first refracted, or bent, when it enters the water droplet, then is reflected off the back of the droplet, and finally refracted again when leaving the droplet. The overall effect is that the incoming light is separated into its component colors, forming a circle of colors in the sky." (Source: ChatGPT 2023)