Rainbows, Mirages and the Color of the Sky and Sunset

There are many spectacular phenomenons in nature including rainbows, mirages, and the color of a beautiful sunrise or sunset. Often, these beautiful images seem unexplainable when actually they can be quite simply elucidated by the natural laws of physics. Rainbows, mirages, and the color of the sky and sunset are examples of how physics can make possible what seems impossible.
It is known that a prism is an object used to break down white light into different spectrums ("Rainbows"). The different spectrums that appear on the other side of the prism are the colors that make up a rainbow: red, orange, yellow, green, blue, indigo, and violet. The prism allows the colors to split up because each spectrum reacts to the class of the prism in a different way ("What Causes a Rainbow"). The glass forces each spectrum to bend, or refract, light at different angles which explains the separation of the colors ("Rainbows").
The idea of rainbows reinforces the concept of prisms. In a rainbow, each raindrop acts as a prism ("Rainbows"). Light enters a raindrop and is refracted through the other side and dispersed into different spectrums ("Rainbows"). Rays of sunlight that are refracted in a raindrop are the rays that create a rainbow ("What Causes a Rainbow"). Every raindrop that adds to the formation of a rainbow is responsible for only one color ("Rainbows"). For example, one raindrop might contribute to the blue ray of a rainbow, while another raindrop may add to the indigo ray. Although each raindrop does act as a prism and splits the sun’s light into all the colors in the spectrum, they are so small; only one beam of light is emitted that contributes to the overall rainbow ("Rainbows"). Raindrops that contribute red light are highest in the sky while those that contribute violet light are lowest. A point called the antisolar point, which is 180 degrees from the sun, determines where a rainbow is formed ("Rainbows"). Consequently, although a rainbow is a beautiful image, it can easily be explained by the laws of physics.
A mirage is another example of a phenomenon that physics helps us to understand ("Mirages"). Basically, mirages are created when there are two separate layers of air that are at different temperatures. The border between warm and cold air can bend light, similarly to a prism because cold air is denser than warm air ("Mirages"). This is essentially how a mirage is created. Often when the boundary between layers of warm and cold air is bent or curved, mirages act as mirror images of images far away ("Mirages"). They can also magnify these distant places and make them look much closer than they really are. A Fata Morgana is a mirage that occurs above water ("Mirages"). Before mirages were identified and explained, people saw them at sea and believed their destination was much closer than it really was. Mirages were even once thought of to be the work of witches ("Mirages").
There is also a physics explanation for the color of the sky at sunrise and sunset ("Blue Skies and White Clouds"). It is often wondered why the sky appears blue in the middle of the day, but red in the morning and evening. This can be explained by the laws of the scattering of light in the atmosphere ("Blue Skies and White Clouds"). During the middle of the day, or noon, the sun’s light passes through a thinner layer of atmosphere than it does during morning or evening. Not much of its light is scattered, which is the reason why it appears to be practically white ("Blue Skies and White Clouds"). Molecules in the atmosphere help to scatter the sun’s light. Humans see the sky as blue because the light being scattered is from the blue end of the spectrum.
This is not true of clouds, because water droplets that make up clouds are of a greater size than the molecules in the atmosphere that scatter the sun’s light. Because these droplets are larger than the molecules in the atmosphere, light is allowed to scatter color equally. Because color is being scattered equally, clouds are seen as white ("Blue Skies and White Clouds").
It is clear that even natural phenomenons such as rainbows, mirages, and the color of sunsets, sunrises, and the sky can be explained by physics’ simple laws. Because physics can help explain these natural occurrences, people are less fooled by mirages that create false images; astounded by the appearance of a rainbow, and puzzled over why the sky is red sometimes and blue at others. By looking at these examples, it is plain to see that physics can explain what was believed to be unexplainable.

Works Cited:

Department of Physics and Astronomy, Arizona State University. "Rainbows." Patterns in Nature: Light and Optics. 1995-2000. 20 Feb 2008. http://www.acept.id.asu.edu/PIN/rdg/rainbow/rainbow.shtml#top

Department of Physics and Astronomy, Arizona State University. "Blue Skies and White Clouds." Patterns in Nature: Light and Optics. 1995-2000. 20 Feb 2008.
http://www.acept.id.asu.edu/PIN/rdg/sky/sky.shtml.

Kryslek, Lee. "Mirages in the Sky." 1996, 1998. 20 Feb 2008. http://www.unmuseum.mus.pa.us/mirage.html.>

"What Causes a Rainbow?" How Stuff Works. 20 Feb 2008. http://www.howstuffworks.com/question41.htm.

Young, Andrew T. "An Introduction to Mirages." 1998-2008. 20 Feb 2008. http://www.mintaka.sdsu.edu/GF/Mirages/mirintro.html.