An Analysis of Light Refraction in The Sky and In a Rainbow
Why is the sky blue? How is the rainbow formed? These are questions that have existed for almost as long as humanity started inhabiting earth. The current paper analyzes the scientific explanations of how light is manipulated to manifest beautiful phenomena and optical illusions that define the beauty of the world. The paper revisits various explanations from renowned agencies and authors in a bid to explain what is held to be the real causes of the sky’s blueness and the rainbow.
Why the Sky is Blue
Blue is the colour that defines the sky. When the horizon is clear, without clouds or any other matter, the sky will always appear to be blue to the naked eye. For a very long time few people ever bothered to investigate why the sky remained blue. Earlier astrologers held the belief that the colour symbolized a number of things encoded in the universe. Religious and other philosophical leaders held that it was just how nature was made by the supreme deity who it was held created the entire universe. However, as years have progressed, man has been very inquisitive about why the universe appears to be how it is. It is not very long ago when it was discovered that indeed the sky had no specific colour and that it appeared blue because of very realistic reasons.
The sun is the chief source of light and other forms of energy in earth. Due to the complex chemical reactions that take place in the sun, the earth is able to receive light energy just as does other bodies in the universe. The light that reaches the earth seems white but it is actually made up of all the visible and invisible colours known to man (Erickson). There are up to seven natural colours visible to man and several others which are not naturally visible to the human eye. While there are as many colours as these, experts have been able to point out why the clear sky seems blue and not any other colour. Although several other explanations had been raised to explain why the sky remained blue in most times, there was fronted a realistic explanation which effectively ended the debates that were often associated with the blueness of the clear sky.
Light always travels in a straight line. This is the one of the basic facts about how light from the sun, or any other source, travels in space. However, if an object is placed in the straight path followed by light, it can change its course. For instance, if a mirror is placed in the path followed by light, the light will be reflected to a different direction away from its original path (Met Office). Light can also be scattered like molecules of the gases that exists in the space where light travels. Light can be bent if a prism is placed on the path that it follows while it travels through space. It is this bending of light that has been considered to be the main explanation behind the sky being blue.
Light moves in waves and each colour that is held in the light emanating from the sun moves in different wave lengths. It happens that blue is the light with the shortest wavelength meaning that it travels faster than all the other colours held in the light. When a prism, basically formed by the molecules that block the path of light from the sun, come midway, blue light, given its density and fast wavelength is directly visible to man’s naked eye. This is why the sky appears to be blue at all times except in the evenings and other moments when it appears to be glowing orange or red. The reason for the sky to glow red or orange at some point is because of the increased emission of smoke and other pollutants which distract the flow of light the way it normally moves in space.
A rainbow is an optical illusion seen as a pattern of colours beautifully arranged in the atmosphere. This illusion comes alive when droplets of water are viewed from a specific angle and distance relative to a source of light. A rainbow is never an object and so it can never be touched or located in any specific place. It can only be viewed from a specific angle when droplets of water distract the path of light and the observer views such a distraction from specific angle. In the current section, there will be discussed how exactly a rainbow comes to be seen in a bid to eliminate the misconceptions that have existed all through the time regarding how rainbows and how they occur.
Meteorological experts have recently been able to explain how rainbows are formed. Prior to venturing into the details of how they are formed, meteorologists unanimously uphold that the rainbow phenomenon is an optical illusion that can be formed naturally or by man. In order for it to be formed, light must be reflected, refracted and dispersed. In order to understand the rainbow causation process, it is important to first of all understand the meanings of the three terms as regards to the navigation of light. Reflection of light implies that light bounces back from a surface. Refraction of light simply refers to the bending of light while dispersion of light means the scattering of rays of light to separate the different colours that make it up.
When light rays meet a water droplet on their path, some rays penetrate the water droplet. Due to the reflective surface of water droplets, some light is reflected back. The light that manages to enter into the droplet is diffracted at the surface of the droplet meaning that they lightly change their course. The water droplet also acts as a prism which in turn scatters the rays of light cause them to separate into different colours given the varying wave lengths of light (Theusner). There collision of incident and external rays of light further influences the separation of light which lead to a perfect pattern of colours as per to the varying wavelengths of the light rays.
The arrangement of the different colours of the rainbow does not however reflect how naturally, without reflect, refraction and dispersion, rays of light could be arranged as per their wavelengths. This is because during the light formation of the rainbow, light rays are induced to take up a specific pattern which is as a result of reflection, refraction and dispersion of the light rays.
A rainbow appears to be made up of seven colours. Red appears to be the out most colour in the pattern of colours of the rainbow. Orange follows it in this order of colours then yellow. Green comes as the fourth colour while the fifth colour is blue. Indigo is the sixth colour which is followed by violet (Atmospheric Optics). A normal rainbow must have very clear views of these colours. However, there are variations of rainbows depending on the matter that exists in the atmosphere during the formation of the rainbow. There are times when the rainbow formed takes the shape of a full circle.
There are times also when there are twinned rainbows which mean multiple rainbows can be viewed at the same time and place. There are several other variations of rainbows which call for further study to exhaustively understand why there exist such many variations of this beautiful optical illusion.
The study of nature is very interesting. There are a lot of natural phenomena involving light that can be studied in a bid to satisfy the adventure that such phenomenon elicits. The study of how light is manipulated to form a blue sky has always been very interesting given the various mythological, religious and philosophical beliefs that were coined to the blueness of the sky (Lee and Fraser). Similarly, how the rainbow is formed has always been an interesting topic. How it is naturally possible to attain such a beautiful pattern of colours has always been very interesting. The conclusion of the current paper therefore is that more effort has to be channelled into studying natural phenomena more so that which involves light as all through history, it has been associated with beliefs that shaped the wrong reasoning that existed at one point among the peoples of various societies in the world.
February 2, 2023
February 2, 2023