An atmosphere is capable of generating certain colorful formations when subjected to different light conditions. Some of these burst of color includes; sundogs, pillars, moon dogs and parhelic circles. It is important to note that all these colorful formations occur when the rays of light traverse mediums of different optical densities. Since light is an electromagnetic radiation, its visibility to the eye depends on transmission wavelength. Based on this concept, the ice crystals and water droplets in the atmosphere break the light frequencies into distinct colors that can be visualized by an eye. Therefore, the colorful atmospheric formations are majorly caused by both refraction and reflection mechanisms on the rays of light.
A sundog is a colored spot that occurs on either side of the sun at 22-degree separation ( Tufaile, Vanderelli & Tufaile, 2017). Their color usually becomes red closest to the sun and blue on the outer regions. Whenever cirrus or cirrostratus clouds move across the sky, the ice crystals that form these clouds act as prisms in color separation. Sundogs are formed when light traverses the hexagonal ice crystals ( Tufaile et al., 2016). As the clouds drift across the sky so are the hexagonal ice crystals. When these ice plates float in a horizontal position, they are hit by rays of light which are refracted at an angle of 60 ° ( Tufaile, Vanderelli & Tufaile, 2017). According to Tufaile et al. (2016), the two refractions then deviate by 22°, but this magnitude may vary based on the ray’s angle of incidence. However, when the light ray is less refracted a red color is visualized by the eye ( Tufaile et al., 2016). This is the main reason sundogs appear reddish closest to the sun. The blue color, on the other hand, is formed by heavy refraction of the light rays ( Tufaile et al., 2016). Tufaile et al. (2016) indicate that when the hexagonal crystal plates are moved gently downwards, the rays from the sun are refracted thus making which the sundogs to appear on both sides of the sun. It is also worth noting that taller and larger sundogs are produced by huge and wobbling hexagonal ice crystals as shown in the figure below. Sundogs are usually visualized at sunrise and sunset, but other conditions in the sky can permit their formation. Since this phenomenon requires ice crystals for its formation, it is usually associated with chilly weather. However, they are more common during winter.
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Fig 1. Showing a slightly dim sundog (Tufaile et al., 2016)
Fig 2. Showing a bright sundog (Tufaile et al., 2016)
Mood dogs, on the other hand, are bright colored formations that appear around the moon. Even though they are formed in the same way as sun dogs, they rarely occur. In their formation, the ice crystals must be suspended in the atmosphere. This phenomenon usually occurs in the winter when a chilly weather is experienced, but it can also occur in other periods of the year as long as the right conditions are met ( Simpson, 2018). According to Simpson (2018), as the cirrus or cirrostratus clouds drift in the atmosphere, the suspended hexagonal ice crystals are also moved horizontally. If the light rays reflected from the moon fall on the ice crystals, they are refracted at a separation angle of 22 degrees ( Simpson, 2018). The refracted rays of light form the respective arcs of light on the right and left parts of the moon. However, for this process to be successful, the moon is expected to be in full size, slightly lower in the sky and more bright ( Simpson, 2018). One major notable difference with the sun dogs is that the moons dogs tend to be dimmer. Also, they are not as colorful as the sun dogs due to the lower light intensity generated by the moon. Also, Simpson (2018) postulates that at times, sun dogs can occur with moon dogs, but they normally appear as small arcs of light at either side of the moon.
Fig 3. Showing A Moon Dog (Simpson, 2018).
Sun pillars are other atmospheric formations that appear as vertical shafts of light drifting downwards or upwards from the sun. This phenomenon is very common during sunset and sunrise. Just like sun dogs and moon dogs they are formed through the refraction of light by the suspended ice crystals. However, they are usually visualized in the sunny and chilly seasons ( Tufaile et al., 2016) . Sun pillars are similar to sundogs and moon dogs since they are formed by the cirrostratus clouds. Based on this concept, sun pillars are formed by the interaction of light rays with plate-like crystals. As the clouds drift across the sky, the plate-like ice crystals ranging from large to snow-flakes wobble thus scattering the light rays. However, the scattered light rays are blocked by other falling crystals which prevent the formation of arcs like other halos discussed. Tufaile et al. (2016) states that, when the plate-like crystals are arranged horizontally, the light rays’ incident on the upper faces initiates multiple internal reflections which generate light beams on the opposite surface based the number of reflections. The integration of light reflected from the crystals is equivalent to the one received from the sun ( Tufaile et al., 2016) . Based on this concept, the light rays appear like huge bright shafts of light drifting upwards or downwards from the sun. Even though the pillar is generated through reflection, it adopts the reddish color from the incident sun rays as shown in fig 4 below.
Fig 4. Showing A Sun Pillar (Tufaile et al., 2016).
Lastly, a parhelic circle is a white band of light circulating a section or the entire sky. In comparison to the other halos it is formed through reflection, and this is the main reason it appears as a white ring. However, a parhelic circle can also exhibit other color formations. For instance, it may appear greenish or bluish at 120 degrees of the parhelia or reddish at its fringes ( Borchardt & Selmke, 2015). In comparison to sundogs, parhelic circles occur rarely and can be formed by both the sun and the moon. They are formed when the sun increases its elevation to about 41 degrees, forcing the created sundogs to circumscribe into a circle ( Borchardt & Selmke, 2015) . Like other halos, it is formed when the light beams are reflected by the vertical hexagonal ice crystals in the atmosphere. In contrast to the moons dogs and sundogs, the parhelic circle is formed by either internal or external reflection of light rays by the suspended ice crystals. If the reflection of the beam of light is externally executed, the parhelic circle tends to be near the sun, but in case an internal reflection occurs; they occur away from the sun ( Tufaile & Tufaile, 2015). As the beam of light hits the ice crystals, it is distributed through a 1-3-2 and 1-3-8-2 pattern. In this pattern, 1 denotes the upper face, 2 the bottom face and 3-8 the other faces on the sides of the crystals block that occur in a counterclockwise manner ( Borchardt & Selmke, 2015) . For example, the above-enumerated pattern is responsible for the bluish spot in the circle ( Borchardt & Selmke, 2015) . This phenomenon is associated with sunny and chilly weather.
Fig 5. Showing A Parhelic Circle (Tufaile & Tufaile, 2015).
Some of the huge cyclones experienced on the earth surface do not even warrant the smallest storms experienced in Jupiter and Saturn. However, the atmospheric storms experienced in both Jupiter and Saturn harbor lots of similarities. In both planets, the storms are not fed by oceans but the rising warm air which rises through buoyancy. The integration of this air with dust particles create a huge storm accompanied by a thunderstorm that is much higher than what is experienced on the earth surface. According to Bolton et al., (2017) the storm experienced in Jupiter is three times the size of the earth surface. It is also, worth noting that the hurricanes experienced on the earth surface are mainly caused by sun energy. However, in Saturn and Jupiter, their rising air is majorly contributed by the heat generated in their core ( Bolton et al., 2017) . While the earth atmosphere is highly composed of oxygen, Jupiter and Saturn have hydrogen composition of 90% and 95% respectively ( Meredith, Cowley & Nichols, 2014). Even though the two planets harbor lots of similarities, they differ in their respective sizes of storm. For instance, Saturn has hexagonally shaped storms at its two poles, but Jupiter has numerous storms that support the main storm at its red hole ( Meredith, Cowley & Nichols, 2014). The storm found in Saturn take longer to grow as opposed to the one found in Jupiter. Saturn boasts of a high atmospheric pressure caused by its stronger, core which pulls off all the gases manifested in the nearby stars ( Meredith, Cowley & Nichols, 2014). Therefore, for a storm to be noticeable in Saturn, it takes a longer time for the dust particles to accumulate. In comparison to the cyclones experienced on the earth surface, the storms experienced in Jupiter and Saturn have much higher speed. As depicted by García-Melendo et al. (2013) , Saturn has a much higher wind speed of 1200mph as compared to 250mph in Saturn and 231mph on the earth surface. This concept confirms how fatal and destructive the storm of the two planets are in comparison to what is experienced on the earth surface
References
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