Sunspots are dark spots on the sun, and they are magnetic in nature. They appear within the photosphere that forms the outermost layer of the sun. This layer is approximately 400km deep, and it is the one that provideы solar radiation. Photosphere has the outer and inner layers. The inner layer’s temperature is about 5900 degrees Kelvin, while the outer boundary is about 4100 degrees Kelvin. Sunspots appear darker, because they are cooler than the surrounding area of the sun. Their dark parts are called the umbra. Sun spots are formed when the sun’s magnetic fields move through the sun. These spots mostly occur in groups and they come and go. Sometimes the sun can have hundreds of spots, while another time they can be almost zero. A single spot can last for a hundred days, while a group of spots can last for fifty days. This paper will discuss the causes of sunspots, their cycle, and the effects, which they have on the Earth.
There are several theories that explain the way sunspots occur (Thomas, 1992). However, not all theories can explain the causes of sunspots. The reason these spots occur is because the sun is a mixture of circulating hot gases that do not move in one piece. The exterior and interior of the sun rotate at different speed. The outer layers rotate quicker at the equator than at the south and north poles. To be precise, a point on the equator only takes 25 days, while a point in the south or north poles takes 36 days to complete the rotation.
After a period of time, the uneven movements between the exterior and interior distort the sun’s magnetic field. Distorting of sun’s magnetic field lines causes these lines to twist (Oliver, 2005). As a result, there is much magnetic power that pushes hot gases below them preventing the heat to rise directly to the surface; hence, the dark spots are formed on the sun’s surface.
The sunspots look darker, because they are cooler, as compared to other parts of the sun (McClure, 2006). In addition, hot gases block the flow of gases around them, making these areas look brighter and hotter than normal. That is why these spots standout more than any other part of the sun. When a person observes the sunspots from the Earth, they tend to move. The movement is due to the movement on the sun’s surface as discussed earlier. The sun takes shorter time to complete its rotation than the Earth. But due to the fact that the sun is 100 times bigger than the Earth, the sunspots tend to move faster than a point on the Earth’s surface. The average size of sunspots is same as that of the Earth, but some are bigger than this planet. The biggest sunspot occurred in 1947, and it was about 18 times more than the size of the Earth (Baker, 2007).
There are several studies that try to explain the sunspot cycle since the late 1800s. These studies have records about the location and size of sunspots. From the gathered information, it shows that sunspots do not appear on the sun surface randomly. Instead, they concentrate in the two bands on both sides of the sun’s equator (Galilei, 2010). Therefore, the intensity, location, and frequency of the sunspots within the bands changes as time goes. The number of sunspots increases roughly from one to fifty after every eleven years. As a new cycle starts, the number decreases almost to zero. The cycles continue to occur after every eleven years. The patterns are called the sunspot cycle. Since 1700, the experts have recorded different lengths of cycles from nine to fourteen years. When the cycle starts, the spots occur in the mid-latitude of the sun, but close to the equator as the cycle progresses.
The cycle occurs because the sun contains hot gasses called plasma that circulate between the sun’s poles and equator for many years (Galilei, 2010). The cycle is asymmetrical with sunspots activities rising faster during the beginning of the cycle and reducing towards the end of it. It reaches a time, when the activities are at the pick. The point is called solar maximum, while the lowest point of the cycle activities is called solar minimum. The lowest point can last for several years. However, the period can stay for more than fifty years before a new cycle starts. There are no reasons to explain why the cycle remains for many years before it occurs. However, several astronomers have explained that long dormant duration also occurs in other stars. The studies about the sunspots cycle continue to be performed as the technology improves. Therefore, we are expecting to have much-detailed information in the future.
Sunspots also cause several effects on the Earth. There are several studies that try to explain the relationship between human behavior and sunspots activities. The relationship varies in the different parts of the cycle. There are many historical events that occurred during the peak of the sunspot cycle (Stetson, 2007). Just to name a few, the First World War was in 1916 to 1918, the civil war in America occurred between 1858 and 1861, and also in 1967 to 1969, the Vietnam War was at the peak. During the three historical events, the sunspot was at maximum. On the other hand, there are very few events reported at minimum sunspot activity. During this time, people do not mind to do great things; they let things go as they come. While there are no extensive researches to prove that there is a relationship between social human activities on the Earth and sunspots cycle, there is a consensus that these two factors are correlated.
Besides social activities relationship, there are also the beliefs that sunspots cycles contribute to cultural flourishes when the cycle is at maximum (Stetson, 2007). There is much of painting, literature, music, and poetry during this period. There are also finding that sunspots have effect on whether a person will get sick or not. Some researchers try to explain that when the cycle is at minimum our immune system and health tend to diminish due to the low stimulation from the sun. At the same time, the cases of occurrence of deadly diseases are high when there is low solar activity. Epidemic diseases, such as diphtheria, dysentery, and typhus are high during this period, because the immune systems tend to be unresponsive. Therefore, diseases can easily gain a foothold in the body.
It is also believed that yellow fever epidemic in the East Africa in the early 1800s happed around minimum sunspots. Besides the general health of the human being, plants are affected as well. There is low yield when the sunspot cycle is at minimum, while there was more yield recorded when the sunspots cycle is at maximum. There is no clear link to prove that there is a relationship between sunspots and change of weather (Sonett, 1991). However, there are several studies that try to link the two. According to these studies, when the sunspot was at minimum, severe winters and cold temperature were recorded in North America and Europe. Nevertheless, no scientists were able to relate the two phenomena.
To sum up, sunspots are dark spots around the sun that are magnetic in nature. The reason these spots occur is due the mixture of hot circulating air in the sun surface. Sunspots have two major cycles; maximum and minimum cycle. There are several impacts of sunspots on the surface of the Earth. First, they are somehow influencing the way people behave. In addition, there are also studies that try to explain how cultural practices, climates, and diseases are correlated with the sunspots.