Currently, sunspots are no longer such a mysterious phenomenon, as, for example, in the middle of the last millennium. Every inhabitant of our planet is aware that the main source of heat and light is a slight darkening, which is difficult to consider without special devices. But not everyone knows the fact that they lead to solar flares, which can greatly affect the Earth's magnetic field.
Definition
In simple terms, sunspots are dark patches that form on the surface of the sun. It is a mistake to believe that they do not emit bright light, but compared with the rest of the photosphere they are indeed much darker. Their main characteristic is low temperature. Thus, sunspots on the Sun are colder by about 1,500 Kelvin than other areas surrounding them. In fact, they represent the very areas through which magnetic fields come to the surface. Thanks to this phenomenon, we can talk about such a process as magnetic activity. Accordingly, if there are few spots, then this is called a calm period, and when there are a lot of them, then this period will be called active. During the latter, the glow of the Sun is a little brighter due to torches and flocs located around dark areas.
The study
Observation of sunspots has been carried out for a long time, it has its roots back in the era of BC. So, Theophrastus Aquinas in the IV century BC. e. in his works he mentioned their existence. The first sketch of the darkening on the surface of the main star was discovered in 1128, it belongs to John Worcester. In addition, in the ancient Russian works of the XIV century, black solar inclusions are mentioned. Science quickly began to study them in the 1600s. Most scientists of that period adhered to the version that sunspots are moving around the axis of the sun of the planet. But after Galileo invented the telescope, this myth was dispelled. He was the first to find out that spots are integral to the solar structure itself. This event has generated a powerful wave of research and observation, which has not stopped since then. Modern study is amazing in its scope. Over 400 years, progress in this area has become tangible, and now the Royal Belgian Observatory is engaged in counting the number of sunspots, but the disclosure of all the faces of this cosmic phenomenon is still ongoing.
Appearance
Even at school, children are told about the existence of a magnetic field, but usually only the poloidal component is mentioned. But the theory of sunspots also involves the study of a toroidal element, naturally, we are already talking about the magnetic field of the sun. At the Earth it is impossible to calculate, since it does not appear on the surface. Another situation is with the heavenly luminary. Under a set of certain conditions, a magnetic tube floats out through the photosphere. As you might guess, this outburst leads to the formation of sunspots on the surface. Most often this happens in large quantities, which is why group accumulations of spots are most common.
The properties
On average, the temperature of the Sun reaches 6000 K, while at spots it is about 4000 K. However, this does not prevent them from still producing a powerful amount of light. Sunspots and active areas, that is, groups of spots, have different lifetimes. The first live from a couple of days to several weeks. But the latter are much more tenacious and can remain in the photosphere for months. As for the structure of each individual spot, it seems to be difficult. Its central part is called a shadow, which outwardly looks monophonic. In turn, it is surrounded by partial shade, characterized by its variability. As a result of the contact of the cold plasma and the magnetic plasma, oscillations of the substance are noticeable on it. The size of sunspots, as well as their number in groups, can be very diverse.
Solar Activity Cycles
Everyone knows that the level of solar activity is constantly changing. This provision led to the concept of an 11-year cycle. Sunspots, their appearance and number are very closely interconnected with this phenomenon. However, this question remains controversial, since one cycle can vary from 9 to 14 years, and the level of activity constantly changes from century to century. Thus, there may be periods of some lull when there are practically no spots for more than one year. But the opposite can happen when their number is considered abnormal. Previously, the start of the cycle began from the moment of minimal solar activity. But with the advent of advanced technologies, calculus is carried out from the moment when the polarity of the spots changes. Data on past solar activities are available for study, but they are unlikely to become the most faithful assistant in predicting the future, because the nature of the Sun is very unpredictable.
Impact on the planet
It is no secret that magnetic phenomena on the Sun closely interact with our daily lives. The earth is constantly attacked by various stimuli from the outside. The planet is protected from their destructive effects with the help of the magnetosphere and atmosphere. But, unfortunately, they are not able to withstand it completely. Thus, satellites can be out of order, radio communication is disrupted, and astronauts are at increased risk. In addition, radiation affects climate change and even the human appearance. There is such a thing as sunspots on the body that appear under the influence of ultraviolet radiation.
This issue has not yet been studied properly, as is the influence of sunspots on people's daily lives. Another phenomenon that depends on magnetic disturbances can be called the northern lights. Magnetic storms have become one of the most famous effects of solar activity. They represent another external field around the Earth, which is parallel to the constant. Modern scientists even associate increased mortality, as well as exacerbation of diseases of the cardiovascular system with the appearance of this same magnetic field. And among the people, it even gradually began to turn into superstition.