The article talks about what a solar prominence is, how it can be dangerous for people and how it is classified.
Sun
Life on our planet has existed for almost 4 billion years, and there are a huge number of reasons due to which it was born and continues to exist. This is the climate, the gas composition of the atmosphere, the period of revolution of the planet around its axis, the force of its attraction and, of course, the distance from the Sun. The Earth is located in the so-called habitable zone, that is, at the optimal distance from the star, which ensures the maintenance of a comfortable existence for most biological species. And what happens to planets located too close to the central star of the system can be seen on the example of Mercury - it is completely scorched and empty.
As we can see, all these factors form an extremely complex and branched system, all elements of which must maintain their delicate balance in order for the history of the development of living organisms on our planet to continue.
Prominences
But, of course, there are many obvious and hidden dangers that can deprive this system of the necessary balance. And processes often take place on the Sun,which can pose a danger to all living things and not only. For example, the so-called solar or magnetic storms. Weather-sensitive people and various equipment often suffer from them. During such storms, prominences break away from the Sun and rush to the nearest planets. Fortunately, most of them are not so great as to lead to tragic consequences. Why are prominences dangerous, and what is it? We will talk about this in this article.
Definition
Prominences are dense condensations of colder matter compared to the rest of the Sun's surface. During periods of activity, they rise above the surface of the star and are held there by its magnetic field. Simply put, prominences are giant fountains of hot solar matter that are held together by the star's gravity. But sometimes, during times of especially strong solar activity, plasma flows fly out of the solar photosphere and rush in all directions, including towards our planet. This phenomenon is called a magnetic or solar storm.
Description
One of the first scientific references to prominences is associated with a solar eclipse that occurred in 1185. But due to the imperfection of instruments and the poor development of astrophysics, the scientific study of prominences began in the middle of the 19th century. In 1868, Pierre Jansen, using a new method of observing this phenomenon without a solar eclipse, concluded that they exist in gaseouscondition.
Because of their nature, prominences are something that has been well studied only using the achievements of scientific and technological progress: time-lapse photography and artificial near-Earth observation satellites.
They are clearly visible during total solar eclipses. Such phenomena are observed by means of special instruments: prominence telescopes, filters, coronographs, chromospheric telescopes, and others. If we consider the projection of prominences on the solar disk, they look like dark elongated filaments of various thicknesses. So prominences are a phenomenon that can only be observed with a conventional telescope during a total solar eclipse.
In fact, we figured out what solar prominences are, now let's look at their types.
Views
If we talk about the appearance, then the prominences are ragged structures that look like filaments or plasma clots of various shapes. They are also constantly moving and changing their shape. Their classification is carried out according to dynamic or morphological characteristics. Consider their classification according to their external appearance, features of the movement of matter and speed:
- Calm. In them, matter moves most slowly. The form is also changing very slowly. If we talk about the time of their life, then it ranges from several weeks to several months. Occur in all heliographic latitudes. Most often they can be observed near sunspots of the late stage of development. The temperature is approximately 15,000 degrees Celsius.
- Active. Such a prominence, photowhich can be seen below, differs in that the plasma flows from the base of the geyser towards the photosphere, as well as from one prominence to another, move at a very high speed. Their temperature is 25,000 degrees Celsius. And by the way, many active prominences are formed from quiet ones, but in this case, their existence time is from several minutes to a day.
- Eruptive. If we talk about appearance, then most of all, such prominences resemble huge fountains more than one and a half million kilometers above the surface of our star. The speed of plasma movement reaches hundreds of kilometers per hour, and their shape changes very quickly. They do not last long, and as they increase in height, they gradually dissipate completely.
- Loop-shaped prominences appear as small clouds above the chromosphere. Usually, over time, they merge into one large cloud, which then emits jets of hot gas towards the chromosphere. Such phenomena rarely exist for more than a few hours.
So now we know that the solar corona has prominences, and what kinds of them exist.
Theory of occurrence
Despite the fact that solar activity has been studied for a very long time, there is still no unified and complete theory that would explain the fact of the occurrence of prominences and all other phenomena related to them. In part, all this is explained by the combined action of electric and magnetic forces with the force of gravity. Sun.
The chemical composition of the prominence clearly corresponds to the layer from which it was formed. But the physical conditions for the existence of a phenomenon are often associated with the chemical composition. For example, the lines of hydrogen and ionized calcium predominate in the spectrum of quiet prominences. And in those associated with sunspots, the lines of various metals are most clearly distinguished.
The fact of the long existence of some of their varieties indicates that the substance is held by the magnetic force of the star. This assumption was confirmed by a number of spectroscopic observations.
Danger
As we have already discussed, a prominence is an element of the activity of the sun's chromosphere and some of its physical processes. First of all, the danger is represented by those that break away from the surface of the star and rush into interstellar space. Depending on the strength, they can disable satellites in Earth orbit and even kill the crew of the ISS. Reacting with the magnetosphere of our planet, prominences also form powerful magnetic storms that adversely affect the well-being of weather-sensitive people, interfere with the operation of radio communication systems and various electronic equipment. Luckily, prominences that can break away from the surface of the Sun and cause such damage are extremely rare.
But, if we consider the saddest option, when the prominence will be large, it can severely damage the atmosphere of our planet or completely destroy everythingalive.
