The Sun's atmosphere is 90% hydrogen. The farthest part of it from the surface is called the corona of the Sun, it is clearly visible during total solar eclipses. The temperature of the corona reaches 1.5-2 million K, and the gas of the corona is completely ionized. At such a plasma temperature, the thermal velocity of protons is about 100 km/s, and that of electrons is several thousand kilometers per second. To overcome solar attraction, an initial velocity of 618 km/s, the second space velocity of the Sun, is sufficient. Therefore, there is a constant leakage of plasma from the solar corona into space. This flow of protons and electrons is called the solar wind.
Having overcome the attraction of the Sun, the particles of the solar wind fly along straight trajectories. The speed of each particle with the removal almost does not change, but it can be different. This speed depends mainly on the state of the solar surface, on the "weather" on the Sun. On average, it is v ≈ 470 km/s. The solar wind travels the distance to the Earth in 3-4 days. The density of particles in it decreases in inverse proportion to the square of the distance to the Sun. At a distance equal to the radius of the earth's orbit, in 1 cm 3, on average, there are 4 protons and 4 electrons.
The solar wind reduces the mass of our star - the Sun - by 10 9 kg per second. Although this number seems large on Earth scales, in reality it is small: the decrease in the solar mass can only be noticed over times thousands of times longer than the current age of the Sun, which is approximately 5 billion years.
The interaction of the solar wind with the magnetic field is interesting and unusual. It is known that charged particles usually move in a magnetic field H along a circle or along helical lines. This is true, however, only when the magnetic field is strong enough. More precisely, for the motion of charged particles in a circle, it is necessary that the energy density of the magnetic field H 2 /8π be greater than the kinetic energy density of the moving plasma ρv 2 /2. In the solar wind, the situation is reversed: the magnetic field is weak. Therefore, charged particles move in straight lines, while the magnetic field is not constant, it moves along with the flow of particles, as if carried away by this flow to the periphery of the solar system. The direction of the magnetic field in the entire interplanetary space remains the same as it was on the surface of the Sun at the time of the release of the solar wind plasma.
The magnetic field, as a rule, changes its direction 4 times when going around the equator of the Sun. The sun rotates: points on the equator make a revolution in T \u003d 27 days. Therefore, the interplanetary magnetic field is directed in spirals (see Fig.), and the whole picture of this pattern rotates after the rotation of the solar surface. The rotation angle of the Sun changes as φ = 2π/T. The distance from the Sun increases with the speed of the solar wind: r = vt. Hence the equation of spirals in fig. has the form: φ = 2πr/vT. At a distance of the Earth's orbit (r = 1.5 10 11 m), the angle of inclination of the magnetic field to the radius vector is, as can be easily verified, 50°. On average, this angle is measured by spacecraft, but not quite close to the Earth. Near the planets, however, the magnetic field is arranged differently (see Magnetosphere).
Constant radial flux of solar plasma. crowns in interplanetary production. The flow of energy coming from the bowels of the Sun heats the plasma of the corona up to 1.5-2 million K. Post. heating is not balanced by the loss of energy due to radiation, since the corona is small. Excess energy means. degree carry away h-tsy S. century. (=1027-1029 erg/s). The crown, therefore, is not in hydrostatic. equilibrium, it is constantly expanding. According to the composition of S. century. does not differ from the plasma of the corona (S. century contains chiefly arr. protons, electrons, a few helium nuclei, oxygen ions, silicon, sulfur, and iron). At the base of the corona (10,000 km from the solar photosphere) h-tsy have a radial order of hundreds of m / s, at a distance of several. solar radii, it reaches the speed of sound in plasma (100 -150 km / s), near the Earth's orbit, the speed of protons is 300-750 km / s, and their space. - from several h-ts up to several tens of fractions in 1 cm3. With the help of interplanetary space. stations it was found that up to the orbit of Saturn, the flux density of the h-c S. century. decreases according to the law (r0/r)2, where r is the distance from the Sun, r0 is the initial level. S. v. carries with it the loops of the lines of force of the suns. magn. fields, to-rye form interplanetary magn. . Combination of radial movement of h-c S. century. with the rotation of the Sun gives these lines the shape of spirals. Large-scale structure of the magnet. The field in the vicinity of the Sun has the form of sectors, in which the field is directed away from the Sun or towards it. The size of the cavity occupied by the SV is not exactly known (its radius, apparently, is not less than 100 AU). At the boundaries of this cavity dynamic. S. v. must be balanced by the pressure of interstellar gas, galactic. magn. fields and galactic space rays. In the vicinity of the Earth, the collision of the flow of c-c S. v. with geomagnetic field generates a stationary shock wave in front of the Earth's magnetosphere (from the side of the Sun, Fig.).
S. v. as if it flows around the magnetosphere, limiting its extent in the pr-ve. Changes in the intensity of S. century associated with solar flares, yavl. main the cause of geomagnetic disturbances. fields and magnetospheres (magnetic storms).
Over the Sun loses with S. in. \u003d 2X10-14 part of its mass Msun. It is natural to assume that an outflow of water, similar to S. V., also exists in other stars (""). It should be especially intense for massive stars (with a mass = several tens of Msolns) and with a high surface temperature (= 30-50 thousand K) and for stars with an extended atmosphere (red giants), because in In the first case, parts of a highly developed stellar corona have a sufficiently high energy to overcome the attraction of the star, and in the second, they have a low parabolic. speed (escape speed; (see SPACE SPEEDS)). Means. mass losses with the stellar wind (= 10-6 Msol/yr and more) can significantly affect the evolution of stars. In turn, the stellar wind creates "bubbles" of hot gas in the interstellar medium - sources of X-rays. radiation.
Physical Encyclopedic Dictionary. - M.: Soviet Encyclopedia. . 1983 .
SOLAR WIND - a continuous flow of plasma of solar origin, the Sun) into interplanetary space. At high temperatures, which exist in the solar corona (1.5 * 10 9 K), the pressure of the overlying layers cannot balance the gas pressure of the corona substance, and the corona expands.
The first evidence of the existence of post. plasma flux from the Sun obtained by L. Birman (L. Biermann) in the 1950s. on the analysis of the forces acting on the plasma tails of comets. In 1957, J. Parker (E. Parker), analyzing the conditions of equilibrium of the substance of the crown, showed that the crown cannot be in hydrostatic conditions. Wed S.'s characteristics are given in table. 1. Flows of S. in. can be divided into two classes: slow - with a speed of 300 km / s and fast - with a speed of 600-700 km / s. Fast streams come from regions of the solar corona, where the structure of the magnetic. field is close to radial. coronal holes. Slow streams. in. associated, apparently, with the areas of the crown, in which there is a means Tab. one. - Average characteristics of the solar wind in Earth's orbit
Speed | |
Proton concentration | |
Proton temperature | |
Electron temperature | |
Magnetic field strength | |
Python Flux Density.... | 2.4*10 8 cm -2 *c -1 |
Kinetic energy flux density | 0.3 erg*cm -2 *s -1 |
Tab. 2.- Relative chemical composition of the solar wind
Relative content |
|
Relative content |
|
In addition to the main the components of S. century - protons and electrons, - particles were also found in its composition. Measurements of ionization. temperature of ions S. century. make it possible to determine the electron temperature of the solar corona.
In S. century. differences are observed. types of waves: Langmuir, whistlers, ion-sound, Plasma waves). Some of the Alfvén type waves are generated on the Sun, and some are excited in the interplanetary medium. The generation of waves smooths out the deviations of the function of the distribution of particles from the Maxwellian and, in conjunction with the influence of the magnetic. field on the plasma leads to the fact that S. century. behaves like a continuum. Waves of the Alfvén type play a large role in the acceleration of the small components of C. 
Rice. 1. Massive solar wind. On the horizontal axis - the ratio of the mass of the particle to its charge, on the vertical - the number of particles registered in the energy window of the device for 10 s. The numbers with a "+" sign indicate the charge of the ion.
S.'s stream in. is supersonic in relation to the speeds of those types of waves, to-rye provide eff. energy transfer in S. century. (Alvenov, sound). Alvenovskoye and sound Mach number C. in. 7. When flowing around S. in. obstacles capable of effectively deflecting it (the magnetic fields of Mercury, Earth, Jupiter, Saturn or the conducting ionospheres of Venus and, apparently, Mars), an outgoing bow shock wave is formed. waves, which allows it to flow around an obstacle. At the same time in S. century. a cavity is formed - the magnetosphere (own or induced), the shape and size of the swarm are determined by the balance of magnetic pressure. field of the planet and the pressure of the flowing plasma flow (see Fig. Magnetosphere of the Earth, Magnetosphere of planets). In the case of interaction S. century. with a non-conducting body (eg, the Moon), a shock wave does not occur. The plasma flow is absorbed by the surface, and a cavity is formed behind the body, which is gradually filled with plasma C. in.
The stationary process of corona plasma outflow is superimposed by nonstationary processes associated with flares on the sun. With strong outbreaks, matter is ejected from the bottom. regions of the corona into the interplanetary medium. magnetic variations). 
Rice. 2. Propagation of an interplanetary shock wave and ejecta from a solar flare. The arrows show the direction of motion of the solar wind plasma,
Rice. 3. Types of solutions to the corona expansion equation. The speed and distance are normalized to the critical speed vc and the critical distance Rc. Solution 2 corresponds to the solar wind.
The expansion of the solar corona is described by a system of ur-tions of conservation of mass, v k) on some critical. distance R to and subsequent expansion at supersonic speed. This solution gives a vanishingly small value of the pressure at infinity, which makes it possible to match it with the low pressure of the interstellar medium. Yu. Parker called the course of this type S. century. 
, where m is the mass of the proton, is the adiabatic index, is the mass of the Sun. On fig. 4 shows the change in expansion rate with heliocentric. thermal conductivity, viscosity, 
Rice. 4. Solar wind velocity profiles for the isothermal corona model at various values of coronal temperature.
S. v. provides the main outflow of thermal energy of the corona, since heat transfer to the chromosphere, el.-mag. coronas and electronic thermal conductivitypp. in. insufficient to establish the thermal balance of the corona. Electronic thermal conductivity provides a slow decrease in the temperature of S. in. with distance. luminosity of the sun.
S. v. carries the coronal magnetic field with it into the interplanetary medium. field. The lines of force of this field frozen into the plasma form the interplanetary magnetic field. field (MMP). Although the intensity of the IMF is small and its energy density is approx. 1% of the density of the kinetic. energy S. v., it plays an important role in the thermodynamics of S. in. and in the dynamics of S.'s interactions. with the bodies of the solar system, as well as the flows of S. in. between themselves. Combination of S.'s expansion. with the rotation of the Sun leads to the fact that the magn. the lines of force frozen in the S. century have the form, B R and the azimuth components of the magnetic. fields change differently with distance near the plane of the ecliptic: 
where - ang. sun rotation speed and - radial component of velocity c., index 0 corresponds to the initial level. At a distance of the Earth's orbit, the angle between the direction of the magnetic. fields and R about 45°. At large L magn. 
Rice. 5. The shape of the field line of the interplanetary magnetic field. - the angular velocity of the rotation of the Sun, and - the radial component of the plasma velocity, R - the heliocentric distance.
S. v., arising over the regions of the Sun with decomp. magnetic orientation. fields, speed, temp-pa, concentration of particles, etc.) also cf. regularly change in the cross section of each sector, which is associated with the existence of a fast S. flow within the sector. The boundaries of the sectors are usually located in the intraslow flow of S. at. Most often, 2 or 4 sectors are observed, rotating with the Sun. This structure which is formed at S.'s pulling out of century. large-scale magnetic field of the crown, can be observed for several. revolutions of the sun. The sectoral structure of the IMF is a consequence of the existence of a current sheet (TS) in the interplanetary medium, which rotates together with the Sun. TS creates a magnetic surge. fields - radial IMF have different signs on different sides of the vehicle. This TS, predicted by H. Alfven, passes through those sections of the solar corona, which are associated with active regions on the Sun, and separates these regions from decomp. signs of the radial component of the solar magnet. fields. The TC is located approximately in the plane of the solar equator and has a folded structure. The rotation of the Sun leads to the twisting of the CS folds into a spiral (Fig. 6). Being near the plane of the ecliptic, the observer turns out to be either above or below the CS, due to which he falls into sectors with different signs of the IMF radial component.
Near the Sun in the N. century. there are longitudinal and latitudinal velocity gradients of collisionless shock waves (Fig. 7). First, a shock wave is formed that propagates forward from the boundary of the sectors (a direct shock wave), and then a reverse shock wave is formed that propagates towards the Sun. 
Rice. 6. Shape of the heliospheric current sheet. Its intersection with the plane of the ecliptic (tilted to the equator of the Sun at an angle of ~ 7°) gives the observed sectoral structure of the interplanetary magnetic field.
Rice. 7. Structure of the sector of the interplanetary magnetic field. The short arrows show the direction of the solar wind, the arrow lines show the magnetic field lines, the dash-dotted line shows the sector boundaries (the intersection of the figure plane with the current sheet).
Since the speed of the shock wave is less than the speed of the SV, it carries away the reverse shock wave in the direction away from the Sun. Shock waves near the sector boundaries are formed at distances of ~1 AU. e. and can be traced to distances of several. a. e. These shock waves, like interplanetary shock waves from solar flares and circumplanetary shock waves, accelerate particles and are thus a source of energetic particles.
S. v. extends to distances of ~100 AU. That is, where the pressure of the interstellar medium balances the dynamic. S.'s pressure The cavity swept up by S. in. interplanetary environment). ExpandingS. in. together with the magnet frozen into it. field prevents penetration into the solar system galactic. space rays of low energies and leads to cosmic variations. beams of high energy. A phenomenon similar to S. V., found in some other stars (see. Stellar wind).
Lit.: Parker E. N., Dynamics in the interplanetary medium, O. L. Vaisberg.
Physical encyclopedia. In 5 volumes. - M.: Soviet Encyclopedia. Editor-in-Chief A. M. Prokhorov. 1988 .
See what "SOLAR WIND" is in other dictionaries:
SOLAR WIND, the flow of solar corona plasma that fills the solar system up to a distance of 100 astronomical units from the Sun, where the pressure of the interstellar medium balances the dynamic pressure of the flow. The main composition is protons, electrons, nuclei ... Modern Encyclopedia
SOLAR WIND, a steady flow of charged particles (mainly protons and electrons) accelerated by the high temperature of the solar CORONA to speeds large enough for the particles to overcome the gravity of the Sun. The solar wind deflects... Scientific and technical encyclopedic dictionary
V.B. Baranov, Lomonosov Moscow State University M.V. Lomonosov
The article deals with the problem of supersonic expansion of the solar corona (solar wind). Four main problems are analyzed: 1) the reasons for the outflow of plasma from the solar corona; 2) whether such an outflow is homogeneous; 3) change in solar wind parameters with distance from the Sun and 4) how the solar wind flows out into the interstellar medium.
Introduction
Almost 40 years have passed since the American physicist E. Parker theoretically predicted a phenomenon called the "solar wind" and which, a couple of years later, was experimentally confirmed by the group of the Soviet scientist K. Gringauz using instruments mounted on the Luna- 2" and "Luna-3". The solar wind is a stream of fully ionized hydrogen plasma, that is, a gas consisting of electrons and protons of approximately the same density (quasi-neutrality condition), which moves away from the Sun at a high supersonic speed. In the Earth's orbit (one astronomical unit (AU) from the Sun), the speed VE of this stream is approximately 400-500 km/s, the concentration of protons (or electrons) ne = 10-20 particles per cubic centimeter, and their temperature Te is approximately 100,000 K (the electron temperature is somewhat higher).
In addition to electrons and protons, alpha particles (of the order of a few percent), a small amount of heavier particles, and a magnetic field were detected in interplanetary space, the average value of the induction of which turned out to be on the Earth's orbit of the order of several gammas (1
= 10-5 Gs).A bit of history related to the theoretical prediction of the solar wind
During the not so long history of theoretical astrophysics, it was believed that all the atmospheres of stars are in hydrostatic equilibrium, that is, in a state when the force of the gravitational attraction of a star is balanced by the force associated with the pressure gradient in its atmosphere (with a change in pressure per unit distance r from the center stars). Mathematically, this equilibrium is expressed as an ordinary differential equation
| (1) |
where G is the gravitational constant, M* is the mass of the star, p is the atmospheric gas pressure,
is its mass density. If the temperature distribution T in the atmosphere is given, then from the equilibrium equation (1) and the equation of state for an ideal gas| (2) |
where R is the gas constant, the so-called barometric formula is easily obtained, which in the particular case of a constant temperature T will have the form
| (3) |
In formula (3), p0 is the pressure at the base of the stellar atmosphere (at r = r0). It can be seen from this formula that for r
, that is, at very large distances from the star, the pressure p tends to a finite limit, which depends on the value of the pressure p0.Since it was believed that the solar atmosphere, as well as the atmospheres of other stars, is in a state of hydrostatic equilibrium, its state was determined by formulas similar to formulas (1), (2), (3) . Taking into account the unusual and not yet fully understood phenomenon of a sharp increase in temperature from about 10,000 degrees on the surface of the Sun to 1,000,000 degrees in the solar corona, Chapman (see, for example) developed the theory of a static solar corona, which should have smoothly passed into the interstellar medium surrounding the solar system.
However, in his pioneering work, Parker noticed that the pressure at infinity, obtained from a formula like (3) for the static solar corona, turns out to be almost an order of magnitude greater than the pressure value that was estimated for interstellar gas from observations. To eliminate this discrepancy, Parker suggested that the solar corona is not in static equilibrium, but is continuously expanding into the interplanetary medium surrounding the Sun. At the same time, instead of the equilibrium equation (1), he proposed to use a hydrodynamic equation of motion of the form
| (4) |
where in the coordinate system associated with the Sun, the value V is the radial velocity of the plasma. Under
refers to the mass of the sun.For a given temperature distribution Т, the system of equations (2) and (4) has solutions of the type shown in Figs. 1. In this figure, a denotes the speed of sound, and r* is the distance from the origin at which the gas speed is equal to the speed of sound (V = a). Obviously, only curves 1 and 2 in Figs. 1 have a physical meaning for the problem of gas outflow from the Sun, since curves 3 and 4 have non-unique velocities at each point, and curves 5 and 6 correspond to very high velocities in the solar atmosphere, which is not observed in telescopes. Parker analyzed the conditions under which a solution corresponding to curve 1 is implemented in nature. He showed that in order to match the pressure obtained from such a solution with the pressure in the interstellar medium, the most realistic case is the transition of gas from a subsonic flow (at r< r*) к сверхзвуковому (при r >r*), and called this current the solar wind. However, this assertion was disputed in the work by Chamberlain, who considered the most realistic solution corresponding to curve 2, which describes the subsonic "solar breeze" everywhere. At the same time, the first experiments on spacecraft (see, for example,), which discovered supersonic gas flows from the Sun, did not seem, judging by the literature, to Chamberlain sufficiently reliable.
| Rice. 1. Possible solutions of one-dimensional equations of gas dynamics for the velocity V of gas flow from the surface of the Sun in the presence of a gravitational force. Curve 1 corresponds to the solution for the solar wind. Here a is the speed of sound, r is the distance from the Sun, r* is the distance at which the gas speed is equal to the speed of sound, is the radius of the Sun. |
The history of experiments in outer space brilliantly proved the correctness of Parker's ideas about the solar wind. Detailed material on the theory of the solar wind can be found, for example, in the monograph.
Ideas about the uniform outflow of plasma from the solar corona
From the one-dimensional equations of gas dynamics, one can obtain the well-known result: in the absence of body forces, a spherically symmetric gas flow from a point source can be either subsonic or supersonic everywhere. The presence of the gravitational force (right side) in equation (4) leads to the appearance of solutions like curve 1 in Fig. 1, that is, with the transition through the speed of sound. Let us draw an analogy with the classical flow in the Laval nozzle, which is the basis of all supersonic jet engines. Schematically, this flow is shown in Fig. 2.
| Rice. Fig. 2. Scheme of flow in the Laval nozzle: 1 - a tank, called a receiver, into which very hot air is supplied at a low speed, 2 - the area of the geometric compression of the channel in order to accelerate the subsonic gas flow, 3 - the area of the geometric expansion of the channel in order to accelerate the supersonic flow. |
Tank 1, called the receiver, is supplied with gas heated to a very high temperature at a very low speed (the internal energy of the gas is much greater than its kinetic energy of directed motion). By means of a geometric compression of the channel, the gas is accelerated in region 2 (subsonic flow) until its speed reaches the speed of sound. For its further acceleration, it is necessary to expand the channel (region 3 of the supersonic flow). In the entire flow region, gas is accelerated due to its adiabatic (without heat supply) cooling (the internal energy of chaotic motion is converted into the energy of directed motion).
In the considered problem of the formation of the solar wind, the role of the receiver is played by the solar corona, and the role of the walls of the Laval nozzle is played by the gravitational force of solar attraction. According to Parker's theory, the transition through the speed of sound should occur somewhere at a distance of several solar radii. However, an analysis of the solutions obtained in the theory showed that the temperature of the solar corona is not enough for its gas to be accelerated to supersonic speeds, as is the case in the Laval nozzle theory. There must be some additional source of energy. Such a source is currently considered to be the dissipation of wave motions always present in the solar wind (sometimes called plasma turbulence), superimposed on the mean flow, and the flow itself is no longer adiabatic. Quantitative analysis of such processes still requires further research.
Interestingly, ground-based telescopes detect magnetic fields on the surface of the Sun. The average value of their magnetic induction B is estimated at 1 G, although in individual photospheric formations, for example, in spots, the magnetic field can be orders of magnitude greater. Since plasma is a good conductor of electricity, it is natural that the solar magnetic fields interact with its flows from the Sun. In this case, a purely gas-dynamic theory gives an incomplete description of the phenomenon under consideration. The influence of the magnetic field on the flow of the solar wind can only be considered within the framework of a science called magnetohydrodynamics. What are the results of such considerations? According to pioneering work in this direction (see also ), the magnetic field leads to the appearance of electric currents j in the plasma of the solar wind, which, in turn, leads to the appearance of a ponderomotive force j x B, which is directed in a direction perpendicular to the radial direction. As a result, the solar wind has a tangential velocity component. This component is almost two orders of magnitude smaller than the radial one, but it plays a significant role in the removal of angular momentum from the Sun. It is assumed that the latter circumstance may play a significant role in the evolution not only of the Sun, but also of other stars in which a "stellar wind" has been discovered. In particular, to explain the sharp decrease in the angular velocity of stars of the late spectral type, the hypothesis of the transfer of rotational momentum to the planets formed around them is often invoked. The considered mechanism of the loss of the angular momentum of the Sun by the outflow of plasma from it opens up the possibility of revising this hypothesis.
Imagine that you heard the words of the announcer in the weather forecast: “Tomorrow the wind will pick up sharply. In this regard, interruptions in the operation of radio, mobile communications and the Internet are possible. US space mission delayed. Intense auroras are expected in the north of Russia…”.
You will be surprised: what nonsense, what does the wind have to do with it? But the fact is that you missed the beginning of the forecast: “Last night there was a solar flare. A powerful stream of solar wind is moving towards the Earth…”.
Ordinary wind is the movement of air particles (molecules of oxygen, nitrogen and other gases). A stream of particles also rushes from the Sun. It is called the solar wind. If you do not delve into hundreds of cumbersome formulas, calculations and heated scientific disputes, then, in general, the picture appears as follows.
Thermonuclear reactions are going on inside our luminary, heating up this huge ball of gases. The temperature of the outer layer - the solar corona reaches a million degrees. This causes the atoms to move at such speed that when they collide, they smash each other to smithereens. It is known that a heated gas tends to expand and occupy a larger volume. Something similar is happening here. Particles of hydrogen, helium, silicon, sulfur, iron and other substances scatter in all directions.
They are gaining more and more speed and in about six days they reach the near-Earth borders. Even if the sun was calm, the speed of the solar wind reaches here up to 450 kilometers per second. Well, when the solar flare erupts a huge fiery bubble of particles, their speed can reach 1200 kilometers per second! And you can’t call it a refreshing “breeze” - about 200 thousand degrees.
Can a person feel the solar wind?
Indeed, since the flow of hot particles is constantly rushing, why don't we feel how it "blows" us? Suppose the particles are so small that the skin does not feel their touch. But they are not noticed by terrestrial devices either. Why?
Because the Earth is protected from solar vortices by its magnetic field. The flow of particles flows around it, as it were, and rushes further. It is only on days when solar emissions are particularly strong that our magnetic shield has a hard time. A solar hurricane breaks through it and bursts into the upper atmosphere. Alien particles cause . The magnetic field is sharply deformed, forecasters talk about "magnetic storms." 
Because of them, space satellites go out of control. Planes disappear from the radar screens. Radio waves are interfered with and communications are disrupted. On such days, satellite dishes are turned off, flights are canceled, and “communication” with spacecraft is interrupted. In electrical networks, railway rails, pipelines, an electric current is suddenly born. From this, traffic lights switch by themselves, gas pipelines rust, and disconnected electrical appliances burn out. Plus, thousands of people feel discomfort and discomfort.
The cosmic effects of the solar wind can be detected not only during flares on the Sun: it is, albeit weaker, but blows constantly.
It has long been observed that the tail of a comet grows as it approaches the Sun. It causes the frozen gases that form the comet's nucleus to evaporate. And the solar wind carries these gases in the form of a plume, always directed in the opposite direction from the Sun. So the terrestrial wind turns the smoke from the chimney and gives it one form or another.
During years of increased activity, the Earth's exposure to galactic cosmic rays drops sharply. The solar wind is gaining such strength that it simply sweeps them to the outskirts of the planetary system.
There are planets in which the magnetic field is very weak, if not completely absent (for example, on Mars). Here nothing prevents the solar wind from roaming. Scientists believe that it was he who, over hundreds of millions of years, almost “blew out” its atmosphere from Mars. Because of this, the orange planet lost sweat and water and, possibly, living organisms.
Where does the solar wind subside?
Nobody knows the exact answer yet. Particles fly to the vicinity of the Earth, picking up speed. Then it gradually falls, but it seems that the wind reaches the farthest corners of the solar system. Somewhere there it weakens and is decelerated by rarefied interstellar matter.
So far, astronomers cannot say exactly how far this happens. To answer, you need to catch particles, flying farther and farther from the Sun, until they stop coming across. By the way, the limit where this will happen can be considered the boundary of the solar system. 
Traps for the solar wind are equipped with spacecraft that are periodically launched from our planet. In 2016, solar wind streams were captured on video. Who knows if he will not become the same familiar "character" of weather reports as our old friend - the earth's wind?
It can be used not only as a propeller for space sailboats, but also as a source of energy. The most famous application of the solar wind in this capacity was first proposed by Freeman Dyson, who suggested that a highly developed civilization could create a sphere around a star that would collect all the energy emitted by it. Proceeding from this, another method of searching for extraterrestrial civilizations was also proposed.
Meanwhile, a team of researchers at the University of Washington (Washington State University), led by Brooks Harrop (Brooks Harrop) proposed a more practical concept for using solar wind energy - Dyson-Harrop satellites. They are fairly simple power plants that collect electrons from the solar wind. A long metal rod pointed at the Sun is energized to generate a magnetic field that will attract electrons. At the other end is an electron trap receiver, consisting of a sail and a receiver.
According to Harrop's calculations, a satellite with a 300-meter rod, 1 cm thick and a 10-meter trap, in Earth's orbit will be able to "collect" up to 1.7 MW. This is enough to provide energy for about 1000 private houses. The same satellite, but with a one-kilometer rod and a sail of 8400 kilometers, will be able to “collect” already 1 billion billion gigawatts of energy (10 27 W). It remains only to transfer this energy to the Earth in order to abandon all its other forms.
Harrop's team proposes to transfer energy using a laser beam. However, if the design of the satellite itself is quite simple and quite feasible at the current level of technology, then the creation of a laser "cable" is still technically impossible. The fact is that in order to effectively collect the solar wind, the Dyson-Harrop satellite must lie outside the plane of the ecliptic, which means it is located millions of kilometers from the Earth. At such a distance, the laser beam will produce a spot thousands of kilometers in diameter. An adequate focusing system would require a lens between 10 and 100 meters in diameter. In addition, many dangers from possible system failures cannot be excluded. On the other hand, energy is also required in space itself, and small Dyson-Harrop satellites may well become its main source, replacing solar panels and nuclear reactors.
