The Sun is the closest star in our galaxy to us. The solar corona over the USA will tell about the “well-being” of a star. The passage of stars through the solar corona.

I'm not a fan of gravitational waves. Apparently, this is another one of the predictions of General Relativity.

The first prediction of general relativity about the curvature of space by a gravitational body was discovered in 1919 by the deflection of light rays from distant stars when light passed near the Sun.

But such a deviation of light rays is explained by the usual refraction of light rays in the transparent atmosphere of the Sun. And there is no need to bend space. The earth also sometimes “curves” space - mirages.

Gravitational waves are apparently from the same series of discoveries. But what prospects open up for humanity, even teleportation.

Einstein had already introduced an anti-gravity correction or lambda term into his theory, but then he changed his mind and recognized this lambda term as one of his biggest mistakes. And what prospects would open up with this antigravity. I put this lambda dick in my backpack and...

P.S. Geophysicists have long discovered gravitational waves. By making observations with gravimeters, we sometimes detect gravitational waves. A gravimeter in the same place suddenly shows an increase or decrease in gravity. These earthquakes excite "gravitational" waves. And there is no need to look for these waves in the distant Universe.

Reviews

Mikhail, I’m ashamed of you and of those who agree with you here. Half of them are bad at grammar, and probably even more so at physics.
And now - to the point. The squeals of your accomplices that when measuring gravitational waves, completely terrestrial influences will be detected, and not a gravitational signal at all, are unfounded. Firstly, the signal is searched at very specific frequencies; secondly, a very definite shape; thirdly, detection is carried out not by one interferometer, but by at least two, located hundreds of kilometers from each other, and only signals that simultaneously appear in both devices are taken into account. However, you can google the technology of this matter yourself. Or is it easier for you to sit and mutter without trying to understand?
Why did you suddenly start talking about some kind of teleportation in connection with gravitational waves? Who promised you teleportation? Einstein?
Let's move on. Let's talk about light refraction in the solar atmosphere.
The dependence of the refractive index of gases on temperature and pressure can be presented in the form n=1+AP/T (equation 3 in http://www.studfiles.ru/preview/711013/) Here P is pressure, T is temperature, A is constant. For hydrogen at a temperature of 300 K and a pressure of 1 atm. (i.e. 100 thousand pascals) the refractive index is 1.000132. This allows us to find the constant A:
AP/T =0.000132, A=0.000132*T/P=0.000132*293/100000 = 3.8*10^-6
In the chromosphere of the sun, the temperature reaches 20,000 degrees, and the gas concentration is 10^-12 g/cm3. – i.e. 10^-6 g/m3 Let's calculate the pressure using the Clapeyron-Mendeleev equation for a mole of gas: PV=RT. First, let's calculate the volume, assuming that the gas is hydrogen with a molar mass of 1 (since at this temperature the gas is completely atomic). The calculation is simple: 10^-6 g occupy the volume of 1 cubic meter, and 1 g – 10^6 cubic meters. From here we find the pressure: P=RT/V= 8.3*20000/10^6=0.166 Pa. Not thick at all!
Now we can calculate the refractive index of the solar chromosphere:
n=1+3.8*10^-6*0.166 /(2*10^4)=1+0.315*10^-10, i.e. the term after one is less than that of hydrogen under normal conditions by (1.32^-4/0.315*10^-10)=4.2*10^6 times. Four million times - and this is in the chromosphere!
The measurement of the deviation was carried out not in the chromosphere, adjacent to the very surface of the sun, its photosphere, but in its corona - but there the temperature is already millions of degrees, and the pressure is still hundreds of times less, i.e. the second term will decrease by at least four more orders of magnitude! No instrument can detect refraction in the corona of the Sun!
Use your head just a little bit.

"Are the distances between bodies measured in angular units? This is something new. Well, tell me how many angular units are between the earth and the moon, it will be very interesting. You lied, gentlemen. Continue to engage in mutual satisfaction in the same spirit. You are intellectual masturbators, and your fertility is the same as that of masturbators."

You're misinterpreting again! I told you that the sizes of celestial bodies and the distances between them in the sky are measured in angular units. Search for "Angular size of the Sun and Earth". Their size is approximately the same - 0.5 angular degrees, which is especially noticeable during total solar eclipses.
It’s just that the ram is a hundred times smarter than the learned ram.

The Sun is a huge sphere of hot gases that produce colossal energy and light and make life on Earth possible.

This celestial object is the largest and most massive in the Solar System. The distance from Earth to it is 150 million kilometers. It takes about eight minutes for heat and sunlight to reach us. This distance is also called eight light minutes.

The star that warms our earth consists of several outer layers, such as the photosphere, chromosphere and solar corona. The outer layers of the Sun's atmosphere create energy at the surface that bubbles up and escapes from the star's interior, and is detected as sunlight.

Components of the outer layer of the Sun

The layer we see is called the photosphere or sphere of light. The photosphere is marked by bright, boiling granules of plasma and darker, cooler ones that arise when the sun's magnetic fields break through the surface. Spots appear and move across the solar disk. Observing this movement, astronomers concluded that our star is turning around its axis. Since the Sun has no solid base, different regions rotate at different speeds. The equatorial regions complete a circle in about 24 days, while the polar rotation can take more than 30 days (to complete a revolution).

What is the photosphere?

The photosphere is also the source of flames that extend hundreds of thousands of miles above the surface of the Sun. Solar flares produce bursts of x-rays, ultraviolet radiation, electromagnetic radiation and radio waves. The source of X-ray and radio emission is the solar corona itself.

What is the chromosphere?

The zone surrounding the photosphere, which is the outer shell of the Sun, is called the chromosphere. A narrow region separates the corona from the chromosphere. Temperatures rise sharply in the transition region, from a few thousand degrees in the chromosphere to more than a million degrees in the corona. The chromosphere emits a reddish glow, as if from the combustion of superheated hydrogen. But the red rim can only be seen during an eclipse. At other times, the light from the chromosphere is usually too weak to be seen against the bright photosphere. The plasma density drops quickly and moves upward through the transition region from the chromosphere to the corona.

What is the solar corona? Description

Astronomers are tirelessly researching the mystery that lies within the solar corona. What is she like?

This is the Sun's atmosphere or outer layer. This name was given because its appearance becomes obvious when a total solar eclipse occurs. Particles from the corona extend far into space and, in fact, reach the Earth's orbit. The shape is mainly determined by the magnetic field. Free electrons in corona motion along form many different structures. The shapes seen in the corona above sunspots are often horseshoe-shaped, further confirming that they follow magnetic field lines. From the top of such "arches" long stretch marks can extend out to a distance the diameter of the Sun or more, as if some process is pulling material from the top of the arches into space. This involves the solar wind blowing outward through our solar system. Astronomers have called these phenomena "serpentine helmets" because of their resemblance to the scalloped helmets worn by knights and used by some German soldiers before 1918.

What is the crown made of?

The material from which the solar corona is formed is extremely hot, consisting of tenuous plasma. The temperature inside the corona is over a million degrees, surprisingly much higher than the temperature on the surface of the Sun, which is about 5500 °C. The pressure and density of the corona are much lower than in the Earth's atmosphere.

By observing the visible spectrum of the solar corona, bright emission lines were discovered at wavelengths that do not correspond to known materials. In this regard, astronomers have proposed the existence of "coronium" as the main gas in the corona. The true nature of this phenomenon remained a mystery until it was discovered that the coronal gases were superheated above 1,000,000 °C. In the presence of such high temperatures, the two dominant elements - hydrogen and helium - are completely stripped of their electrons. Even minor substances such as carbon, nitrogen and oxygen were stripped down to bare nuclei. Only the heavier constituents (iron and calcium) are able to retain some of their electrons when exposed to such temperatures. The emission from these highly ionized elements, which form the spectral lines, remained mysterious to early astronomers until recently.

Brightness and interesting facts

The solar surface is too bright and, as a rule, its solar atmosphere is inaccessible to our vision; the corona of the Sun is also not visible to the naked eye. The outer layer of the atmosphere is very thin and weak, so it can only be seen from Earth during a solar eclipse or using a special corona telescope that simulates an eclipse by covering the bright solar disk. Some coronagraphs use ground-based telescopes, others are carried out on satellites.

Occurs due to its enormous temperature. On the other hand, the solar photosphere emits very little X-rays. This allows us to view the corona across the solar disk as we observe it in X-rays. For this, special optics are used that allow you to see X-rays. In the early 70s, the first US space station, Skylab, used an X-ray telescope, with which the solar corona and sunspots or holes were clearly visible for the first time. Over the past decade, a wealth of information and images of the Sun's corona have been provided. With the help of satellites, the solar corona becomes more accessible for new and interesting observations of the Sun, its features and dynamic nature.

Sun temperature

Although the internal structure of the solar core is hidden from direct observation, it can be concluded, using various models, that the maximum temperature inside our star is about 16 million degrees (Celsius). The photosphere - the visible surface of the Sun - has a temperature of about 6000 degrees Celsius, but it increases very sharply from 6000 degrees to several million degrees in the corona, in the region of 500 kilometers above the photosphere.

The sun is hotter on the inside than on the outside. However, the Sun's outer atmosphere, the corona, is actually hotter than the photosphere.

In the late thirties, Grotrian (1939) and Edlen discovered that the strange spectral lines observed in the spectrum of the solar corona were emitted by elements such as iron (Fe), calcium (Ca) and nickel (Ni) in very high stages of ionization. They concluded that the coronal gas is highly heated, with temperatures exceeding 1 million degrees.

The question of why the solar corona is so hot remains one of the most fascinating puzzles in astronomy of the last 60 years. There is no clear answer to this question yet.

Although the solar corona is disproportionately hot, it is also very low in density. Thus, only a small fraction of the total solar radiation is required to recharge the corona. The total power emitted in X-rays is only about one millionth the total luminosity of the Sun. An important question is how energy is transported to the corona and what mechanism is responsible for the transport.

Power Mechanisms of the Solar Corona

Over the years, several different mechanisms for feeding the crown have been proposed:

Acoustic waves.

Fast and slow magneto-acoustic waves of bodies.

Alfvénic wave bodies.

Slow and fast magneto-acoustic surface waves.

Current (or magnetic field) - dissipation.

Flows of particles and magnetic flux.

These mechanisms have been tested both theoretically and experimentally and to date only acoustic waves have been excluded.

It has not yet been studied where the upper limit of the crown ends. The Earth and other planets of the solar system are located inside the corona. The optical radiation of the corona is observed at 10-20 solar radii (tens of millions of kilometers) and is combined with the phenomenon of zodiacal light.

Magnetic carpet of the solar crown

Recently, the "magnetic carpet" has been associated with the coronal heating puzzle.

Observations with high spatial resolution show that the surface of the Sun is covered with weak magnetic fields concentrated in small areas of opposite polarity (carpet magnet). These magnetic concentrations are believed to be the main points of individual flux tubes carrying electric current.

Recent observations of this “magnetic carpet” show interesting dynamics: photospheric magnetic fields are constantly moving, interacting with each other, dissipating and emerging for a very short period of time. Magnetic reconnection between opposite polarities can change the field topology and release magnetic energy. The reconnection process will also dissipate electrical currents that convert electrical energy into heat.

This is a general idea of ​​how a magnetic carpet may be involved in coronal heating. However, it is impossible to say that the “magnetic carpet” ultimately solves the problem of corona heating, since a quantitative model of the process has not yet been proposed.

Can the Sun go out?

The solar system is so complex and unknown that sensational statements such as: “The Sun will soon go out” or, conversely, “The temperature of the Sun is rising and soon life on Earth will become impossible” sound at least ridiculous. Who can make such predictions without knowing exactly what mechanisms underlie this mysterious star?!

A small comet created a big sensation: it was able to pass through the corona of the Sun, where the temperature is millions of degrees. True, she lost her tail, but it will soon “grow back,” scientists assure.

Almost every one of us has seen a comet once in our lives. These small celestial bodies are significantly different in appearance from the usual population of our sky: unlike stars and planets, comets look blurry, and the head of the comet is followed by an even more blurry trail - the tail. We see comets as they approach the Sun, where, under the influence of the solar wind, a coma is transformed into a trail - a foggy shell around the comet. Comets, like planets, revolve around the Sun, but their orbits are very elongated. As a result, some comets are visible from Earth only once every few thousand years. The Kreutz family comets are a special case. This is a group of “sun-scratching” comets - they were first described at the end of the 19th century by the German astronomer Heinrich Kreutz. According to modern ideas, these objects are the remains of a giant comet that collapsed about two thousand years ago. Every day, several of these comets fly near the Sun and disintegrate: most of them are small and inconspicuous. However, scientists assumed that larger, noticeable comets could not survive passage through the solar corona, where the temperature is millions of degrees: a small celestial body would simply evaporate. But recent observations have cast doubt on this hypothesis.. On Friday, Comet Lovejoy of the Kreutz family passed unscathed through the solar corona, although it lost its tail.

“This comet has two features. The first is that usually circumsolar comets of the Kreutz family open from satellite (SOHO), since they are very small and become visible only near the Sun. And this one was discovered from Earth by an Australian amateur,” Vladimir Surdin, a senior researcher at the SAI of Moscow State University, explained to Gazeta.Ru. - The second feature is that everyone thought that the comet would die when approaching the Sun, but it survived. True, she lost her tail. As far as I understand,she passed through the inner crown, the tail remained there. It should grow back in a couple of days.

But that’s just my guess.” "Comets can pose a serious threat"

The comet passed 140 thousand km from the surface of the Sun at about 4.00 Moscow time Friday. This is a very close distance: Mercury is more than 100 times farther from the Sun, even the Moon is 2.5 times farther from Earth. Before the “collision” with the Sun, the SOHO space observatory recorded how the comet, whose brightness had reached minus the fourth magnitude (the brightness of Venus), went beyond the disk of the luminary. Scientists believed that they had said goodbye to the comet forever. The likelihood of her “survival” was extremely low. However, then the orbiting solar telescope SDO recorded a foggy cloud appearing from behind the horizon of the star - the comet itself or its remnants. “Somehow she survived being in the solar corona, heated to several million degrees! Its return has already been recorded by the LASCO and SECCHI coronagraphs, and it is almost as bright as before. True, it lost its tail, which is still visible in the region of space where the comet disappeared from us,” explains Carl Battams, a solar researcher from Washington, whose words are quoted by space.com .

Australian amateur astronomer Terry Lovejoy, who discovered the comet on November 27 this year, is very happy to have been able to contribute to astronomy.

“The attention to the comet I discovered is wonderful. Not only scientists are interested: there are a lot of links all over Facebook, although I don’t use it. It seems to me that people liked the name of the comet (Lovejoy in English: love means “love”, and joy =- “joy” =- approx. "Gazeta.Ru"),” he noted. For scientists, the work has just begun: they will have to observe the comet in detail using various telescopes in order to understand how it managed to survive such a close encounter with the Sun

The Sun is the only star in the Solar System; all the planets of the system, as well as their satellites and other objects, including cosmic dust, move around it. If we compare the mass of the Sun with the mass of the entire solar system, it will be about 99.866 percent.

The Sun is one of the 100,000,000,000 stars in our Galaxy and is the fourth largest among them. The closest star to the Sun, Proxima Centauri, is located four light years from Earth. The distance from the Sun to planet Earth is 149.6 million km; light from a star reaches in eight minutes. The star is located at a distance of 26 thousand light years from the center of the Milky Way, while it rotates around it at a speed of 1 revolution every 200 million years.

Presentation: Sun

According to the spectral classification, the star is a “yellow dwarf” type; according to rough calculations, its age is just over 4.5 billion years, it is in the middle of its life cycle.

The sun, consisting of 92% hydrogen and 7% helium, has a very complex structure. At its center there is a core with a radius of approximately 150,000-175,000 km, which is up to 25% of the total radius of the star; at its center the temperature approaches 14,000,000 K.

The core rotates around its axis at high speed, and this speed significantly exceeds the outer shells of the star. Here, the reaction of helium formation from four protons occurs, resulting in a large amount of energy passing through all layers and emitted from the photosphere in the form of kinetic energy and light. Above the core there is a zone of radiative transfer, where temperatures are in the range of 2-7 million K. This is followed by a convective zone approximately 200,000 km thick, where there is no longer re-radiation for energy transfer, but plasma mixing. At the surface of the layer the temperature is approximately 5800 K.

The atmosphere of the Sun consists of the photosphere, which forms the visible surface of the star, the chromosphere, which is about 2000 km thick, and the corona, the last outer shell of the sun, the temperature of which is in the range of 1,000,000-20,000,000 K. From the outer part of the corona, ionized particles called the solar wind emerge. .

When the Sun reaches an age of approximately 7.5 - 8 billion years (that is, in 4-5 billion years), the star will turn into a “red giant”, its outer shells will expand and reach the Earth’s orbit, possibly pushing the planet further away.

Under the influence of high temperatures, life as we understand it today will simply become impossible. The Sun will spend the final cycle of its life in the “white dwarf” state.

The sun is the source of life on Earth

The sun is the most important source of heat and energy, thanks to which, with the assistance of other favorable factors, there is life on Earth. Our planet Earth rotates around its axis, so every day, being on the sunny side of the planet, we can watch the dawn and the amazingly beautiful phenomenon of sunset, and at night, when part of the planet falls into the shadow side, we can watch the stars in the night sky.

The sun has a huge impact on the life of the Earth, it participates in photosynthesis and helps in the formation of vitamin D in the human body. The solar wind causes geomagnetic storms and it is its penetration into the layers of the earth's atmosphere that causes such a beautiful natural phenomenon as the northern lights, also called the polar lights. Solar activity changes towards decreasing or increasing approximately every 11 years.

Since the beginning of the space age, researchers have been interested in the Sun. For professional observation, special telescopes with two mirrors are used, international programs have been developed, but the most accurate data can be obtained outside the layers of the Earth’s atmosphere, so most often research is carried out from satellites and spacecraft. The first such studies were carried out back in 1957 in several spectral ranges.

Today, satellites are launched into orbit, which are observatories in miniature, making it possible to obtain very interesting materials for studying the star. Even during the years of the first human space exploration, several spacecraft were developed and launched aimed at studying the Sun. The first of these were a series of American satellites, launched in 1962. In 1976, the West German Helios-2 spacecraft was launched, which for the first time in history approached the star at a minimum distance of 0.29 AU. At the same time, the appearance of light helium nuclei during solar flares, as well as magnetic shock waves covering the range of 100 Hz-2.2 kHz, were recorded.

Another interesting device is the Ulysses solar probe, launched in 1990. It is launched into a near-solar orbit and moves perpendicular to the ecliptic strip. 8 years after launch, the device completed its first orbit around the Sun. He recorded the spiral shape of the luminary's magnetic field, as well as its constant increase.

In 2018, NASA plans to launch the Solar Probe+ apparatus, which will approach the Sun at the closest possible distance - 6 million km (this is 7 times less than the distance reached by Helius-2) and will occupy a circular orbit. To protect against extreme temperatures, it is equipped with a carbon fiber shield.

New technology for observing exoplanets has been created

Optical technology for “correcting” light from distant stars was developed by physicists from MIPT and IKI RAS. It will significantly improve the “vision” of telescopes and directly observe exoplanets comparable in size to the Earth. The work was published in the Journal of Astronomical Telescopes, Instruments, and Systems. “MK” talked about the development with the head of the scientific group, associate professor at MIPT and head of the Laboratory of Planetary Astronomy at the Institute of Space Research of the Russian Academy of Sciences, Alexander TAVROV.

The first exoplanets - planets outside the solar system - were discovered at the end of the 20th century, and now more than two thousand of them are known. It is almost impossible to see their own light without special instruments - it is “eclipsed” by the radiation of stars. Therefore, until recently, exoplanets were found only by indirect methods: by recording weak periodic fluctuations in the luminosity of a star when a planet passes in front of its disk (transit method), or fluctuations of the star itself under the influence of the planet’s gravity (radial velocity method). It wasn't until the late 2000s that astronomers were able to directly image exoplanets for the first time. For such surveys, coronagraphs are used, first created in the 1930s to observe the solar corona outside of eclipses. Inside, these devices have an “artificial moon” that screens part of the field of view, for example, covering the solar disk, allowing you to see the dim solar corona.

In order to repeat the method with distant objects - stars and exoplanets orbiting their luminaries outside the solar system, a significantly higher level of accuracy and significantly higher resolution of the telescope itself on which the coronagraph is installed is required.

If we observe a celestial object from Earth using a telescope, then without special adaptive optics we are unlikely to achieve a good result. Light passes through a turbulent atmosphere, which makes it difficult to ultimately see the object in good quality, explains Alexander Tavrov. - Space telescopes are used to observe exoplanets. The earth’s atmosphere no longer interferes with them, but there are many other factors that also require the presence of adaptive optics in the telescope (as a rule, this is some kind of special membrane - a controlled curved mirror that allows you to “even out” light from distant objects). Western colleagues have such accurate, expensive optics, but we, alas, do not have them yet. Our know-how lies in an innovative solution that makes it possible to do without super-precise adaptive mirrors when observing exoplanets. On the path of light to the coronagraph, we placed another optical device - an unbalanced interferometer. To put it simply, it corrects the image obtained from the star and the exoplanet orbiting around it, after which on the coronagraph we can clearly distinguish the glow of an individual planet from the light of the star. The quality of the image obtained in this way is no worse than that of Western colleagues, and in some ways even better.