What is the sun as a celestial object. Types of celestial bodies - abstract

The universe consists of a huge number of cosmic bodies. Every night we can contemplate the stars in the sky, which seem very small, although they are not. In fact, some of them are many times larger than the Sun. It is assumed that a planetary system is formed around each lone star. So, for example, the solar system was formed near the Sun, consisting of eight large, as well as small and comets, black holes, cosmic dust, etc.

The Earth is a cosmic body because it is a planet, a spherical object that reflects sunlight. Seven other planets are also visible to us only due to the fact that they reflect the light of the star. In addition to Mercury, Venus, Mars, Uranus, Neptune and Pluto, which was also considered a planet until 2006, a huge number of asteroids, which are also called minor planets, are also concentrated in the solar system. Their number reaches 400 thousand, but many scientists agree that there are more than a billion of them.

Comets are also cosmic bodies moving along elongated trajectories and approaching the Sun at a certain time. They consist of gas, plasma and dust; overgrown with ice, reach a size of tens of kilometers. When approaching a star, comets gradually melt. From high temperature, the ice evaporates, forming a head and tail, reaching amazing sizes.

Asteroids are the cosmic bodies of the solar system, also called minor planets. Their main part is concentrated between Mars and Jupiter. They consist of iron and stone and are divided into two types: light and dark. The first ones are lighter, the second ones are harder. Asteroids are irregular in shape. It is assumed that they were formed from the remnants of cosmic matter after the formation of the main planets, or they are fragments of a planet located between Mars and Jupiter.

Some cosmic bodies reach the Earth, but, passing through the thick layers of the atmosphere, they heat up during friction and break into small pieces. Therefore, relatively small meteorites fell on our planet. This phenomenon is by no means uncommon; fragments of asteroids are kept in many museums around the world, they were found in 3500 places.

There are not only large objects in space, but also tiny ones. So, for example, bodies up to 10 m in size are called meteoroids. Cosmic dust is even smaller, up to 100 microns in size. It appears in the atmospheres of stars as a result of gas emissions or explosions. Not all space bodies have been studied by scientists. These include black holes, which are found in almost every galaxy. They cannot be seen, it is only possible to determine their location. Black holes have a very strong attraction, so they do not even let go of light. They annually absorb huge volumes of hot gas.

Space bodies have different shapes, sizes, location in relation to the Sun. Some of them are combined into separate groups to make it easier to classify them. So, for example, asteroids located between the Kuiper belt and Jupiter are called Centaurs. Vulcanoids are thought to lie between the Sun and Mercury, although no object has yet been discovered.

Last year I gave my husband binoculars. This, of course, is not a telescope, but at maximum magnification you can see the Moon a little, especially on a full moon. Somewhere out there, very far from us, there are so many interesting and unknown things. I will tell you a little about this now.

Celestial bodies and their types

In some popular science program on the topic of space, the phrase "celestial body" is sure to occur. It is understood as an object of a miraculous nature, which is located in outer space, well, or came from there. Sometimes such bodies are called astronomical objects. The essence of this does not change. The list of celestial bodies includes:

comets;
planets;
meteorites;
asteroids;
stars.

All of them have a lot of differences from each other. First of all, each astronomical object has its own size. The largest are stars, and the smallest are meteorites. Various celestial bodies can form their own systems. For example, a star system is made up of planets. Asteroids, having united among themselves, form belts, and stars - galaxies. Only comets, as a rule, are single celestial bodies.

Comets are classified as small celestial bodies. They move around the Sun in an elongated orbit. Comets are made up of:

ammonia;
methane;
other components.

The main part of a comet is the nucleus. It is it that almost 100% makes up the mass of this celestial body. From Earth, the comet looks like a luminous ball with a tail. It appears only when the celestial body approaches the Sun. At this time, various dust and gas particles fly out of the comet's nucleus, which complete the comet's tail. The greater the distance from the comet to the Sun, the brighter it becomes. And all due to the fact that the ice, which is also part of the comet, under the influence of the Sun turns into gases. It is their accumulation that gives such a bright glow to the celestial body.

Scientists claim that comets are within the solar system. Several such astronomical objects are recorded every year. In total, more than 3,000 comets have already been discovered.

Parshakov Evgeny Afanasyevich

At first glance, all the celestial bodies of the solar system have very different characteristics. However, all of them can be divided into three large groups according to their composition. One group includes the densest bodies of the solar system, with a density of about 3 g/cm3 or more. These include primarily the terrestrial planets: Mercury, Venus, Earth and Mars. The same group of celestial bodies includes some large satellites of the planets: the Moon, Io, Europa and, apparently, Triton, as well as a number of small satellites located near their planet - Phobos, Deimos, Amalthea, etc.

The fact that the densest bodies in the solar system include celestial bodies that are close to the central body around which they revolve is far from accidental. In addition to the fact that the terrestrial planets are located near the Sun, which heats their surface and thereby contributes to the dissipation from the surface and atmosphere of celestial bodies of not only the gas, but also the ice component, in addition to this, the dissipation of light matter is also facilitated by the transfer of mechanical energy through the mechanism of tidal friction into thermal energy. The tidal friction caused in the body of celestial bodies by the central body is the stronger, the closer they are to it. This partly explains the fact that the nearby satellites of Jupiter, Io and Europa, have a density of 3.5 and 3.1 g/cm3, respectively, while the more distant, although more massive, satellites of Ganymede and Callisto have a much lower density, respectively 1.9 and 1.8g/cm3. This also explains the fact that all close satellites of the planets revolve around their planets synchronously, i.e. always turned to them by one side, so that their periods of axial rotation are equal to the periods of orbital revolution. However, tidal friction, which contributes to the heating of the interiors of celestial bodies and an increase in their density, is caused not only by the central bodies of their satellites, but also by satellites of the central bodies, as well as by some celestial bodies of others belonging to the same class: satellites of others, most of all from relatives, satellites, planets from other planets.

Celestial bodies with a high density can be called silicate celestial bodies, meaning that the main component in them is the silicate component (stone-metal rocks), which consists of the heaviest and most refractory substances: silicon, calcium, iron, aluminum, magnesium, sulfur and many other elements and their compounds, including mainly with oxygen. Along with the silicate component, many celestial bodies of this group contain icy (water ice, water, carbon dioxide, nitrogen, oxygen) and very little gas (hydrogen, helium) components. But their share in the total composition of the substance is insignificant. The silicate component is, as a rule, over 99% of the substance.

The group of silicate celestial bodies of the solar system includes not only four planets and a dozen satellites of the planets, but a large number of asteroids circulating in the asteroid belt between the orbits of Mars and Jupiter. The number of asteroids, the largest of which are Ceres, Pallas, Vesta, Hygiea, etc., is in the tens of thousands (according to some sources, hundreds of thousands and even millions).

Another group of celestial bodies includes icy bodies, the main component of which is the ice component, this is the most numerous group of celestial bodies in the solar system. It includes the only known planet Pluto and many yet undiscovered transplutonian planets, large satellites of the planets: Ganymede, Callisto, Titan, Charon, and also, apparently, two or three dozen other satellites. This group also includes all comets, the number of which in the solar system is estimated in many millions, and perhaps even billions.

This group of celestial bodies is the main group of celestial bodies in the solar system and, apparently, in the entire galaxy. Behind Pluto, according to many researchers, there are more planets. No doubt they are right. Icy celestial bodies are the most numerous and main group of celestial bodies in the solar system, as, of course, in all other star-planetary systems, from the smallest to the largest.

The icy bodies of the solar system consist mainly of the icy component: water ice, carbon dioxide, nitrogen, oxygen, ammonia, methane, etc., which occupies the main part of their substance in icy bodies. The remaining, insignificant part of the ice bodies is mainly the silicate component. The specific gravity of the gas component in icy celestial bodies, as well as in silicate ones, is extremely insignificant, which is explained by their relatively small mass, as a result of which they cannot retain light gases near their surface for a long time - hydrogen and helium, which are dispersed in interplanetary space, for with the exception, perhaps, of planets far from the Sun, on the surface of which the temperature is very low.

Small icy celestial bodies - comets are located not only on the periphery of the solar system, beyond Pluto. A large number of comets are apparently also located between the orbits of the giant planets.

The third, smallest, but most massive group of bodies in the solar system is celestial bodies, which include all three components in large numbers: ice, silicate and gas. This group includes only five celestial bodies of the solar system: the Sun, Jupiter, Saturn, Uranus and Neptune. In all these bodies there is a lot of hydrogen and helium, but their proportion in these bodies is different. During the formation of gas bodies, if they are called that, they, having at the first stage of their development a mass of less than 10 Earth masses, could not hold light gases around them - hydrogen and helium, and were formed at first as ice bodies. And their composition at this stage included ice and silicate components. A significant part of the gas component, which was acquired by gaseous celestial bodies during galactic winters, was transformed through chemical reactions into an ice component. So hydrogen and oxygen, entering into a chemical reaction, give rise to water and water ice. Methane and some other substances of the ice component arose from the gas component. As a result, the share of the ice component during the accretion of diffuse matter on the surface of celestial bodies increased, while the share of the gas component decreased.

Giant planets, unlike other celestial bodies, have a fast axial rotation and an extended hydrogen-helium atmosphere. As a result, in their equatorial part, it is possible that light gases leak into interplanetary space from the upper layers of the atmosphere due to a large centrifugal force. For example, on Saturn the upper layers of the cloud layer revolve around the center of the planet at a linear speed of about 10 km/sec, while on the Earth it is only about 0.5 km/sec. It can be assumed that earlier, during galactic winters, the giant planets had much more powerful and extended atmospheres, but then, after the end of the next galactic winter, they partially lost them. If the icy and silicate celestial bodies lose their gas component due to their small mass, then the gas planets, especially Jupiter, lose it due to their rapid rotation.

> Deep Sky Objects

Explore objects of the universe with photo: stars, nebulae, exoplanets, star clusters, galaxies, pulsars, quasars, black holes, dark matter and energy.

For many centuries, millions of human eyes, with the onset of night, direct their gaze up - towards the mysterious lights in the sky - stars in our universe. Ancient people saw various figures of animals and people in clusters of stars, and for each of them they created their own story.

exoplanets are planets outside the solar system. Since the first exoplanet discovery in 1992, astronomers have discovered more than 1,000 such planets in planetary systems around the Milky Way galaxy. Researchers believe they will find many more exoplanets.

Word " nebula comes from the Latin word for "clouds". In fact, a nebula is a cosmic cloud of gas and dust floating in space. More than one nebula are called nebulae. Nebulae are the basic building blocks of the universe.

Some stars are part of a whole group of stars. Most of them are binary systems, where two stars revolve around their common center of mass. Some are part of a triple star system. And some of the stars are at the same time part of a larger group of stars, which is called " star cluster».

Galaxies - large groupings of stars, dust, gas, held together by gravity. They can vary greatly in size and shape. Most objects in space are parts of a galaxy. These are stars with planets and satellites, asteroids, black holes and neutron stars, nebulae.

Pulsars considered one of the strangest objects in the entire universe. In 1967, at the Cambridge Observatory, Jocelyn Bell and Anthony Hewish were studying the stars and found something quite extraordinary. It was an object very similar to a star, which, as it were, emitted fast pulses of radio waves. The existence of radio sources in space has been known for quite some time.

Quasars are the most distant and brightest objects in the known universe. In the early 1960s, scientists identified quasars as radio stars because they could be detected using a strong source of radio waves. In fact, the term quasar comes from the words "quasi-stellar radio source". Today, many astronomers refer to them as QSOs in their writings.

Black holes, undoubtedly the strangest and most mysterious objects in space. Their bizarre properties are able to defy the laws of the physics of the universe and even the nature of existing reality. To understand what black holes are, we must learn to think outside the box and use a little imagination.

Dark matter and dark energy- this is what is not visible to the eye, but their presence has been proven in the course of observations of Universe. Billions of years ago, our universe was born after a catastrophic Big Bang. As the early universe slowly cooled, life began to develop in it. As a result, stars, galaxies and other visible parts of it were formed.

Most of us are familiar with the stars, planets and moons. But besides these well-known celestial bodies, there are many other amazing sights. There are colorful nebulae, thin star clusters and massive galaxies. Add to that the mysterious pulsars and quasars, black holes that devour all matter that comes too close. And now try to identify the invisible substance known as dark matter. Click on any image above to learn more about it, or use the menu above to navigate your way through the sky.

Watch the video about the Universe to better understand the nature of fast radio bursts and the characteristics of interstellar dust.

fast radio bursts

Astrophysicist Sergei Popov about rotating radio transients, the SKA telescope system and microwave ovens at the observatory:

interstellar dust

Astronomer Dmitry Wiebe on interstellar reddening of light, modern models of cosmic dust and its sources:

Our Universe contains an amazing variety of cosmic objects, which are called celestial bodies or astronomical objects. However, it is worth noting that much of the visible deep space consists of empty space - a cold and dark void inhabited by a number of celestial bodies that range from the commonplace to the strange. Known to astronomers as celestial objects, celestial bodies, astronomical objects and astronomical bodies, they are the material that fills the empty space of the universe. In our list of deep space celestial bodies, you can get acquainted with various objects (stars, exoplanets, nebulae, clusters, galaxies, pulsars, black holes, quasars), as well as get photos of these celestial bodies and the surrounding space, models and diagrams with a detailed description and characteristics of the parameters.

To find out if there are celestial bodies that glow themselves, you first need to understand what celestial bodies the solar system consists of. The solar system is a planetary system, in the center of which is a star - the Sun, and around it are 8 planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. In order for a celestial body to be called a planet, it must meet the following requirements
Make rotational movements around the star.
To have a shape in the form of a sphere, due to sufficient gravity.
Do not have other large bodies around its orbit.
Don't be a star.

The planets do not emit light, they can only reflect the rays of the Sun that hit them. Therefore, it cannot be said that the planets are celestial bodies that glow on their own. Stars are such celestial bodies. The sun is the source of light on Earth The celestial bodies that glow themselves are the stars. The closest star to Earth is the Sun. Thanks to its light and warmth, all living things can exist and develop. The sun is the center around which the planets, their satellites, asteroids, comets, meteorites and cosmic dust revolve.

The sun appears to be a solid spherical object, because when you look at it, its contours look quite distinct. However, it does not have a solid structure and consists of gases, the main among which is hydrogen, and other elements are also present.

To see that the Sun does not have clear contours, you need to look at it during an eclipse. Then you can see that it is surrounded by a driving atmosphere, which is several times larger than its diameter. With normal glare, this halo is not visible because of the bright light. Thus, the Sun has no exact boundaries and is in a gaseous state. Stars The number of existing stars is unknown, they are located at a great distance from the Earth and are visible as small dots. Stars are celestial bodies that glow on their own. What does this mean? Stars are hot balls of gas in which thermonuclear reactions take place. Their surfaces have different temperatures and densities. The size of the stars also differ from each other, while they are larger and more massive than the planets. There are stars that are larger than the Sun, and vice versa.

A star is made up of gas, mostly hydrogen. On its surface, from high temperature, the hydrogen molecule breaks up into two atoms. An atom is made up of a proton and an electron. However, under the influence of high temperatures, atoms "release" their electrons, resulting in a gas called plasma. An atom without an electron is called a nucleus. How stars emit light A star, due to the gravitational force, tries to compress itself, as a result of which the temperature in its central part rises strongly. Nuclear reactions begin to occur, as a result, helium is formed with a new nucleus, which consists of two protons and two neutrons. As a result of the formation of a new nucleus, a large amount of energy is released. Particles-photons are emitted as an excess of energy - they also carry light. This light exerts a strong pressure that emanates from the center of the star, resulting in an equilibrium between the pressure emanating from the center and the gravitational force.

Thus, the celestial bodies that glow themselves, namely the stars, glow due to the release of energy during nuclear reactions. This energy is used to contain gravitational forces and to emit light. The more massive the star, the more energy is released and the brighter the star shines. Comets A comet consists of an ice clot in which gases and dust are present. Its core does not emit light, however, when approaching the Sun, the core begins to melt and particles of dust, dirt, gases are thrown into outer space. They form a kind of foggy cloud around the comet, which is called a coma.

It cannot be said that a comet is a celestial body that itself glows. The main light it emits is reflected sunlight. Being far from the Sun, the light of the comet is not visible, and only approaching and receiving the sun's rays, it becomes visible. The comet itself emits a small amount of light, due to the atoms and molecules of the coma, which release the quanta of sunlight they receive. The "tail" of a comet is "scattering dust", which is illuminated by the Sun. Meteorites Under the influence of gravity, solid cosmic bodies called meteorites can fall to the surface of the planet. They do not burn up in the atmosphere, but when passing through it, they become very hot and begin to emit a bright light. Such a luminous meteorite is called a meteor. Under the pressure of air, a meteor can break into many small pieces. Although it gets very hot, the inside of it usually remains cold, because in such a short time that it falls, it does not have time to heat up completely. It can be concluded that the celestial bodies that glow themselves are stars. Only they are capable of emitting light due to their structure and the processes occurring inside. Conventionally, we can say that a meteorite is a celestial body that itself glows, but this becomes possible only when it enters the atmosphere.