Universe (space)- this is the whole world around us, boundless in time and space and infinitely diverse in the forms that eternally moving matter takes. The boundlessness of the Universe can be partly imagined on a clear night with billions of different sizes of luminous flickering points in the sky, representing distant worlds. Rays of light at a speed of 300,000 km / s from the most distant parts of the universe reach the Earth in about 10 billion years.
According to scientists, the universe was formed as a result of the "Big Bang" 17 billion years ago.
It consists of clusters of stars, planets, cosmic dust and other cosmic bodies. These bodies form systems: planets with satellites (for example, the solar system), galaxies, metagalaxies (clusters of galaxies).
Galaxy(Late Greek galaktikos- milky, milky, from Greek gala- milk) is an extensive star system that consists of many stars, star clusters and associations, gas and dust nebulae, as well as individual atoms and particles scattered in interstellar space.
There are many galaxies in the universe of various sizes and shapes.
All stars visible from Earth are part of the Milky Way galaxy. It got its name due to the fact that most of the stars can be seen on a clear night in the form of the Milky Way - a whitish blurry band.
In total, the Milky Way Galaxy contains about 100 billion stars.
Our galaxy is in constant rotation. Its speed in the universe is 1.5 million km/h. If you look at our galaxy from its north pole, then the rotation occurs clockwise. The sun and the stars closest to it make a complete revolution around the center of the galaxy in 200 million years. This period is considered galactic year.
Similar in size and shape to the Milky Way galaxy is the Andromeda Galaxy, or the Andromeda Nebula, which is located at a distance of about 2 million light years from our galaxy. Light year- the distance traveled by light in a year, approximately equal to 10 13 km (the speed of light is 300,000 km / s).
To illustrate the study of the movement and location of stars, planets and other celestial bodies, the concept of the celestial sphere is used.
Rice. 1. The main lines of the celestial sphere
Celestial sphere is an imaginary sphere of arbitrarily large radius, in the center of which is the observer. Stars, the Sun, the Moon, planets are projected onto the celestial sphere.
The most important lines on the celestial sphere are: a plumb line, zenith, nadir, celestial equator, ecliptic, celestial meridian, etc. (Fig. 1).
plumb line- a straight line passing through the center of the celestial sphere and coinciding with the direction of the plumb line at the point of observation. For an observer on the surface of the Earth, the plumb line passes through the center of the Earth and the point of observation.
The plumb line intersects with the surface of the celestial sphere at two points - zenith, over the observer's head, and nadire - diametrically opposite point.
The great circle of the celestial sphere, the plane of which is perpendicular to the plumb line, is called mathematical horizon. It divides the surface of the celestial sphere into two halves: visible to the observer, with the apex at the zenith, and invisible, with the apex at the nadir.
The diameter around which the celestial sphere rotates is axis of the world. It intersects with the surface of the celestial sphere at two points - north pole of the world and south pole of the world. The North Pole is the one from which the rotation of the celestial sphere occurs clockwise, if you look at the sphere from the outside.
The great circle of the celestial sphere, whose plane is perpendicular to the axis of the world, is called celestial equator. It divides the surface of the celestial sphere into two hemispheres: northern, with a peak at the north celestial pole, and south, with a peak at the south celestial pole.
The great circle of the celestial sphere, the plane of which passes through the plumb line and the axis of the world, is the celestial meridian. It divides the surface of the celestial sphere into two hemispheres - eastern and western.
The line of intersection of the plane of the celestial meridian and the plane of the mathematical horizon - noon line.
Ecliptic(from Greek. ekieipsis- Eclipse) - a large circle of the celestial sphere, along which the apparent annual movement of the Sun, or rather, its center, occurs.
The plane of the ecliptic is inclined to the plane of the celestial equator at an angle of 23°26"21".
To make it easier to remember the location of the stars in the sky, people in antiquity came up with the idea of combining the brightest of them into constellations.
Currently, 88 constellations are known that bear the names of mythical characters (Hercules, Pegasus, etc.), zodiac signs (Taurus, Pisces, Cancer, etc.), objects (Libra, Lyra, etc.) (Fig. 2).
Rice. 2. Summer-autumn constellations
Origin of galaxies. The solar system and its individual planets still remains an unsolved mystery of nature. There are several hypotheses. It is currently believed that our galaxy formed from a gas cloud composed of hydrogen. At the initial stage of the evolution of the galaxy, the first stars formed from the interstellar gas-dust medium, and 4.6 billion years ago, the solar system.
Composition of the solar system
The set of celestial bodies moving around the Sun as a central body forms solar system. It is located almost on the outskirts of the Milky Way galaxy. The solar system is involved in rotation around the center of the galaxy. The speed of its movement is about 220 km / s. This movement occurs in the direction of the constellation Cygnus.
The composition of the solar system can be represented in the form of a simplified diagram shown in fig. 3.
Over 99.9% of the mass of the matter of the solar system falls on the Sun and only 0.1% - on all its other elements.
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Hypothesis of I. Kant (1775) - P. Laplace (1796) |
Hypothesis of D. Jeans (early 20th century) |
Hypothesis of Academician O.P. Schmidt (40s of XX century) |
Hypothesis of a Calemic V. G. Fesenkov (30s of XX century) |
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The planets were formed from gas-dust matter (in the form of a hot nebula). Cooling is accompanied by compression and an increase in the speed of rotation of some axis. Rings appeared at the equator of the nebula. The substance of the rings collected in red-hot bodies and gradually cooled down. |
A larger star once passed by the Sun, and gravity pulled out a jet of hot substance (a prominence) from the Sun. Condensations formed, from which later - planets |
The gas-dust cloud revolving around the Sun should have taken a solid shape as a result of the collision of particles and their movement. Particles coalesced into clusters. The attraction of smaller particles by clumps should have contributed to the growth of the surrounding matter. The orbits of the clumps should have become almost circular and lying almost in the same plane. Condensations were the embryos of the planets, absorbing almost all the matter from the gaps between their orbits. |
The Sun itself arose from a rotating cloud, and the planets from secondary condensations in this cloud. Further, the Sun greatly decreased and cooled to its present state. |
Rice. 3. Composition of the solar systems
Sun
Sun is a star, a giant hot ball. Its diameter is 109 times the diameter of the Earth, its mass is 330,000 times the mass of the Earth, but the average density is low - only 1.4 times the density of water. The sun is located at a distance of about 26,000 light years from the center of our galaxy and revolves around it, making one revolution in about 225-250 million years. The orbital speed of the Sun is 217 km/s, so it travels one light year in 1400 Earth years.
Rice. 4. The chemical composition of the Sun
The pressure on the Sun is 200 billion times higher than at the surface of the Earth. The density of solar matter and pressure rapidly increase in depth; the increase in pressure is explained by the weight of all overlying layers. The temperature on the surface of the Sun is 6000 K, and inside it is 13,500,000 K. The characteristic lifetime of a star like the Sun is 10 billion years.
Table 1. General information about the Sun
The chemical composition of the Sun is about the same as that of most other stars: about 75% is hydrogen, 25% is helium, and less than 1% is all other chemical elements (carbon, oxygen, nitrogen, etc.) (Fig. 4 ).
The central part of the Sun with a radius of approximately 150,000 km is called solar core. This is a nuclear reaction zone. The density of matter here is about 150 times higher than the density of water. The temperature exceeds 10 million K (on the Kelvin scale, in terms of degrees Celsius 1 ° C \u003d K - 273.1) (Fig. 5).
Above the core, at distances of about 0.2-0.7 of the radius of the Sun from its center, there is radiant energy transfer zone. Energy transfer here is carried out by absorption and emission of photons by individual layers of particles (see Fig. 5).
Rice. 5. Structure of the Sun
Photon(from Greek. phos- light), an elementary particle that can exist only by moving at the speed of light.
Closer to the surface of the Sun, vortex mixing of the plasma occurs, and the energy transfer to the surface occurs
predominantly by the movements of the substance itself. This type of energy transfer is called convection and the layer of the Sun, where it occurs, - convective zone. The thickness of this layer is approximately 200,000 km.
Above the convective zone is the solar atmosphere, which is constantly fluctuating. Both vertical and horizontal waves with lengths of several thousand kilometers propagate here. The oscillations occur with a period of about five minutes.
The inner layer of the sun's atmosphere is called photosphere. It consists of light bubbles. it granules. Their dimensions are small - 1000-2000 km, and the distance between them is 300-600 km. About a million granules can be simultaneously observed on the Sun, each of which exists for several minutes. The granules are surrounded by dark spaces. If the substance rises in the granules, then around them it falls. The granules create a general background against which one can observe such large-scale formations as torches, sunspots, prominences, etc.
sunspots- dark areas on the Sun, the temperature of which is lowered compared to the surrounding space.
solar torches called the bright fields surrounding sunspots.
prominences(from lat. protubero- I swell) - dense condensations of relatively cold (compared to the ambient temperature) matter that rise and are held above the surface of the Sun by a magnetic field. The origin of the magnetic field of the Sun can be caused by the fact that different layers of the Sun rotate at different speeds: the inner parts rotate faster; the core rotates especially fast.
Prominences, sunspots, and flares are not the only examples of solar activity. It also includes magnetic storms and explosions, which are called flashes.
Above the photosphere is chromosphere is the outer shell of the sun. The origin of the name of this part of the solar atmosphere is associated with its reddish color. The thickness of the chromosphere is 10-15 thousand km, and the density of matter is hundreds of thousands of times less than in the photosphere. The temperature in the chromosphere is growing rapidly, reaching tens of thousands of degrees in its upper layers. At the edge of the chromosphere are observed spicules, which are elongated columns of compacted luminous gas. The temperature of these jets is higher than the temperature of the photosphere. Spicules first rise from the lower chromosphere by 5000-10000 km, and then fall back, where they fade. All this happens at a speed of about 20,000 m/s. Spikula lives 5-10 minutes. The number of spicules existing on the Sun at the same time is about a million (Fig. 6).
Rice. 6. The structure of the outer layers of the Sun
The chromosphere surrounds solar corona is the outer layer of the sun's atmosphere.
The total amount of energy radiated by the Sun is 3.86. 1026 W, and only one two billionth of this energy is received by the Earth.
Solar radiation includes corpuscular and electromagnetic radiation.Corpuscular fundamental radiation- this is a plasma stream, which consists of protons and neutrons, or in other words - sunny wind, which reaches near-Earth space and flows around the entire Earth's magnetosphere. electromagnetic radiation is the radiant energy of the sun. It reaches the earth's surface in the form of direct and scattered radiation and provides a thermal regime on our planet.
In the middle of the XIX century. Swiss astronomer Rudolf Wolf(1816-1893) (Fig. 7) calculated a quantitative indicator of solar activity, known throughout the world as the Wolf number. Having processed the data on observations of sunspots accumulated by the middle of the last century, Wolf was able to establish the average 1-year cycle of solar activity. In fact, the time intervals between years of maximum or minimum Wolf numbers range from 7 to 17 years. Simultaneously with the 11-year cycle, a secular, more precisely 80-90-year cycle of solar activity takes place. Inconsistently superimposed on each other, they make noticeable changes in the processes taking place in the geographic envelope of the Earth.
A. L. Chizhevsky (1897-1964) (Fig. 8) pointed out the close connection of many terrestrial phenomena with solar activity back in 1936, who wrote that the vast majority of physical and chemical processes on Earth are the result of the influence of cosmic forces. He was also one of the founders of such a science as heliobiology(from Greek. helios- the sun), studying the influence of the Sun on the living substance of the geographic shell of the Earth.
Depending on solar activity, such physical phenomena occur on Earth, such as: magnetic storms, the frequency of auroras, the amount of ultraviolet radiation, the intensity of thunderstorm activity, air temperature, atmospheric pressure, precipitation, the level of lakes, rivers, groundwater, salinity and efficiency of the seas and others
The life of plants and animals is associated with the periodic activity of the Sun (there is a correlation between the solar cycle and the period of the growing season in plants, the reproduction and migration of birds, rodents, etc.), as well as humans (diseases).
At present, the relationship between solar and terrestrial processes continues to be studied with the help of artificial earth satellites.
terrestrial planets
In addition to the Sun, planets are distinguished in the Solar System (Fig. 9).
By size, geographical indicators and chemical composition, the planets are divided into two groups: terrestrial planets and giant planets. The terrestrial planets include, and. They will be discussed in this subsection.
Rice. 9. Planets of the solar system
Earth is the third planet from the Sun. A separate section will be devoted to it.
Let's summarize. The density of the matter of the planet depends on the location of the planet in the solar system, and, taking into account its size, the mass. How
The closer the planet is to the Sun, the higher its average density of matter. For example, for Mercury it is 5.42 g/cm2, Venus - 5.25, Earth - 5.25, Mars - 3.97 g/cm 3 .
The general characteristics of the terrestrial planets (Mercury, Venus, Earth, Mars) are primarily: 1) relatively small sizes; 2) high temperatures on the surface; and 3) high density of planet matter. These planets rotate relatively slowly on their axis and have few or no satellites. In the structure of the planets of the terrestrial group, four main shells are distinguished: 1) a dense core; 2) the mantle covering it; 3) bark; 4) light gas-water shell (excluding Mercury). Traces of tectonic activity have been found on the surface of these planets.
giant planets
Now let's get acquainted with the giant planets, which are also included in our solar system. It , .
Giant planets have the following general characteristics: 1) large size and mass; 2) quickly rotate around an axis; 3) have rings, many satellites; 4) the atmosphere consists mainly of hydrogen and helium; 5) have a hot core of metals and silicates in the center.
They are also distinguished by: 1) low surface temperatures; 2) low density of matter of the planets.
The solar system includes the central star and all natural space objects revolving around it. It was formed by gravitational compression of a gas and dust cloud approximately 4.57 billion years ago. The solar system includes 8 * planets, of which half belong to the terrestrial group: these are Mercury, Venus, Earth and Mars. They are also called the inner planets, in contrast to the outer giant planets Jupiter, Saturn, Uranus and Neptune, located outside the ring of minor planets.
1. Mercury
The closest planet to the Sun in the solar system is named after the ancient Roman god of trade, swift-footed Mercury, as it moves through the celestial sphere faster than other planets.
2. Venus
The second planet in the solar system was named after the ancient Roman goddess of love, Venus. This is the brightest object in the earth's sky after the Sun and the Moon and the only planet in the solar system named after a female deity.
3. Earth
The third planet from the Sun and the fifth largest among all the planets in the solar system has had its current name since 1400, but who exactly named it that way is unknown. The English Earth originated from an 8th-century Anglo-Saxon word meaning earth or ground. This is the only planet in the solar system with a name that is not related to Roman mythology.
4. Mars
The seventh largest planet in the solar system has a reddish tint to its surface, imparted by iron oxide. With such a "bloody" association, the object was named after the ancient Roman god of war Mars.
5. Jupiter
The largest planet in the solar system is named after the ancient Roman supreme god of thunder. 6. Saturn Saturn is the slowest planet in the solar system, which is symbolically reflected in its first name: it was given in honor of the ancient Greek god of time Kronos. In Roman mythology, the god of agriculture Saturn turned out to be an analogue of Kronos, and as a result, this name was assigned to the planet.
7. Uranus
The third largest and fourth largest planet in the solar system was discovered in 1781 by the English astronomer William Herschel. The tradition of naming the planets was continued, and the international community named the new celestial body in honor of the father of Kronos, the Greek god of the sky, Uranus.
8. Neptune
Discovered on September 23, 1846, Neptune was the first planet discovered through mathematical calculations, and not through regular observations. The large blue giant (this color is due to the hue of the atmosphere) is named after the Roman god of the seas.
Pluto in 2006, it lost the status of a planet in the solar system and was classified as a dwarf planet and the largest object in the Kuiper belt. It has been in the status of the ninth planet of the solar system since its discovery in 1930. The name "Pluto" was first proposed by an eleven-year-old schoolgirl from Oxford, Venetia Burney. She was interested not only in astronomy, but also in classical mythology, and decided that this name - the ancient Roman version of the name of the Greek god of the underworld - was best suited for a dark, distant and cold world. Astronomers chose this option by voting.
Look at the model of the solar system created in the American desert.
* Recently scientists . Since it does not yet have a full name, and research is still ongoing, we did not include it in the above list..
Welcome to the astronomy portal site dedicated to our Universe, space, large and small planets, star systems and their components. Our portal provides detailed information about all 9 planets, comets, asteroids, meteors and meteorites. You can learn about the origin of our Sun and the Solar System.
The sun, together with the nearest celestial bodies that revolve around it, form the solar system. The number of celestial bodies includes 9 planets, 63 satellites, 4 rings of giant planets, more than 20 thousand asteroids, a huge number of meteorites and millions of comets. Between them there is a space in which electrons and protons (particles of the solar wind) move. Although scientists and astrophysicists have been studying our solar system for a long time, there are still unexplored places. For example, most of the planets and their satellites have been studied only briefly from photographs. We saw only one hemisphere of Mercury, and no space probe flew to Pluto at all.
Almost the entire mass of the solar system is concentrated in the Sun - 99.87%. The size of the Sun in the same way exceeds the size of other celestial bodies. This is a star that shines on its own due to high surface temperatures. The planets surrounding it shine with the light reflected from the Sun. This process is called albedo. There are nine planets in total - Mercury, Venus, Mars, Earth, Uranus, Saturn, Jupiter, Pluto and Neptune. Distance in the solar system is measured in units of our planet's average distance from the sun. It is called an astronomical unit - 1 a.u. = 149.6 million km. For example, the distance from the Sun to Pluto is 39 AU, but sometimes this figure increases to 49 AU.
The planets revolve around the Sun in almost circular orbits that lie relatively in the same plane. In the plane of the Earth's orbit lies the so-called plane of the ecliptic, very close to the average of the plane of the orbits of the other planets. Because of this, the visible paths of the planets of the Moon and the Sun in the sky lie near the line of the ecliptic. The inclinations of the orbits begin their reading from the plane of the ecliptic. Those angles that have an inclination of less than 90⁰ correspond to counterclockwise motion (forward orbital motion), and angles greater than 90⁰ correspond to reverse motion.
In the solar system, all planets move in a forward direction. Pluto's largest orbital inclination is 17⁰. Most comets move in the opposite direction. For example, the same comet Halley - 162⁰. All the orbits of the bodies that are in our solar system are basically elliptical. The closest point of the orbit to the Sun is called perihelion, and the farthest point is called aphelion.
All scientists, taking into account terrestrial observation, divide the planets into two groups. Venus and Mercury, as the planets closest to the Sun, are called internal, and more distant external. The inner planets have a limiting angle of removal from the Sun. When such a planet is at its maximum east or west of the Sun, astrologers say that it is located at its greatest east or west elongation. And if the inner planet is visible in front of the Sun, it is located in inferior conjunction. When behind the Sun, it is in superior conjunction. Just like the Moon, these planets have certain phases of illumination during the synodic period Ps. The true orbital period of planets is called sidereal.
When an outer planet is behind the Sun, it is in conjunction. In the event that it is placed in the opposite direction to the Sun, it is said to be in opposition. That planet, which is observed at an angular distance of 90⁰ from the Sun, is considered as quadrature. The asteroid belt between the orbits of Jupiter and Mars divides the planetary system into 2 groups. The inner ones refer to the planets of the Earth group - Mars, Earth, Venus and Mercury. Their average density is from 3.9 to 5.5 g/cm 3 . They are devoid of rings, slowly rotate along the axis and have a small number of natural satellites. Earth has the Moon, and Mars has Deimos and Phobos. Behind the asteroid belt are the giant planets - Neptune, Uranus, Saturn, Jupiter. They are characterized by large radius, low density and deep atmosphere. There is no solid surface on such giants. They rotate very quickly, are surrounded by a large number of satellites and have rings.
In ancient times, people knew the planets, but only those that were visible to the naked eye. In 1781, V. Herschel discovered another planet - Uranus. In 1801, G. Piazzi discovered the first asteroid. Neptune was discovered twice, first theoretically by W. Le Verrier and J. Adams, and then physically by I. Galle. Pluto as the most distant planet was discovered only in 1930. Galileo discovered four moons of Jupiter in the 17th century. Since that time, numerous discoveries of other satellites have begun. All of them were made with the help of telescopes. H. Huygens first learned about the fact that Saturn is surrounded by a ring of asteroids. Dark rings around Uranus were discovered in 1977. The remaining space discoveries were mainly made by special machines and satellites. So, for example, in 1979, thanks to the Voyager 1 probe, people saw the transparent stone rings of Jupiter. And 10 years later, Voyager 2 discovered the heterogeneous rings of Neptune.
Our portal site will tell you basic information about the solar system, its structure and celestial bodies. We present only cutting-edge information that is relevant at the moment. The Sun itself is one of the most important celestial bodies in our galaxy.
The sun is at the center of the solar system. This is a natural single star with a mass of 2 * 1030 kg and a radius of approximately 700,000 km. The temperature of the photosphere - the visible surface of the Sun - 5800K. Comparing the gas density of the Sun's photosphere with the density of air on our planet, we can say that it is thousands of times less. Inside the Sun, density, pressure, and temperature increase with depth. The deeper, the more indicators.
The high temperature of the Sun's core affects the conversion of hydrogen into helium, resulting in a large amount of heat being released. Because of this, the star does not shrink under the influence of its own gravity. The energy that is released from the core leaves the Sun in the form of radiation from the photosphere. Radiation power - 3.86 * 1026 W. This process has been going on for about 4.6 billion years. According to approximate estimates of scientists, about 4% has already been processed from hydrogen into helium. Interestingly, 0.03% of the mass of the Star is converted into energy in this way. Considering the models of the life of the Stars, it can be assumed that the Sun has now passed half of its own evolution.
The study of the Sun is extremely difficult. Everything is connected precisely with high temperatures, but thanks to the development of technology and science, humanity is gradually mastering knowledge. For example, in order to determine the content of chemical elements on the Sun, astronomers study radiation in the light spectrum and absorption lines. Emission lines (emission lines) are very bright parts of the spectrum that indicate an excess of photons. The frequency of the spectral line indicates which molecule or atom is responsible for its appearance. The absorption lines are represented by dark gaps in the spectrum. They indicate missing photons of one frequency or another. And that means they are absorbed by some chemical element.
By studying the thin photosphere, astronomers estimate the chemical composition of its depths. The outer regions of the Sun are mixed by convection, the solar spectra are of high quality, and the physical processes responsible for them are explainable. Due to the lack of funds and technologies, only half of the lines of the solar spectrum have been intensified so far.
The sun is made up of hydrogen, followed by helium. It is an inert gas that does not react well with other atoms. Similarly, it is reluctant to show up in the optical spectrum. Only one line is visible. The entire mass of the Sun is 71% hydrogen and 28% helium. The remaining elements occupy a little more than 1%. Interestingly, this is not the only object in the solar system that has the same composition.
Sunspots are regions of the surface of a star with a large vertical magnetic field. This phenomenon prevents the gas from moving vertically, thereby suppressing convection. The temperature of this region drops by 1000 K, thus forming a spot. Its central part - "shadow", is surrounded by a higher temperature area - "penumbra". In size, such a spot in diameter slightly exceeds the size of the Earth. Its viability does not exceed a period of several weeks. There is no fixed number of sunspots. There may be more in one period and less in another. These periods have their own cycles. On average, their figure reaches 11.5 years. The viability of stains depends on the cycle, the longer it is, the less stains exist.
Fluctuations in the activity of the Sun practically do not affect the total power of its radiation. Scientists have long tried to find a link between Earth's climate and sunspot cycles. This solar phenomenon is associated with the event - "Maunder minimum". In the middle of the 17th century, for 70 years, our planet experienced the Little Ice Age. At the same time as this event, there was practically no spot on the Sun. Until now, it is not known exactly whether there is a connection between these two events.
In total, there are five large constantly rotating hydrogen-helium balls in the solar system - Jupiter, Saturn, Neptune, Uranus and the Sun itself. Inside these giants are almost all the substances of the solar system. Direct study of distant planets is not yet possible, so most of the unproven theories remain unproven. The same situation is with the bowels of the Earth. But people still found a way to somehow study the internal structure of our planet. Seismologists cope well with this issue by observing seismic tremors. Naturally, their own methods are quite applicable to the Sun. Unlike seismic terrestrial movements, constant seismic noise acts in the Sun. Under the converter zone, which occupies 14% of the Star's radius, matter rotates synchronously with a period of 27 days. Higher in the convective zone, rotation proceeds synchronously along cones of equal latitude.
More recently, astronomers have tried to apply seismological methods to the study of giant planets, but there have been no results. The fact is that the instruments used in this study cannot yet fix the emerging oscillations.
Above the photosphere of the Sun there is a thin, very hot layer of the atmosphere. It can only be seen during solar eclipses. It is called the chromosphere because of its red color. The chromosphere is about several thousand kilometers thick. From the photosphere to the top of the chromosphere, the temperature doubles. But it is still unknown why the energy of the Sun is released, leaves the chromosphere in the form of heat. The gas that is above the chromosphere is heated to one million K. This region is also called the corona. Along the radius of the Sun, it extends for one radius and has a very low density of gas inside it. Interestingly, at low gas density, the temperature is very high.
From time to time, gigantic formations are created in the atmosphere of our star - eruptive prominences. Having the shape of an arch, they rise from the photosphere to a great height of about half the solar radius. According to the observations of scientists, it turns out that the shape of the prominences is constructed by lines of force emanating from the magnetic field.
Another interesting and extremely active phenomenon is solar flares. These are very powerful emissions of particles and energy lasting up to 2 hours. Such a flow of photons from the Sun to the Earth reaches in eight minutes, and protons and electrons reach in a few days. Such flashes are created in places where the direction of the magnetic field changes sharply. They are caused by the movement of substances in sunspots.
> solar system
solar system- planets in order, Sun, structure, system model, satellites, space missions, asteroids, comets, dwarf planets, interesting facts.
solar system- a place in outer space in which the Sun, planets in order and many other space objects and celestial bodies are located. The solar system is the most precious place we live in, our home.
Our Universe is a huge place where we occupy a tiny corner. But for earthlings, the solar system seems to be the most immense territory, to the far corners of which we are only beginning to approach. And she still hides a lot of mysterious and mysterious formations. So, despite centuries of study, we have only slightly opened the door to the unknown. So what is the solar system? Today we will consider this issue.
Discovery of the solar system
The actual need to look into the sky and you will see our system. But few peoples and cultures understood exactly where we exist and what place we occupy in space. For a long time, we thought that our planet is static, located in the center, and the rest of the objects rotate around it.
But still, even in ancient times, supporters of heliocentrism appeared, whose ideas would inspire Nicolaus Copernicus to create a true model, where the Sun was located in the center.
In the 17th century, Galileo, Kepler and Newton were able to prove that the planet Earth revolves around the star Sun. The discovery of gravity helped to understand that other planets follow the same laws of physics.
The revolutionary moment came with the advent of the first telescope from Galileo Galilei. In 1610, he noticed Jupiter and its satellites. This will be followed by the discovery of other planets.
In the 19th century, three important observations were made that helped to calculate the true nature of the system and its position in space. In 1839, Friedrich Bessel successfully identified an apparent shift in stellar position. This showed that there is a huge distance between the Sun and the stars.
In 1859, G. Kirchhoff and R. Bunsen used a telescope to conduct a spectral analysis of the Sun. It turned out that it consists of the same elements as the Earth. The parallax effect is visible in the lower figure.
As a result, Angelo Secchi was able to compare the spectral signature of the Sun with the spectra of other stars. It turned out that they almost converge. Percival Lowell carefully studied the distant corners and orbital paths of the planets. He guessed that there was still an undiscovered object - Planet X. In 1930, Clyde Tombaugh noticed Pluto at his observatory.
In 1992, scientists expand the boundaries of the system by discovering a trans-Neptunian object - 1992 QB1. From this moment begins the interest in the Kuiper belt. The following are the finds of Eris and other objects from the team of Michael Brown. All of this will lead to an IAU meeting and the removal of Pluto from planetary status. Below you can study in detail the composition of the solar system, considering all the solar planets in order, the main star the Sun, the asteroid belt between Mars and Jupiter, the Kuiper belt and the Oort Cloud. The solar system also hides the largest planet (Jupiter) and the smallest (Mercury).
Structure and composition of the solar system
Comets are lumps of snow and mud filled with frozen gas, rocks, and dust. The closer they get to the Sun, the more they heat up and throw out dust and gas, increasing their brightness.
Dwarf planets rotate around the star, but could not remove foreign objects from orbit. They are inferior in size to standard planets. The most famous representative is Pluto.
The Kuiper Belt lurks outside of Neptune's orbit, filled with icy bodies and formed into a disk. The most famous representatives are Pluto and Eris. Hundreds of ice dwarfs live on its territory. Farthest away is the Oort Cloud. Together they act as a source of incoming comets.
The solar system is only a small part of the Milky Way. Beyond its borders is a large-scale space filled with stars. At light speed, it would take 100,000 years to fly over the entire area. Our galaxy is one of many in the universe.
At the center of the system is the main and only star - the Sun (main sequence G2). The first are 4 terrestrial planets (inner), the asteroid belt, 4 gas giants, the Kuiper belt (30-50 AU) and the spherical Oort Cloud, extending to 100,000 AU. to the interstellar medium.
The sun holds 99.86% of the total systemic mass, and gravity outweighs all forces. Most of the planets are located near the ecliptic and rotate in the same direction (counterclockwise).
Approximately 99% of the planetary mass is represented by gas giants, where Jupiter and Saturn cover more than 90%.
Informally, the system is divided into several sections. The inner one includes 4 terrestrial planets and an asteroid belt. Next comes the outer system with 4 giants. Separately, a zone with trans-Neptunian objects (TNOs) is distinguished. That is, you can easily find the outer line, as it is marked by the large planets of the solar system.
Many planets are considered mini-systems, as they have a group of satellites. Gas giants also have rings - small bands of small particles rotating around the planet. Usually large moons arrive in a gravitational block. On the lower layout, you can see a comparison of the sizes of the Sun and the planets of the system.
The sun is 98% hydrogen and helium. Earth-type planets are endowed with silicate rock, nickel and iron. Giants are composed of gases and ices (water, ammonia, hydrogen sulfide and carbon dioxide).
The bodies of the solar system distant from the star have low temperature indicators. Ice giants (Neptune and Uranus), as well as small objects beyond their orbits, are isolated from here. Their gases and ices are volatile substances capable of condensing at a distance of 5 AU. from the sun.
The origin and evolutionary process of the solar system
Our system appeared 4.568 billion years ago as a result of the gravitational collapse of a large-scale molecular cloud, represented by hydrogen, helium and a small amount of heavier elements. This mass collapsed, which led to a rapid rotation.
Most of the mass gathered in the center. The temperature mark rose. The nebula contracted, increasing acceleration. This led to flattening into a protoplanetary disk with a red-hot protostar.
Due to the high level of boiling near the star, only metals and silicates can exist in solid form. As a result, 4 terrestrial planets appeared: Mercury, Venus, Earth and Mars. Metals were scarce, so they were unable to increase their size.
But the giants appeared farther away, where the material was cool and allowed the volatile ice compounds to remain in a solid state. There was much more ice, so the planets dramatically increased their scale, attracting huge amounts of hydrogen and helium into the atmosphere. The remnants failed to become planets and settled in the Kuiper Belt or moved to the Oort Cloud.
For 50 million years of development, the pressure and density of hydrogen in the protostar triggered nuclear fusion. Thus the Sun was born. The wind created the heliosphere and scattered gas and dust into space.
The system is still in its original state. But the Sun develops and after 5 billion years completely transforms hydrogen into helium. The core will collapse, releasing a huge energy reserve. The star will increase 260 times and become a red giant.
This will lead to the death of Mercury and Venus. Our planet will lose life because it will heat up. As a result, the outer stellar layers will break out into space, leaving behind a white dwarf, the size of our planet. A planetary nebula will form.
inner solar system
This is the line with the first 4 planets from the star. All of them have similar parameters. This is a rocky type, represented by silicates and metals. Located closer than the giants. They are inferior in density and size, and are also deprived of huge lunar families and rings.
Silicates form the crust and mantle, while metals are part of the cores. All, except Mercury, have an atmospheric layer that allows you to shape weather conditions. Impact craters and tectonic activity are visible on the surface.
Closest to the star is Mercury. It is also the smallest planet. The magnetic field reaches only 1% of that of the Earth, and the thin atmosphere leads to the fact that the planet is half hot (430°C) and freezes (-187°C).
Venus converges in size with the Earth and has a dense atmospheric layer. But the atmosphere is extremely toxic and works as a greenhouse. 96% consists of carbon dioxide, along with nitrogen and other impurities. Dense clouds are made from sulfuric acid. There are many canyons on the surface, the deepest of which reaches 6400 km.
Earth best studied because it is our home. It has a rocky surface covered with mountains and depressions. In the center is a heavy metal core. Water vapor is present in the atmosphere, which smoothes the temperature regime. The moon revolves nearby.
Because of the appearance Mars was nicknamed the Red Planet. The color is created by the oxidation of iron materials on the top layer. It is endowed with the largest mountain in the system (Olympus), rising to 21229 m, as well as the deepest canyon - the Mariner Valley (4000 km). Much of the surface is ancient. There are ice caps at the poles. A thin atmospheric layer hints at water deposits. The core is solid, and next to the planet there are two satellites: Phobos and Deimos.
outer solar system
Gas giants are located here - large-scale planets with lunar families and rings. Despite their size, only Jupiter and Saturn can be seen without the use of telescopes.
The largest planet in the solar system is Jupiter with a rapid rotational speed (10 hours) and an orbital path of 12 years. The dense atmospheric layer is filled with hydrogen and helium. The core can reach the size of the Earth. There are many satellites, faint rings, and the Great Red Spot, a powerful storm that has been unsettled for the 4th century.
Saturn- a planet that is recognized by its chic ring system (7 pieces). There are satellites in the system, and the hydrogen and helium atmosphere rotates rapidly (10.7 hours). It takes 29 years to go around the star.
In 1781 William Herschel found Uranus. A day on the giant lasts 17 hours, and it takes 84 years to orbit. It holds a huge amount of water, methane, ammonia, helium and hydrogen. All this is concentrated around the stone core. There is a lunar family and rings. Voyager 2 flew to it in 1986.
Neptune- a distant planet with water, methane, ammonium, hydrogen and helium. There are 6 rings and dozens of satellites. Voyager 2 also flew by in 1989.
Trans-Neptunian region of the solar system
Thousands of objects have already been found in the Kuiper belt, but it is believed that up to 100,000 with a diameter of more than 100 km live there. They are extremely small and located at large distances, so it is difficult to calculate the composition.
Spectrographs show an ice mixture: hydrocarbons, water ice and ammonia. Initial analysis showed a wide range of colors from neutral to bright red. This hints at the richness of the composition. A comparison of Pluto and KBO 1993 SC showed that they are extremely different in surface elements.
Water ice was found in 1996 TO66, 38628 Huya and 20000 Varuna, and crystalline ice was seen in Quaoar.
The Oort Cloud and Beyond the Solar System
This cloud is believed to extend from 2000-5000 AU. and up to 50,000 a.u. from a star. The outer edge can stretch up to 100,000-200,000 AU. The cloud is divided into two parts: outer spherical (20000-50000 AU) and inner (2000-20000 AU).
The outer one is inhabited by trillions of bodies with a diameter of a kilometer or more, as well as billions with a width of 20 km. There is no exact information about the mass, but it is believed that Halley's comet is a typical representative. The total mass of the cloud is 3 x 10 25 km (5 lands).
If we focus on comets, then most of the cloud bodies are represented by ethane, water, carbon monoxide, methane, ammonia and hydrogen cyanide. The population of 1-2% consists of asteroids.
Bodies from the Kuiper Belt and the Oort Cloud are called Trans-Neptunian Objects (TNOs) because they are further away from Neptune's orbital path.
Exploring the solar system
The size of the solar system still seems immense, but our knowledge has expanded significantly with the sending of probes into outer space. The boom in the study of outer space began in the middle of the 20th century. Now it can be noted that all solar planets have been approached at least once by terrestrial vehicles. We have photos, videos, as well as analysis of the soil and atmosphere (for some).
The first artificial spacecraft was the Soviet Sputnik-1. He was sent into space in 1957. Spent several months in orbit collecting atmospheric and ionospheric data. In 1959, the United States joined with Explorer 6, which first took pictures of our planet.
These devices provided a huge array of information about planetary features. Luna-1 was the first to go to another object. He raced past our satellite in 1959. Mariner became a successful mission to Venus in 1964, Mariner 4 arrived at Mars in 1965, and the 10th flight in 1974 passed Mercury.
Since the 1970s the attack on the outer planets begins. Pioneer 10 flew past Jupiter in 1973, and the next mission visited Saturn in 1979. The real breakthrough was the Voyagers, which circled the large giants and their satellites in the 1980s.
The Kuiper Belt is being handled by New Horizons. In 2015, the device successfully reached Pluto, sending the first close pictures and a lot of information. Now he rushes to the distant TNO.
But we yearned to land on another planet, so rovers and probes began to be sent in the 1960s. Luna 10 was the first to enter lunar orbit in 1966. In 1971, Mariner 9 settled near Mars, and Verena 9 orbited the second planet in 1975.
Galileo first swirled near Jupiter in 1995, and the famous Cassini appeared near Saturn in 2004. MESSENGER and Dawn visited Mercury and Vesta in 2011. And the latter still managed to fly around the dwarf planet Ceres in 2015.
The first spacecraft to land on the surface was Luna 2 in 1959. This was followed by landings on Venus (1966), Mars (1971), asteroid 433 Eros (2001), Titan and Tempel in 2005.
Now controlled vehicles have visited only Mars and the Moon. But the first robotic was Lunokhod 1 in 1970. Spirit (2004), Opportunity (2004) and Curiosity (2012) landed on Mars.
The 20th century was marked by the space race between America and the USSR. For the Soviets, this was the East program. The first mission came in 1961, when Yuri Gagarin was in orbit. In 1963, the first woman flew - Valentina Tereshkova.
In the United States, the Mercury project was developed, where they also planned to take people into space. The first American to go into orbit was Alan Shepard in 1961. After the end of both programs, countries focused on long-term and short-term flights.
The main goal was to land a man on the moon. The USSR was developing a capsule for 2-3 people, and the Gemini were trying to create a device for a safe lunar landing. In 1969, Apollo 11 ended up successfully landing Neil Armstrong and Buzz Aldrin on the satellite. In 1972, they completed 5 more landings, and all were Americans.
The next challenge was the creation of a space station and reusable vehicles. The Soviets formed the Salyut and Almaz stations. The first station with a large number of crews was NASA Skylab. The first settlement was the Soviet Mir, functioning in 1989-1999. It was replaced by the International Space Station in 2001.
The only reusable spacecraft was Columbia, which completed several orbital passes. 5 shuttles completed 121 missions, and retired in 2011. Due to accidents, two shuttles crashed: Challenger (1986) and Columbia (2003).
In 2004, George W. Bush announced his intention to return to the moon and conquer the Red Planet. This idea was supported by Barack Obama. As a result, now all the forces are spent on the exploration of Mars and plans to create a human colony.
All these flights and sacrifices have led to a better understanding of our system, its past and future. In the current model, there are 8 planets, 4 dwarfs and a huge number of TNOs. Let's not forget about the army of asteroids and planetosimals.
On the page you can find out not only useful information about the solar system, its structure and size, but also get a detailed description and characteristics of all the planets in order with names, photos, videos, diagrams and an indication of the distance from the Sun. The composition and structure of the solar system will no longer be a mystery. Also use our 3D model to explore all the celestial bodies on your own.
It's hard to believe, but once the Cosmos was completely empty. There were no planets, no satellites, no stars. Where did they come from? How was the solar system formed? These questions have troubled mankind for centuries. This article will help to give some idea of what the Cosmos is and will reveal interesting facts about the planets of the solar system.
How it all began
The Universe is the entire visible and invisible Cosmos, together with all existing cosmic bodies. Several theories have been put forward:
3. Divine intervention. Our Universe is so unique, everything in it is thought out to the smallest detail, that it could not arise by itself. Only the Great Creator is capable of creating such a miracle. Absolutely not a scientific theory, but it has the right to exist.
Disputes about the causes of the true origin of outer space continue. In fact, we have an idea of the solar system, which includes a burning star and eight planets with their satellites, galaxies, stars, comets, black holes and much more.
Amazing discoveries or interesting facts about the planets of the solar system
Outer spaces beckon with their mystery. Each celestial body keeps its own mystery. Thanks to astronomical discoveries, valuable information about heavenly wanderers appears.
Closest to the sun is Mercury. There is an opinion that it was once a satellite of Venus. But as a result of a cosmic catastrophe, the cosmic body separated from Venus and acquired its own orbit. A year on Mercury is 88 days, and a day is 59 days.
Mercury is the only planet in the solar system where you can observe the movement of the Sun in the opposite direction. This phenomenon has a completely logical explanation. The speed of rotation of the planet around its axis is much slower than the movement in its orbit. Due to such a difference in speed regimes, the effect of changing the movement of the Sun arises.
On Mercury you can observe a fantastic phenomenon: two sunsets and sunrises. And if you move to the meridians 0˚ and 180̊, then you can witness three sunsets and sunrises per day.
Venus goes next to Mercury. Lights up in the sky during sunset on Earth, but you can observe it for only a couple of hours. Because of this feature, she was nicknamed "Evening Star". Interestingly, the orbit of Venus lies inside the orbit of our planet. But it moves in the opposite direction, counterclockwise. A year on the planet lasts 225 days, and 1 day is 243 Earth days. Venus, like the Moon, has a phase change, transforming either into a thin sickle or into a wide circle. There is an assumption that some types of terrestrial bacteria can live in the atmosphere of Venus.
Earth- truly a pearl of the solar system. Only on it there is a huge variety of life forms. People feel so comfortable on this planet and do not even realize that it is rushing along its orbit at a speed of 108,000 km per hour.
The fourth planet from the Sun is Mars. He is accompanied by two companions. A day on this planet is equivalent in duration to the earth - 24 hours. But 1 year lasts 668 days. Just like on Earth, the seasons change here. Seasons cause changes in the appearance of the planet.
Jupiter- the largest space giant. It has many satellites (more than 60 pieces) and 5 rings. It is 318 times the mass of Earth. But, despite its impressive size, it moves quite quickly. It turns around its own axis in just 10 hours, but it overcomes the distance around the Sun in 12 years.
The weather on Jupiter is bad - constant storms and hurricanes, accompanied by lightning. A striking representative of such weather conditions is the Great Red Spot - a whirlwind moving at a speed of 435 km / h.
hallmark Saturn, certainly are his rings. These flat formations are made up of dust and ice. The thickness of the circles ranges from 10 - 15 m to 1 km, the width from 3,000 km to 300,000 km. The rings of the planet are not a single whole, but represent formations in the form of thin spokes. Also, the planet is surrounded by more than 62 satellites.
Saturn has an incredibly high rate of rotation, so much so that it is compressed at the poles. A day on the planet lasts 10 hours, a year - 30 years.
Uranus, like Venus, it moves around the star counterclockwise. The uniqueness of the planet lies in the fact that it "lies on its side", its axis is tilted at an angle of 98˚. There is a theory that the planet took this position after a collision with another space object.
Like Saturn, Uranus has a complex ring system consisting of a combination of an inner and outer group of rings. In total, Uranus has 13 of them. It is believed that the rings are the remains of the former satellite of Uranus, which collided with the planet.
Uranus does not have a solid surface, a third of the radius, approximately 8,000 km, is a gaseous shell.
Neptune is the last planet in the solar system. It is surrounded by 6 dark rings. The most beautiful shade of the sea wave to the planet is given by methane, which is present in the atmosphere. Neptune makes one revolution in its orbit in 164 years. But around its axis it moves quite quickly, and the day passes for
16 hours. In some places, the orbit of Neptune intersects with the orbit of Pluto.
Neptune has a large number of moons. Basically, they all rotate in front of the orbit of Neptune and are called internal. There are only two outer satellites accompanying the planet.
You can see it on Neptune. However, outbreaks are too weak and occur throughout the planet, and not exclusively at the poles, as on Earth.
Once in space, there were 9 planets. This number also included Pluto. But due to its small size, the astronomical community has identified it as a series of dwarf planets (asteroids).
These are interesting facts and amazing stories about the planets of the solar system that are revealed in the process of exploring the black depths of the Cosmos.
