What is a solar system? All the planets in order
What is the solar system in which we live? The answer will be as follows: this is our central star, the Sun, and all the cosmic bodies that revolve around it. These are large and small planets, as well as their satellites, comets, asteroids, gases and cosmic dust.
The name of the solar system was given by the name of its star. In a broad sense, the term "solar" is often understood to mean any star system.
How did the solar system originate
According to scientists, the solar system was formed from a giant interstellar cloud of dust and gases due to gravitational collapse in a separate part of it. As a result, a protostar was formed in the center, then turned into a star — the Sun, and a huge protoplanetary disk, from which all the components of the Solar System listed above were subsequently formed. The process, as scientists believe, began about 4.6 billion years ago. This hypothesis was called nebular.Thanks to Emmanuel Swedenborg, Immanuel Kant and Pierre-Simon Laplace, who offered it as early as the 18th century, it eventually became generally accepted, but over the course of many decades it was refined, new data were entered into it taking into account the knowledge of modern sciences. Thus, it is assumed that, due to the increase and intensification of collisions of particles with each other, the temperature of the object grew, and after it reached the index of several thousand kelvins, the protostar gained luminescence. When the temperature index reached millions of kelvins, a thermonuclear fusion reaction began in the center of the future sun - the conversion of hydrogen to helium. It turned into a star.
The sun and its features
Our body scientists refer to the type of yellow dwarfs (G2V) by spectral classification. This is the closest star to us, its light reaches the surface of the planet in just 8.31 seconds. From the Earth, it seems that the radiation has a yellow tint, although in reality it is almost white.
The main components of our luminary are helium and hydrogen. In addition, due to spectral analysis, it was found that iron, neon, chromium, calcium, carbon, magnesium, sulfur, silicon, and nitrogen are present on the sun.Thanks to the thermonuclear reaction that goes on continuously in its depths, all life on Earth receives the necessary energy. Sunlight is an integral component of photosynthesis, as a result of which oxygen is produced. Without sunlight, it would be impossible, therefore, an atmosphere suitable for the protein life form could not have been formed either.
This is the nearest planet to our luminary. Together with the Earth, Venus and Mars, it belongs to the planets of the so-called terrestrial group. The name Mercury was due to the high speed of movement, which, according to myths, was distinguished by the fleet-footed ancient god. Mercury year is 88 days.
The planet is small, its radius is only 2439.7, and it is smaller in size than some large satellites of the giant planets, Ganymede and Titan. However, unlike them, Mercury is quite heavy (3.3 · 1023kg), and its density is only slightly behind the earth. This is due to the presence of the planet heavy dense core of iron.
There is no change of seasons on the planet. Its desert surface resembles the Moon. It is also covered with craters, but even less suitable for life. So, on the day side of Mercury, the temperature reaches + 510 ° С,and at night -210 ° C. These are the sharpest drops in the entire solar system. The atmosphere of the planet is very thin and sparse.
This planet, named after the ancient Greek goddess of love, more than others in the solar system is similar to the Earth in its physical parameters - mass, density, size, volume. For a long time, they were considered twin planets, but over time it turned out that their differences were enormous. So, Venus has no companions at all. Its atmosphere consists of carbon dioxide by almost 98%, and the pressure on the surface of the planet is 92 times that of the earth! Clouds above the surface of the planet, consisting of sulfuric acid vapor, never dissipate, and the temperature here reaches +434 ° C. Acid rains are raining on the planet, thunderstorms rage. Here is a high volcanic activity. Life in our understanding on Venus cannot exist, moreover, the descent capsules in such an atmosphere do not survive for long.
This planet is clearly visible in the night sky. This is the third brightest object for the earth observer, it shines with white light and exceeds all the stars in brightness. The distance to the Sun is 108 million km. Around the Sun it makes a revolution in 224 Earth days, and around its own axis - in 243.
Earth and Mars
These are the last planets of the so-called terrestrial group, whose representatives are characterized by the presence of a solid surface. In their structure, the core, the mantle and the crust are distinguished (it is not only in Mercury).
Mars has a mass equal to 10% of the mass of the Earth, which, in turn, is 5.9726 · 1024kg Its diameter is 6,780 km, almost half as large as ours. Mars is the seventh largest planet in the solar system. Unlike the Earth, 71% of the surface of which is covered by oceans, on Mars is solid land. Water is preserved under the surface of the planet in the form of a massive ice sheet. Its surface has a reddish tint due to the high content of iron oxide in the form of maghemite.
The atmosphere of Mars is very rarefied, and the pressure on the surface of the planet is less than the usual 160 times. On the surface of the planet there are craters of impact origin, volcanoes, depressions, deserts and valleys, and at the poles there are ice caps, just like on Earth.
The Martian day is slightly longer than the Earth, and the year is 668.6 days. Unlike the Earth, which has one moon, the planet has two irregular-shaped satellites - Phobos and Deimos. Both of them, like the Moon to the Earth, are constantly turned to Mars by the same side.Phobos is gradually approaching the surface of its planet, moving in a spiral, and is likely to fall on it over time or break up into parts. Deimos, by contrast, is gradually moving away from Mars and, in the distant future, may leave its orbit.
Between the orbits of Mars and the next planet, Jupiter, is the belt of asteroids consisting of small celestial bodies.
Jupiter and Saturn
What is the largest planet? There are four gas giants in the solar system: Jupiter, Saturn, Uranus and Neptune. The largest size of them has Jupiter. Its atmosphere, like that of the Sun, consists predominantly of hydrogen. The fifth planet, named after the god of thunder, has an average radius of 69911 km and a mass that is 318 times the Earth’s. The magnetic field of the planet is 12 times stronger than the earth. Its surface is hidden under opaque clouds. While scientists find it difficult to say with certainty what processes can occur under this dense curtain. It is assumed that on the surface of Jupiter - boiling hydrogen ocean. Astronomers consider this planet a “failed star” due to some similarity of their parameters.
Jupiter has 39 satellites, 4 of which - Io, Europa, Ganymede and Callisto - are still discovered by Galileo.
Saturn is slightly smaller than Jupiter, it is the second largest among the planets.This is the sixth, next planet, also consisting of hydrogen with impurities of helium, a small amount of ammonia, methane, water. Here hurricanes are raging, the speed of which can reach 1,800 km / h! Saturn's magnetic field is not as powerful as Jupiter’s, but stronger than Earth’s. Both Jupiter and Saturn, due to the rotation, are somewhat flattened at the poles. Saturn is 95 times heavier than earth, but its density is less than that of water. This is the least dense celestial body in our system.
The year on Saturn lasts 29.4 Earth, a day - 10 h 42 min. (in Jupiter, the year is 11, 86 earthly, the day is 9 h 56 min.). It has a system of rings consisting of solid particles of various sizes. Presumably, these may be the remains of a collapsed satellite of the planet. Saturn's total number of satellites is 62.
Uranus and Neptune - the last planets
The seventh planet of the solar system is Uranus. It is 2.9 billion km away from the Sun. Uranus is the third in size among the planets of the Solar System (the average radius is 25,362 km) and the fourth in mass (surpasses that of Earth in 14.6 times). The year here lasts 84 terrestrial, a day - 17.5 hours. In the atmosphere of this planet, in addition to hydrogen and helium, methane takes a significant amount. Therefore, for an earthly observer, Uranus has a pale blue color.
Uranus is the coldest planet in the solar system.The temperature of its atmosphere is unique: -224 ° C. Why scientists on Uranus have a lower temperature than on planets that are farther from the Sun is unknown.
This planet has 27 satellites. Uranus has thin flat rings.
Neptune, the eighth planet from the Sun, ranks fourth in size (average radius - 24,622 km) and third in mass (17 Earth). For the gas giant, it is relatively small (only four times the size of Earth). Its atmosphere also mainly consists of hydrogen, helium and methane. Gas clouds in its upper layers are moving at a record speed, the highest in the solar system - 2000 km / h! Some scientists believe that under the surface of the planet, under a layer of frozen gases and water, hidden, in turn, by the atmosphere, a solid stone core can hide.
These two planets are similar in composition, and therefore they are sometimes referred to a separate category, the ice giants.
Small planets are called celestial bodies, which also move around the Sun in their own orbits, but differ from other planets in insignificant sizes. Previously, they included asteroids, but more recently, namely, since 2006, these include Pluto, which was previously on the list of planets in the solar system and was the last, the tenth.This is due to changes in terminology. Thus, not only asteroids now belong to the minor planets, but also dwarf planets - Eris, Ceres, Makemake. They were called plutoids after Pluto. The orbits of all known dwarf planets are located beyond the orbit of Neptune, in the so-called Kuiper belt, which is much wider and more massive than the asteroid belt. Although the nature of them, as scientists believe, is the same: it is “unused” material remaining after the formation of the Solar System. Some scientists have suggested that the asteroid belt is the wreckage of the ninth planet, Phaeton, which died as a result of a global catastrophe.
About Pluto, it is known that it consists mainly of ice and solid rocks. The main component of its ice sheet is nitrogen. Its poles are covered with eternal snow.
This is the order of the planets of the solar system, according to modern concepts.
Parade of planets. Types of parades
This is a very interesting phenomenon for those interested in astronomy. The parade of the planets is called their position in the solar system, when some of them, continuously moving in their orbits, for a short time occupy a certain position for an earthly observer, as if lining up along one line.
The visible parade of the planets in astronomy is a special position of the five brightest for the people of the planets of the Solar System - Earth, Mercury, Venus, Mars, and also two giants - Jupiter and Saturn. At this time, the distance between them is relatively small and they are clearly visible on a small sector of the sky.
There are two types of parades. The big is called its kind, when five celestial bodies line up in one line. Small - when there are only four. These phenomena can be visible or invisible from different parts of the globe. In this case, a large parade is quite rare - once every several decades. Small can be observed once every few years, and the so-called mini-parade, in which only three planets participate, is practically annually.
Interesting facts about our planetary system
Venus, the only one of all the major planets of the solar system, rotates around its axis in the direction opposite to its rotation around the sun.
The highest mountain on the major planets of the Solar System is Olympus (21.2 km, diameter - 540 km), an extinct volcano on Mars. Not so long ago, on the largest asteroid of our star system, Veste, a peak was discovered, somewhat superior to Olympus in terms of parameters. Perhaps it is the highest in the solar system.
The four Galilean satellites of Jupiter are the largest in the solar system.
In addition to Saturn, all gas giants, some asteroids and the satellite of Saturn Rhea have rings.
What is the star system for us - the closest? The solar system is closest to the star system of the triple star Alpha Centauri (4, 36 light-years). It is assumed that there may exist planets like Earth.
Kids about the planets
How to explain to children what the solar system is? Here will help her model, which can be done together with the kids. To create planets, you can use plasticine or finished plastic (rubber) balls, as shown below. At the same time, it is necessary to keep the ratio between the dimensions of the “planets” so that the model of the solar system really helps to form the right ideas about space in children.
You will also need toothpicks that will hold our heavenly bodies, and as a background you can use a dark sheet of cardboard with painted small dots imitating stars. With the help of such an interactive toy, it will be easier for children to understand what a solar system is.
Future of the solar system
The article described in detail what the Solar System is. Despite its apparent stability, our Sun, like everything else in nature, is evolving, but this process, by our standards, is very long. The supply of hydrogen fuel in its depths is huge, but not infinite. So, according to the hypotheses of scientists, it will end in 6.4 billion years. As it burns out, the core of the sun will become denser and hotter, and the outer shell of the luminary will grow wider. The luminosity of the star will also increase. It is assumed that in 3.5 billion years due to this, the climate on Earth will be similar to Venusian, and life on it, in the usual sense, will no longer be possible. Water will not remain at all, under the action of high temperatures, it will evaporate into outer space. Subsequently, according to scientists, the Earth will be absorbed by the Sun and dissolve in its depths.
The prospect is not too bright. However, progress does not stand still, and, perhaps, by that time, new technologies will allow humanity to master other planets over which other suns shine. After all, how many "solar" systems in the world, scientists are not yet aware.Probably, there are countless of them, and among them it is quite possible to find habitable people. What kind of "solar" system will become our new home is not so important.