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Concepts of modern Natural Science Section: Textbooks
The solar system consists of a central celestial body – the Sun's star, 9 large planets orbiting around it, their satellites, many small asteroid planets, numerous comets and the interplanetary medium.
The major planets are arranged in the order of distance from the Sun as follows: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto.
The last three planets can be observed from Earth only with telescopes.
The rest are visible as more or less bright circles and have been known to people since ancient times.
One of the important issues related to the study of our planetary system is the problem of its origin.
The solution of this problem has a natural scientific, ideological and philosophical significance.
For centuries and even millennia, scientists have been trying to find out the past, present and future of the universe, including the Solar system.
However, the possibilities of planetary cosmology remain very limited to this day – only meteorites and samples of lunar rocks are still available for experiment in laboratory conditions.
The possibilities of the comparative method of research are also limited: the structure and laws of other planetary systems have not yet been sufficiently studied.
To date, there are many hypotheses about the origin of the Solar system, including independently proposed by the German philosopher Immanuel Kant (1724-1804) and the French mathematician and physicist P. Laplace (1749-1827).
Point of view of Kant was the evolutionary development of the cold dust of the nebula, the entrance of which first emerged of a massive Central body, the Sun, and then born and the planet.
P. Laplace considered the original nebula gas and very hot, in a state of rapid rotation.
Shrinking under the influence of the force of universal gravity, the nebula, due to the law of conservation of angular momentum, rotated faster and faster.
Under the influence of large centrifugal forces arising from rapid rotation in the equatorial belt, rings were sequentially separated from it, turning into planets as a result of cooling and condensation.
Thus, according to the theory of P. Laplace, the planets were formed before the Sun.
Despite such a difference between the two hypotheses under consideration, both of them come from the same idea – the Solar system arose as a result of the natural development of the nebula.
And that is why such an idea is sometimes called the Kant Laplace hypothesis.
According to modern ideas, the planets of the solar system were formed from a cold gas dust cloud that surrounded the Sun billions of years ago.
This point of view is most consistently reflected in the hypothesis of the Russian scientist, academician O. Y. Schmidt (1891-1956), who showed that the problems of cosmology can be solved by the coordinated efforts of astronomy and Earth sciences, primarily geography, geology, geochemistry.
The hypothesis of O. Y. Schmidt is based on the idea of the formation of planets by combining solid bodies and dust particles.
The gas dust cloud that appeared near the Sun at first consisted of 98% hydrogen and helium.
The remaining elements condensed into dust particles.
The erratic movement of gas in the cloud quickly stopped: it was replaced by the calm movement of a cloud around the Sun.
Dust particles were concentrated in the central plane, forming a layer of increased density.
When the layer density has reached a certain critical value, its own
gravity began to "compete" with the gravity of the Sun.
The dust layer turned out to be unstable and broke up into separate dust clumps.
Colliding with each other, they formed many solid dense bodies.
The largest of them acquired almost circular orbits and began to overtake other bodies in their growth, becoming potential embryos of future planets.
As more massive bodies, the neoplasms attached to themselves the remaining substance of the gas dust cloud.
In the end, nine large planets were formed, the movement of which in orbits remains stable for billions of years.
Taking into account the physical characteristics, all the planets are divided into two groups.
One of them consists of relatively small planets of the Earth group Mercury, Venus, Earth and Mapca.
Their substance is characterized by a relatively high density: on average, about 5.5 g/cm3, which is 5.5 times higher than the density of water.
Another group consists of the giant planets: Jupiter, Saturn, Uranus and Neptune.
These planets have huge masses.
Thus, the mass of Uranus is equal to 15 Earth masses, and Jupiter 318.
The giant planets consist mainly of hydrogen and helium, and the average density of their substance is close to the density of water.
Apparently, these planets do not have a solid surface, similar to the surface of the planets of the Earth group.
A special place is occupied by the ninth planet – Pluto, discovered in March 1930.
In terms of its size, it is closer to the planets of the Earth group.
Not so long ago, it was discovered that Pluto is a double planet: it consists of a central body and a very large satellite.
Both celestial bodies revolve around a common center of mass.
During the formation of planets, their division into two groups is due to the fact that the temperature was low in the parts of the cloud far from the Sun and all substances, except hydrogen and helium, formed solid particles.
Methane, ammonia and water predominated among them, which determined the composition of Uranus and Neptune.
The composition of the most massive planets – Jupiter and Saturn, in addition, turned out to be a significant amount of gases.
In the region of the planets of the Earth group, the temperature was much higher, and all volatile substances (including methane and ammonia) remained in a gaseous state, and, therefore, did not enter the planets.
The planets of this group were formed mainly from silicates and metals.
The process of formation of the Solar system cannot be considered thoroughly studied, and the proposed hypotheses are perfect.
For example, the considered hypothesis did not take into account the influence of electromagnetic interaction in the formation of planets.
Finding out this and other issues is a matter of the future.
CONTENT: Concepts of modern natural science
See also:...ideas about the origin and evolution of the solar system.... planetary systems are formed in a single process, as a result of cloud compression.our Solar system is almost the only one in the Galaxy, and man's search for intelligent life in the solar system does not exist in the Solar system was awakened only at the turn of the nama of the origin of life and its spread in the Solar system.
Astrophysics.
Stars and nebulae.
The solar system.
It is hoped that on the basis of these data, a more accurate answer to the question of the origin of the Solar system will be obtained.
The origin of oil coal and natural gas.
The origin of natural... the origin of oil and natural gas.
Oil and natural gas consist mainly of other chemical elements associated with the Sun, with the emergence of the solar system.
The mysteries of the Solar System.
Astronomers are perplexed The solar System is a creation of the mind?
Is the moon an artificial satellite?
Let us turn, however, to the arguments testifying to the "unnatural" origin of the Moon.
The origin of the planets.
Hypotheses of Kant, Laplace and Jeans.
Spectral... of historical interest.
As already mentioned, there is 98% of the moment of the amount of motion in the solar system.
it belongs to the planets and only 2% to the Sun.
Astronomical observations.
As for our solar system, its various artificial origins are dominated by nodes with four converging lines, and the network of channels of Mars has...
ASTRONOMY Spatial velocities of stars and the motion of the solar system.
Cosmogonic problems.
The origin and evolution of stars.
The structure of the solar system.
Careful scientific research has given ... the Solar system includes: The Sun, which is the dynamic center of the whole.
systems, 9 major planets, 32 satellites of planets, more than 1800 minor planets or.
SOLAR HEATING.
Passive solar heating systems There are active and passive solar heating systems.
Solar heating is most effective when...
