The solar system is one of many planetary systems in the vast galaxy of the Milky Way, but only it is more or less studied. In addition to her, there are more than one million star systems in the galaxy, about which we are not aware. Modern space exploration technologies make it possible to learn a lot of information about the structure and structure of the solar system, the location of the planets and their parameters, as well as about other celestial bodies that are in it. Now we know that in the center of it is the Sun, around which planets, including the Earth, rotate at different speeds under the influence of gravitational forces . A large proportion of the mass of the system falls on the Sun - almost 99.866%, and 99% of the rest of the mass is concentrated in giant planets.
It was previously assumed that there are 9 planets in our stellar system, but since Pluto was deleted from the list of planets in 2006, we can assume that there are 8 of them. Each of them rotates around the Sun in its own specific orbit, and all orbits are located in one ecliptic planes. They are conditionally divided into two groups. In the first are terrestrial planets, consisting mainly of iron ore and rock, these are Mercury, Earth, Venus and Mars. The arrangement of the planets of this group is close to the sun. Mercury and Venus have no satellites, Mars has two of them - Demos and Phobos, while the Moon moves around the Earth.
The planets of the second group are called giant planets due to the huge mass and volume that are several times higher than the indicators of the objects of the earth group. These are Uranus, Saturn, Jupiter and Neptune. They are gas, often composed of helium and hydrogen, and only Saturn has a solid core. The location of the planets of this type is such that their orbits are much farther from the Sun than that of the representatives of the first group. And another difference is the presence of a large number of satellites around these planets. For example, 63 satellites accompany Jupiter, there are 62 and several rings near Saturn, Uranus has 27, and Neptune - 13.
Mercury is closest to the Sun. Its orbit is only 57.9 million km from the star. The orbit of Venus is located a little further - at 108.2 million km. The third remotest is Earth. Its rotation path around the celestial body is located at a distance of 149.6 million km, which is optimal for the existence of life on the planet. In fact, there is life on our planet alone from the whole system. Mars, in comparison with other objects of the terrestrial group, is the most distant. Its orbit is the fourth - 227.9 million km.
The location of the giant planets is much farther from the Sun. Closest to all is Jupiter - the largest of all the planets in our star system. It rotates in its fifth orbit, 778.6 million km from the star. The sixth orbit on 1433.7 million kilometers is occupied by Saturn, which is in second place among the largest planets. Uranus moves in the seventh orbit, which is 2870.4 million km away from the Sun. And the most distant planet of all is Neptune. Its orbit is located at a distance of 4491.1 million km.
In many models, the location of the planets of the solar system is conventionally shown with equal intervals between the orbits of all the planets, but it looks a little different in reality. By and large, the distance between them increases proportionally with distance from the star.
The rotation of almost all planets occurs against the direction of clockwise movement, if observed from the North Pole, but Venus and Uranus are an exception. They move in the opposite direction. And Uranus still has an axis tilt of almost 90 °, which looks like it is lying on its side.
The location of the planets in the solar system and their mass largely affect the speed of their rotation around the sun. Mercury rotates faster than anyone - it makes a complete revolution around the luminary in 88 days (earthly days). And the slowest - Neptune - it takes 165 years to turn around.