The solar system only one of really incalculable number of the star worlds inhabiting the galaxy. A body of a system central and most considerable in every respect is the Sun. Around it on circular orbits 8 planets move. Quite so, them 8, but not 9 as was considered earlier. In 2006 the General Assembly of the International Astronomical Union carried Pluto to a new class of dwarf planets. So what celestial bodies inhabit the Solar system and in what order they are located?
Instruction
1. Most closer planets of terrestrial group are disposed to the Sun. Them is 4 - Mercury, Venus, Earth, Mars – in such order they are located concerning the Sun. Planets of terrestrial group have the small sizes and masses, have considerable density, and have a firm surface. Among them Earth has the biggest weight. These planets have the similar chemical composition and the identical building. In the center of everyone there is an iron kernel. Venus has it firm. At Mercury, Earth and Mars some part of a kernel is in the melted state. Above the cloak which external layer is called bark follows.
2. All planets of terrestrial group have magnetic fields and the atmospheres. Density of the atmospheres and their gas structure significantly differs. For example, Venus has the dense atmosphere consisting mostly of carbon dioxide. At Mercury it strongly discharged. A lot of light helium which Mercury receives from solar wind is its part. Mars also has quite relieved tension for 95% consisting of carbon dioxide. The earth has a considerable atmospheric layer as a part of which oxygen and nitrogen prevail.
3. Only 2 planets of the first four – Earth and Mars – have natural satellites. Satellites are the space bodies rotating around planets under the influence of gravitational forces. At Earth it is the Moon, Mars has Phobos and Deymos.
4. The second group - giant planets – are located behind an orbit of Mars in the following order: Jupiter, Saturn, Uranium and Neptune. They much more and massivny planets of terrestrial group, but it is strong – by 3-7 times – concede to them on density. Their main difference consists in lack of firm surfaces. Their extensive gas atmosphere as approaching the center of the planet is gradually condensed and also gradually turns into liquid state. Floodlight has the most considerable atmospheric layer. The atmospheres of Jupiter and Saturn contain hydrogen and helium, Uranium and the Neptune – methane, ammonia, water and an insignificant part of other connections.
5. All giants have small – concerning the sizes of the planet – a kernel. In general - their kernels surpass in the size by any of planets of terrestrial group. It is supposed that the central regions of giants represent a layer of hydrogen which under the influence of the high pressure and temperatures gained properties of metals. For this reason all giant planets have magnetic fields.
6. Giant planets have a large number of natural satellites and a ring. Saturn has 30 satellites, Uranium 21, Jupiter 39, the Neptune 8. But only only one Saturn has the rings, impressive by the size, consisting of the small particles rotating in the plane of its equator. At the others they are hardly noticeable.
7. Behind an orbit of the Neptune the Kuiper belt including poryadka70 000 objects which also Pluto is among is located. Further there is recently opened Erida who is moving on strongly extended orbit and settling down concerning the Sun is 3 times farther than Pluto. Today 5 celestial bodies carried to dwarf planets are known. It is Ceres, Pluto, Erida, Haumea, Makemake. It is possible that over time this list will be replenished. By estimates of scientists only in the Kuiper belt about 200 objects can be qualified as dwarf planets. Outside a belt their quantity increases till 2000.