Since the twentieth century, space has been actively explored by people. Although the ancients also knew enough about the luminaries, planets, comets. Celestial objects have always attracted the close attention of man.
About 4.5 billion years ago, a system was formed in which the planet Earth - the Sun is located. The main object of the system is the Sun star. Approximately 99% of the total mass of the system falls on this star. And only 1% falls on the remaining planets and objects. At the same time, 99% of its remaining mass is the giant planets.
The giants of the system include Jupiter, Saturn, Uranus, Neptune. Jupiter is the largest of the planets. Its mass is about 318 times the mass of the Earth. And if you put together all the other planets, then its mass exceeds the mass of these planets by 2.5 times. It is characterized by two main components: hydrogen and helium. Jupiter is famous for a large number of satellites. He has 65 of them. Moreover, the largest, Ganymede, is much larger than the planet Mercury. Also, Jupiter's satellites are similar in some respects to the terrestrial planets.
Saturn is well recognized by the ring system. Takes second place in the group of "giant planets". 95 times heavier than Earth. The composition of the planet resembles Jupiter, but has a very low density, which is similar to the density of water. Saturn has 62 moons. Titan is the only moon in the solar system that has a substantial atmosphere.
The third largest planet is Uranus, the lightest of the outer planets. Its mass is 14 times greater than that of the earth. It is noteworthy that Uranus revolves around the Sun "on its side". He seems to be rolling in his orbit. It radiates a huge amount of heat into space, moreover, it has a colder core than other gas giants. Has 27 satellites.
Next in size, but not in mass, the planet is Neptune. The mass of Neptune is 17 Earth masses. It is denser, but does not radiate as much heat into space as, for example, Saturn or Jupiter. Neptune has 13 satellites (which are known to science). The largest is Triton. There are geysers of liquid nitrogen on it. Triton is moving in the opposite direction and is accompanied by asteroids.
Giant planets have their own characteristics. The time of their revolution around its axis does not exceed eighteen hours. And they rotate unevenly - in layers. The equatorial belt rotates the fastest. This circumstance is due to the fact that these planets are not solid, and at the poles they are compressed much more densely. The basis of Jupiter and Saturn is helium and hydrogen, Uranus and Neptune contain ammonia, water and methane.
Giant planets: interesting facts
1. Gas giants are planets without a surface. The gases of their atmospheres condense towards the center, turning into a liquid.
2. In the center of the giants there is a dense core, which, according to scientists, contains hydrogen with metallic properties. This hydrogen conducts electricity, giving the planets a magnetic field.
3. Almost all natural satellites of the solar system belong to the planets of this group.
4. All planets in this group have rings. But only Saturn has pronounced rings, while the rest of them are insignificant and barely distinguishable.
