Planets

Planets – It is derived from the Greek word “planodnos” – wandering, wandering.
According to the ancient definition given in ancient times, these are “wandering luminaries” that move against the background of fixed stars. Planets are cold, i.e. they do not emit light in the visible spectrum of electromagnetic radiation, but are light-reflecting cosmic bodies with a large mass that make a complete revolution around the Sun or other stars. To date, there are 9 large planets in the Solar System, located in order from the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto and many asteroids – small planets. The rules for determining the minimum sizes of cosmic bodies in which they are not yet meteoroids and are considered small planets have not been defined. See also the articles on the names of planets and the article Asteroids.
Planets observed without using a telescope (Mercury, Venus, Mars, Jupiter, Saturn, along with the Sun and Moon) – seven luminaries moving across the sky – have always attracted people’s attention. It was their number that influenced the fact that the week consists of seven days. Not only in the languages of the peoples of the world, the names of some days of the week have their lexical roots, but also in Russian, some of these days have the same names.
For more information about the planetary systems of other stars, see the article Stellar satellites, invisible.
Many people know that giants have
These planets are located in the Solar System in order from the Sun: Jupiter, Saturn, Uranus and Neptune. They are very similar to each other in size and mass, which are much larger than any planet in the group (see here). They make up 99.6% of the mass of all the planets in the Solar system. Giant planets have relatively close orbits to the Sun, but their chemical composition is more similar to the solar one than that of the terrestrial planets, which are further from our main star. Planets larger than Earth are surrounded by many moons and rings (see Rings of planets), which consist of small solids. Unlike the terrestrial type, giant planets have a significantly lower density compared to the planet of the terrestrial group. Their structures differ from those of the terrestrial planets in that their internal structures have significant differences. See also what is the starry sky and the satellites that are not visible.
A society from another planet
In the Solar System, these are Mercury, Venus and Earth, which are located in order from the Sun. They are distinguished from the giant planets by the fact that they have similarities in size, mass, structure and position in the Solar system. In addition, they are characterized by a relatively high density. The planet Pluto has some differences from the terrestrial planets, but for historical reasons it is not yet one of them. At the same time, like other planets of the Earth group, it was discovered in 1930, and explored only in the 90s of the XX century.