Eight planets in the solar system

The solar system is a celestial system composed of the sun, planets and their satellites, asteroids, comets, meteors and interplanetary matter, and the sun is the center of the solar system. In the huge solar system family, the mass of the sun accounts for 99.8% of the total mass of the solar system, and the proportion of nine planets and tens of thousands of asteroids is very small. They have been running around the sun along their own orbits for ages, and at the same time, the sun has generously and selflessly contributed its own light and heat, warming every member of the solar system and promoting their continuous development and evolution.

In this family, the planet closest to the sun is Mercury, followed by Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Only five stars can be seen by the naked eye. The names of these five stars are different in different countries. There was a theory of five elements in ancient China, so the five elements of gold, wood, water, fire and earth were used to name Venus, Jupiter, Mercury, Mars and Saturn respectively. This is not because there is water on Mercury and trees on Jupiter. On the other hand, Europe calls Roman mythical figures by their names. The three distant planets discovered in modern times are called by the names of the gods of the sky, the ocean and the earth according to the tradition of naming mythical figures in the west, and are correspondingly translated into Uranus, Neptune and Pluto in Chinese.

The nine planets and the sun are the sun, Jupiter, Saturn, Uranus, Neptune, Earth, Venus, Mars, Mercury and Pluto in descending order. According to the standards of mass, size, chemical composition and distance from the sun, it can be roughly divided into three categories: terrestrial planets; Giant planets (Jupiter and Saturn); The distant planets Uranus, Neptune and Pluto. They are coplanar, isotropic and almost circular when they rotate. There are hundreds of thousands of asteroids of different sizes and shapes between Mars and Jupiter. Astronomy calls this area the asteroid belt. In addition, the solar system also includes many comets and countless whispers-meteors.

Mercury is 58 million kilometers.

Venus 108 000 000 km

The earth is150,000,000 kilometers.

Mars is 228 million kilometers long.

Jupiter is 778 million kilometers.

Saturn 1 427 000 000 km

Uranus is 2.87 billion kilometers.

Neptune is 4.497 billion kilometers.

(Pluto 5 9 14 000 000 km)

Astronomical unit:1.500 million kilometers The earth to the sun is regarded as an astronomical unit (AU).