SPACE: solar system

 The solar system:

    The central star of the solar system, the Sun, is 99.9% of its total mass. The gravity force of the Sun attracts everything around it, including the eight planets and their 168 satellites. Planets move around the Sun along trajectories called orbits, while turning on themselves (on their axis of revolution) as they move.

 >>The four inner planets are globes of rocks and metals.

 >>The outer planets are huge globes of gas or liquid.

The sun:

    A huge ball of rotating luminous gas, the Sun is more than a million times larger than the Earth. It draws its energy from nuclear reactions that occur in its core, at temperatures up to 15 million degrees.

Mercury:

    This small planet, closest to the sun, is covered with craters. During the day, the surface is suffocating at 430°C, while the temperature drops to 170°C at night. One year on Mercury corresponds to 88 Earth days.

Venus:

    She’s the awful sister of Earth. Its size and structure are identical to those of the Earth, but the air is poisoned; its surface is far too hot to allow any form of life. The Venus revolution is so slow that its day is longer than its year!

The Earth:

    Our planet is the only known place in the Univners where life is found. Its oceans cover two-thirds of its surface. White clouds filled with water swirl through the atmosphere. ■The Earth has only one moon.

Mars:

     It was believed that there could be life on Mars as on Earth, there are mountains, canyons, frozen poles and an atmosphere. However, its surface is only an arid desert. Mars is about half the size of the Earth and has two satellites.

Jupiter:

    It is the largest planet in the solar system; it is heavier than all the other planets combined. It is a huge globe of liquid and gas surrounded by circular cloud strips. Jupiter has 63 satellites, four of which are larger than Pluto.

Saturne:

     If we could put the eight planets in a huge bucket of water, only Saturn would float; almost as big as Jupiter, but much lighter. Its rings are made of millions of sparkling particles of ice. Saturn also has 60 icy satellites.

Uranus:

    With its uniform blue surface, Uranus looks like a billiard ball. Four times larger than Earth, it is 20 times farther from the Sun and has 29 satellites. The one who discovered Uranus would have liked to call him "Star of Georgre".

Neptune:

    Neptune’s winds are the fastest in the solar system: they sweep over the planet at over 2,000 km/h. Its violent storms resemble very dark spots. Neptune resembles Uranus and has 13 satellites.

Pluto!

    For 76 years, this body was considered a planet, but on August 24, 2006, the General Assembly of the International Astronomical Union (UAI) decided, in Prague, to strip Pluto of its planet status, bringing to eight the number of planets in the solar system. This choice is due to the composition, size, and orbit of Pluto. Astronomers believe that Pluto is a satellite of Neptune or an object in the Kuiper belt. The final text of the UAI then made a distinction between planets, dwarf planets and small bodies of the solar system. Pluto is thus relegated among the dwarf planets.

    The trajectory of Pluto:

Pluto’s orbit, which has the shape of a sloping egg, brings it a few times closer to the sun than Neptune.

    comets!

Behind Pluto’s orbit, we observe a cloud of gigantic balls of light called comets. From time to time, one of them runs towards the Sun and then moves away from it again.