Solar System

The Solar System is made of the Sun, and the objects that turn around it. It counts, among other things, eight planets, including the Earth, our planet, the third one.

Diagram of the Solar System (not in scale). From center to outer : Sun, Mercury, Venus, the Earth, Mars, the Asteroids belt, Jupiter, Saturn, Uranus, Neptune, and Pluto. A comet can also be seen at the left.

Objects in the Solar System

• Planets - great objects that turn around the Sun. There are eight planets in the Solar System: Mercury, Venus, the Earth and Mars, the smaller ones, made of rocks, are called terrestrial, telluric or rocky planets. Jupiter, Saturn, Uranus and Neptune, the greater ones, are called gas giants or Jovian planets.

• Dwarf planets - great objects (not necessary smaller than the planets), that turn around the Sun, but are part of clouds of objects, named "belts", such as the Asteroid belt or the Kuiper belt. Pluto, once said to be the ninth planet, is the most famous. Eris and Ceres are also dwarf planets.

• Asteroids (or meteoroids) - are smaller objects, that have no regular shape: they look like immense blocks of rocks in the space. Most of them form a vast group called the Asteroid belt. Other can have uncommon orbit around the Sun System and sometimes difficult to find them.

• Satellites - are various size object, that don't turn directly around the Sun, but around a planet, a dwarf planet or an asteroid.

• Comets - are objects made of ice and dust that turn around the Sun in a peculiar way, that seem to pass through the Sun System.

• Planet 9 - Scientists believe that there might be a ninth Planet due to the dwarf Planets beyond Neptune moving in unusual ways. So, a mini-neptune might exist having an orbital period of 18.520 years.

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