The universe always interested the Humanity. There is thousands of years, before trying to drill the mysteries, the Man observed the night sky to find a way in the time and the space thanks to stars, define the day alternation night and, the changes in moon phases … But the position of planets almost immediately caught its attention. Nevertheless, in older times, the Man considered only the divine intervention as valid explanation of the laws of the universe and did not take into account the reasonings of the scientists which tried to understand and to explain what surrounded them. Today still, the men try to find their place in this vast universe.
The Earth is the only planet known which shelters life, it is also the third planet the closest to the Sun and the fifth biggest of the solar system.
The solar system is consists of the sun, the planets, the satellites...
A galaxy is a set of stars and a set of interstellar material. The cohesion of the material is assured by the gravitation.
The universe is a set of all which can exist it consists of planets, galaxies, billion billion stars...
You can see thanks to this video to what extent the Man is small...