Earth :

    It is the only planet known to scientists that can support life, thanks to the water in its oceans and the oxygen contained in its atmosphere.       
    In contrast to "Neptune" (extremely galcial), and "Mercury" (intensely hot), the Earth is located at an ideal distance from the sun.
    For its size, the Earth is very heavy because of the iron contained in its core.
The stirring movement of liquid iron generates a powerful magnetic field, which forms a shield that protects the Earth from dangerous solar particles. Earth's atmosphere also functions as a shield against deadly radiation from the sun                    The Earth is not a solid ball; it is made of different layers; its surface is a thin shell of solid rock: the crust that forms the continents and the bottom of the oceans   The heat released by its core to the surface pushes sections of the crust (called tectonic plates); this phenomenon modifies or creates most of the natural characteristics of the Earth.

The Terrestrial Atmosphere :

    Water covers 70% of the earth's surface ; they contribute to a moderate temperature on Earth and release water vapor in addition to other gases which envelop the Earth forming our atmosphere. Furthermore, whirlpools of white clouds, carried by the winds, move constantly.
   From space, the continents appear dark, green or brown, and the oceans blue.

      >>In this picture, most of the Middle East is cloudless; the deserts of North Africa    and the Arabian Peninsula are clearly visible.

A waterlogged planet! 

    On Earth we fear to find water in different forms:  liquid ( rain, lakes, rivers,... ) ,  gaseous ( water vapor ) , and  solid ( ice ).  It is she who makes life on Earth possible.

The mountain ranges:

    Generally, large mountain ranges have been formed by the meeting of 2 tectonic plates : upon colliding, one of them was forced to rise.
    In the Himalayan Ranges, Mount Everest is the highest peak above sea level, however the volcanic island Mauna Loa in Hawaii is the highest on Earth, as measured from its height, base at the bottom of the ocean, up to its highest point.

Life in extravagance :

    Life exists almost everywhere on Earth, from the highest mountains to the deepest caves. It is not known how many living species inhabit the planet, but there are millions of them.

   Indeed, the first form of life appeared in the oceans about 4 billion years

 ago ; whereas animals began to evolve only about 600 million years ago, while the current human being only appeared 100,000 years ago.

Volcanoes and Earthquakes:

    Living in a tectonic plate junction area can be dangerous. Most earthquakes occur when plates collide or slide over each other. In some cities like San Francisco, the great earthquakes produced more energy than an atomic bomb!

    In addition, volcanoes erupt as molten rock rises to the surface, spreading lava and ash over vast areas.