It is the only planet in the solar system that is known of the existence and the origin of life. It also has the unique feature that water is in a liquid state.

The Earth was formed 4,570 million years at the same time as the solar system. Its distance from the Sun is about 150,000 km, which is equivalent to the so-called Astronomical Unit (AU).

Composition of the Earth

It is a rocky planet in part by what comprises a multitude of rocks and minerals with various antiques. It is divided into the following sections depending on the model geostático:

·  Crust: it is the most superficial layer of the Earth and is in contact with the atmosphere. His limited to the mantle called the discontinuity of Mohorovicic. It is divided into two:

- Continental Crust: a crust formed by rocks from different backgrounds. It is found both in areas emerged as the submerged. It is thicker and more dense the ocean.

- Oceanic Crust: located in the submerged surface of the Earth. It is finer and less dense that the mainland. It consists mainly of basalt.

·  Manto: is the layer below the crust and reaches the heart. It consists mainly of silicate. They can differentiate the upper and lower mantle.

·  Core: is the deepest layer of the Earth is the center. It is a circle the size of Mars. The boundary with the cloak is called discontinuity Gutenberg.

The Atmosphere

The Earth also has formed a layer of gases that surrounds known as Atmospheric Administration. This layer absorbs heat emitted by the Sun for more heat during the day than by night.

The atmosphere is divided according to the proximity to the Earth:

·  Troposphere: is the layer closest to the Earth. Its area extends from the ground to an average of 12 km. As altitude increases the temperature decreases.

The boundary with the stratosphere is called Tropopause. In this area of the atmosphere where weather phenomena take place.

·  Stratosphere: it is the layer that follows the troposphere. It stretches from the 15 km in height from the ground up to 50 km where the Estratopausa, which is the highest area of the Stratosphere.

Unlike the case with the troposphere as altitude increases also rising temperature. This is because the ozone absorbs sunlight.

·  Mesosfera: is the third layer of the atmosphere in which both altitude increases the temperature was falling rapidly. Its border with Termosfera is Mesopausa.

Approximately extends from 50 km to 80 km from the ground. It is characterized by irradiation and chemical reactions that occur in it.

·  Termosfera: it is above the mesosphere. In layer is the temperature increases at a time that makes the altitude due to the absorption of solar radiation.

It is the place where auroras occur that are bright spots or columns in which one can observe various colors. The Termosfera can also receive the name of Ionosphere.

·  Exosfera: is the last layer of the atmosphere and is in contact with outer space. Arguably it is the outer limit of the Atmosphere.

In this region, the magnetic pull is greater than the gravitational so that the molecules and particles can escape into space without being attracted by gravity.