Emm, i have a question on the formation of the earth atmosphere.
how exactly was the earth’s atmosphere formed in a chronological sense? why was such a formation unique in that we do not observe other planets with similar atmospheric features?
provide reference would be better, .

Evolution of Atmosphere

Explanation:

The first atmosphere consists of gases in solar nebular, Primarily hydrogen-like found in gaseous planets like Jupiter, Saturn and notably water vapor. This was characterized as the primary atmosphere of the earth. The secondary atmosphere was formed by the outgassing from volcanoes, supplemented by the bombardment of the asteroid, carbon dioxide and nitrogen gases i.e about 3.4 billion years ago.  In the late Archean period oxygen-containing atmosphere was developed some 2.7 billion years ago. The third,  atmosphere was due to the constant rearrangement of plate tectonics influencing the long term evolution of the atmosphere, the amount of oxygen in the atmosphere was fluctuating around 600 million years ago. After which the atmosphere came to be divided into various zones such as the Tropos, Stratos, Mesos, Thermos, and Exosphere.  Such formation was unique as the earth is close to the sun and solar storms drove away much of the gases and regular heating and cooling lead to the formation of the earth what it is today.  

Round it to the nearest tenth