SOLAR SYSTEM

Detailed explanation-1: -Earth’s second atmosphere, 2.5 billion years ago, was formed when Earth’s crust started to cool down and the amount of water vapor in the atmosphere decreased, as water started condensing in liquid form.

Detailed explanation-2: -About 2.5 billion years ago, the second atmosphere on earth was the first to stay on the planet, it formed form volcanic outgassing and comet ices. This atmosphere was composed of water vapor, carbon dioxide, nitrogen and methane with almost no oxygen.

Detailed explanation-3: -In fact scientists think that 99% of today’s atmosphere is new compared to the original air. Thus scientists call the atmosphere of today a secondary atmosphere. Scientists think that the secondary atmosphere came from the many volcanic eruptions which took place in Earth’s early history, and which continue today.

Detailed explanation-4: -How did the process of outgassing help shape Earth’s atmosphere? During outgassing, volcanoes released large amounts of gases into the air. These gases included water vapor, carbon dioxide, nitrogen, methane, sulfur dioxide, and ammonia. The gases then became part of the atmosphere.