What is atmosphere and what is composition and structure of atmosphere?

Answer 1

It is the all kind of gaseous layer which is covered the earth. It is the essential part on earth for life, without this atmosphere life on earth isn't possible. It gives us air, water, warmth and is protecting us against harmful rays of the sun and against meteorites. This layer around the earth is a colourless, odourless, tasteless 'sea' of gases, water and fine dust. The atmosphere is made up of different layers with different qualities. It consists of 78% nitrogen, 21% oxygen, 0.93% argon, 0.03% carbon dioxide and 0.04% of other gases. The Troposphere is the layer where the weather happens; above this layer is the Stratosphere. Within the Stratosphere is the Ozone layer that absorbs the Sun's harmful ultraviolet rays. Above the Stratosphere is the Mesosphere, the Thermosphere - in which the Ionosphere - and the Exosphere. The atmosphere is about 500 miles (800 km) thick.