Chapter 21.2, Problem 21.2.2SR

Interpretation Introduction

Interpretation: The process of formation of aurora borealis and aurora Australis should be determined.

Concept Introduction:

Atmosphere: The atmosphere is defined as air that is layer of gases which surrounds the earth due to gravity of earth.

The earth atmosphere consists of layers such as thermosphere, mesosphere, stratosphere and troposphere depending on the temperature and its composition.

The different regions of atmosphere and their description are as follows:

Thermosphere:

It is the top most layers in atmosphere which has high temperature than all other layers present in atmosphere. The high temperature is due to the heat released by the reactions like continuous attack of ${\text{O}}_{\text{2}}{\text{, N}}_{\text{2}}$ and atomic particles by energetic species.

Mesosphere:

It is layer next to thermosphere that is the layer below the thermosphere. The increasing temperature for this layer with respect to decreasing height is due to the presence of less concentration of ozone and other gases in it.

Stratosphere:

It is found below the mesosphere layer in which the concentration of ozone and other gases are high. The increasing temperature for this layer with respect to increasing height is due to the presence of high concentration of ozone and other gases in it.

Troposphere:

The layer is below stratosphere layer and it is closest to the earth surface. It is the thinnest place which is responsible for all weather conditions since it contains almost all amounts of water vapor with it.

Aurora borealis: They are celestial lights found in northern hemisphere.

Aurora Australis: They are same as aurora borealis but found in southern hemisphere.

Visible Range: The electromagnetic radiation which range is about 390 nm to 700 nm is considered as visible since the human eye can able to detect this range.

UV Range: The electromagnetic radiation which range is about 100 nm to 400nm is regarded as ultraviolet region and they are shorter than the visible region.