Mesophere

The atmosphere of earth is divided into five layers namely troposphere, stratosphere, mesosphere, thermosphere and exosphere. These layers protect the living creature of earth from the harmful radiations like UV light coming from sun. The five layers have individually different properties. Among them, mesosphere is described below.
Mesosphere is the third layer of the atmosphere situated at 50kms above the surface of the earth, between the stratosphere and thermosphere. Mesosphere literally means ‘middle sphere’. The mesosphere begins after stratopause: the transition region of stratosphere to mesosphere, and ends after the mesopause: top of the mesosphere and start of thermosphere. It plays an important role in protecting life on earth. The most important of mesosphere is the destruction of the meteors that fall on the earth. The meteors collides the gas particles present in mesosphere and burn. From earth, we call them the shooting stars. The troposphere layer is heated due to carbon dioxide gas and causes greenhouse effect. But in mesosphere, the carbon dioxide cools down as the heat is released from the mesosphere to space. Due to solar light, the methane gas is decomposed. The temperature of mesosphere is -90° C to -130°C. Due to the low temperature, reactions take place with the ozone layer and the water vapor and the formation of microscopic ice clouds occur. These clouds are named as noctilucent clouds. These clouds are seen during the sunset and are better seen from poles. This layer lies above the maximum altitude to enable aircraft movement and lies below the minimum altitude to enable orbital spacecraft movement.
At night, the complete darkness is also due to the five kilometers of deep sodium layer. The layer is located just below the mesopause and is made up of unbound non ionized atoms of sodium. This layer of sodium forms the nightglow. The nightglow is the light emitted from the earth’s middle atmosphere. There are strong winds blowing from the mesosphere. Due to a considerable change in the magnitude of temperature between the summer and winter poles, strong winds blow from north to south in the low mesosphere. It is exactly the opposite in the upper mesosphere as the temperature there is colder. East west air currents are also intense at the middle latitudes.
Till today, scientists know very less about this layer in comparision to other layers. This layer is hard to study due to the temperature difference. It can only be accessed through the sounding rockets. These are the research rockets and instrument carrying rockets that are designed to perform specific experiments. Scientists are still continuing their research on mesosphere layer.