Definition of Mesosphere
Mesosphere is a layer of Earth’s atmosphere that is present directly above the stratosphere and below the thermosphere. The boundary that is present between the mesosphere and the thermosphere is called mesopause and that between the mesosphere and stratosphere is known as stratopause. The presence of this layer is estimated to be 50 to 85 kilometres above the Earth.
As the height increases, the temperature of the mesosphere starts to drop. The temperature at the top of the layer is lowest and it is -90 degrees celsius. It is still very difficult to study the mesosphere as no air balloon can fly up to there and satellites are unable to determine its characteristics as they orbit above it.