The characteristics and the importance of the mesosphere layer
The mesosphere layer
The mesosphere layer is the third layer of the atmospheric envelope , It is the middle layer , It is the coldest one , The atmospheric pressure in the mesosphere layer decreases as we go up , until it becomes 0.01 mb , at its top .
The mesosphere layer extends from the stratopause ( at a height of 50 km above the sea level ) to the mesopause ( at a height of 85 km above the sea level ) . The thickness of the mesosphere layer is 35 kilometres .
The temperature in the mesosphere layer decreases with a rate as we go up until it reaches ( – 90 degree Celsius ) at its top . So , it is called the coldest layer .
The mesosphere layer contains limited quantities of helium and hydrogen gases only , So , It is highly rarefied .
The mesosphere layer protects the planet Earth from the celestial rocky masses that enters the atmospheric envelope of the Earth , where they burn as a result of their friction with the air molecules , And forming luminous meteors .
Although the meteors are burnt in the mesosphere layer , the spaceships can not burnt during their passing in it as their conical fronts disperse the heat and their tails are made of an insulated material .