Question

Why can’t planes fly in the mesosphere?

Answer 1

Hint: The mesosphere is the layer of atmosphere that lies above the stratosphere. Hence not much has been studied about the layer by meteorologists. And it is the coldest part of the atmosphere and it is much higher than our planet.

Complete Step By Step Answer:
Mesosphere-
Meso means middle and it is the highest layer of the atmosphere in which the gases are all mixed up arter than being layered by their mass. Mesosphere is a layer of earth’s atmosphere. It extends from about $50$ to $85$ km above our planet. It begins at the top of the stratosphere and ends at the mesosphere which is the coldest part of Earth’s atmosphere with temperatures below $-{143}^{\circ }C$ . Hence the mesosphere is directly above the stratosphere and below the thermosphere. The temperature decreases with height throughout the mesosphere.The temperature decreases cold enough to freeze water vapour in its atmosphere into ice clouds and this cloud is called noctilucent clouds or polar mesospheric clouds. These clouds are more visible at sunset from the earth’s pole. It is $22miles$ thick. The air is still thin so we cannot breathe and sustain life in the mesosphere.
In short we can say it is very cold,the air in the mesosphere is very thin and it is the highest layer and very far away from our planet hence it is very difficult to survive in this layer.
We conclude that planes cannot fly in the mesosphere.

Note:
Remember also the plane can't fly in the thermosphere. Another important point in this problem is that not only plane weather balloons as well as satellites are also not able to fly in this layer of atmosphere called Mesosphere.