How were the layers of the atmosphere discovered?
In the mesosphere, which extends to about 50 miles, temperature drops again to as low as -173 degrees F. Meteors, small pieces of matter drawn to the atmosphere by earth’s gravity, become visible to the naked eye as they enter the mesosphere and are heated through friction caused by collisions with air molecules. These “falling stars” usually disintegrate before they reach the earth’s surface. Spectacular meteor showers can be observed at certain times of the year when the earth, in its orbit, passes through a swarm of particles generated from the breakup of a comet. The troposphere, stratosphere and mesosphere make up what is called the lower atmosphere.
