| Term: | mesosphere |
| Definition: |
The region of the Earth’s atmosphere between the upper limit of the stratosphere (approximately 30 km altitude) and the lower limit of the thermosphere (approximately 80 km altitude). |
| Term: | mesosphere |
| Definition: |
The mesosphere refers to the mantle in the region between the asthenosphere and the outer core. The upper boundary is defined as the sharp increase in seismic wave velocities and density at a depth of 660 km. [Wikipedia] |