THERMOSPHERE AND MESOPAUSE. Among the 1000 km (600 miles) and 500 km (300 miles) of altitude below the. exosphere is the “thermopause” or “exobase” on top of the “thermosphere” and its. altitude varies with the solar activity.

Answer:

1. The thermopause is the atmospheric boundary of earth energy system
2. The mesopause is the point minimum temperature at the baundary between mesosphere