Question

What is the lower part of the thermosphere called?​

Answer 1

Answer:

The boundary between the thermosphere and the exosphere above it is called the thermopause. At the bottom of the thermosphere is the mesopause, the boundary between the thermosphere and the mesosphere below.

Explanation:

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Answer 2

Answer:

The lower part of the Thermosphere, a layer of ionised air extending from the Mesopause to approximately 600km is also known as the Ionosphere, while the upper part of the Thermosphere is also known as the Exosphere.

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