Final answer:
The thermosphere has two significant sub-layers: the lower thermosphere, where temperatures rise with altitude and satellites orbit, and the ionosphere, which is crucial for radio communication and reacts to solar conditions.
Step-by-step explanation:
Subcategories of The Thermosphere
The thermosphere is one of the upper layers of the Earth's atmosphere, sitting just above the mesosphere and below the exosphere. Within the thermosphere, there are two distinct sub-layers that are significant for different reasons: the lower thermosphere and the ionosphere.
Lower Thermosphere
The lower thermosphere extends from about 85 kilometers (53 miles) to around 600 kilometers (372 miles) above the Earth's surface. In this layer, the air is thin, temperatures rise sharply with altitude due to the absorption of intense solar radiation. Satellites orbit in this layer, and it's also where the mesmerizing auroras occur, which includes both the aurora borealis (Northern Lights) and aurora australis (Southern Lights).
Ionosphere
The ionosphere overlaps with the mesosphere, thermosphere, and part of the exosphere, stretching from about 48 kilometers (30 miles) to the edge of space at approximately 965 kilometers (600 miles). It plays a crucial role in atmospheric electricity and is indispensable for radio communication, as it reflects and modifies radio waves for long-distance transmission. This layer changes in response to solar conditions, highlighting its importance in Sun-Earth interactions.