How thick is the thermosphere?

The thermosphere is between 410 and 910 kilometers thick, depending on the location. The thermosphere is the thickest part of the atmosphere by far, and is the second highest layer, just underneath the exosphere.

The thermosphere is the main layer that is affected by the sun's ultraviolet radiation. The solar radiation is responsible for the thermosphere reaching temperatures of up to 2,000 degrees Celsius. The lower thermosphere is much cooler than the upper thermosphere. As expected, the thermosphere is warmer during the day than at night, with an average difference of about 200 degrees Celsius. The exosphere above is the final layer of the atmosphere, where air turns into space.