Thermosphere

The thermosphere is a layer of the Earth’s atmosphere extending roughly from 85 km to 600 km above the surface. In this region, air density is extremely low, but solar radiation strongly heats the sparse gas particles, causing temperatures to rise significantly with altitude. Variations in thermospheric density, driven by solar and geomagnetic activity, directly affect the atmospheric drag experienced by low Earth orbit (LEO) satellites. Accurate modelling of the thermosphere is therefore essential for precise orbit determination and prediction of satellite trajectories.