What happens to temperature when you get higher than the mesopause?

Above the mesopause, in the thermosphere, temperatures begin to rise significantly with increasing altitude. This is due to the absorption of high-energy solar radiation by a sparse amount of gas molecules, which causes them to become energized. As a result, temperatures can reach up to 2,500 degrees Celsius (4,500 degrees Fahrenheit) or higher, although the thin atmosphere means that this heat would not feel warm to a human.