Which atmospheric layer is known for having the highest temperatures but is not breathable?

The thermosphere is known for having the highest temperatures among the layers of the Earth's atmosphere. This layer extends from about 85 kilometers (53 miles) above the Earth's surface up to 600 kilometers (373 miles) or more. The temperatures in the thermosphere can reach up to 2,500 degrees Celsius (4,500 degrees Fahrenheit) or even higher, primarily due to the absorption of intense solar radiation by the few gas molecules present.

Despite these high temperatures, the thermosphere is not breathable for humans. The air is extremely thin, and there is not enough oxygen available to support life. The low density of the atmosphere in this layer makes it largely inhospitable and unbreathable, even though the temperature readings are very high. This combination of extreme temperature and very sparse air is why the thermosphere is distinct from the other layers of the atmosphere.