Thermosphere gas and the ionospheric plasma. The International Space Station orbits the Earth within the middle of the thermosphere, between . It is convenient to separate the atmospheric regions according to the two temperature minima at about 12 km altitude (the tropopause) and at about 85 km (the mesopause) (Figure 1). The thermosphere (or the upper atmosphere) is the height region above 85 km, while the region between the tropopause and the mesopause is the middle atmosphere (stratosphere and mesosphere) where absorption of solar UV radiation generates the temperature maximum near 45 km altitude and causes the ozone layer. The density
Thermal radiation the sun. For instance, when a green house is made, most of the roof and walls are made out of glass. Glass is transparent in the visible (approximately 0.4 µm<λ<0.8 µm) and near-infrared wavelengths, but opaque to mid- to far-wavelength infrared (approximately λ>3 µm). Therefore, glass lets in radiation in the visible range, allowing us to be able to see through it, but does not let out radiation that is emitted from objects at or close to room temperature. This traps what we feel as heat. This is known as the greenhouse effect and can be observed by getting into