Temperatures rise rapidly with altitude in the lower thermosphere. Higher up, the temperature stays constant across altitudes. However, the hottest temperature in the thermosphere varies a lot between day and night and between the minimum and maximum of solar activity. Click on image for full size (24 Kb) Images courtesy of The COMET Program and HAO at NCAR (modified by Windows to the Universe staff).

Temperatures rise rapidly with altitude in the lower thermosphere. Somewhere above an altitude between 200 and 300 km (about 320 to 480 miles) the temperature stays pretty much constant across altitudes. However, the hottest temperature in the thermosphere varies a lot between day and night and between the minimum and maximum levels of solar activity during the Sun's 11-year sunspot cycle.

At first, the temperature gets warmer very quickly as you go upward in the thermosphere. After that, the temperature doesn't change much as you go higher. However, the hottest temperature changes between day and night. It also depends on whether the Sun is active (solar max) or not (solar min). Click on image for full size (24 Kb) Images courtesy of The COMET Program and HAO at NCAR (modified by Windows to the Universe staff).

At first, the temperature gets warmer very quickly as you go upward in the thermosphere. After that, the temperature doesn't change much as you go higher. However, the hottest temperature changes between day and night. It also depends on how active the Sun is during its 11-year sunspot cycle. The thermosphere is hottest when the Sun is very active during "solar max". It isn't quite so hot when the Sun is less active during "solar min".

At first, the temperature gets warmer very quickly as you go upward in the thermosphere. After that, the temperature doesn't change much as you go higher. However, the hottest temperature changes between day and night. It also depends on whether the Sun is active (solar max) or not (solar min). Click on image for full size (24 Kb) Images courtesy of The COMET Program and HAO at NCAR (modified by Windows to the Universe staff).

At first, the temperature gets warmer very quickly as you go upward in the thermosphere. After that, the temperature doesn't change much as you go higher. However, the hottest temperature changes between day and night. It also depends on how active the Sun is during its 11-year sunspot cycle. The thermosphere is hottest when the Sun is very active during "solar max". It isn't quite so hot when the Sun is less active during "solar min".