Xuguang Cai

With the launch of the Global‐scale Observations of the Limb and Disk (GOLD) mission, spatial variations of the thermospheric composition (Σ O / N 2 ) and temperature can be investigated. In this work, we defined the hemispheric asymmetry indexes of thermospheric composition and temperature and investigated their local time (LT), latitude, and seasonal variations. For the first time, it is found that the hemispheric asymmetry of the thermosphere is weaker toward the duskside statistically. In addition, the hemispheric asymmetry of the thermosphere is found to be weaker toward lower latitudes, and the northern hemisphere has a longer duration with lower Σ O / N 2 and higher temperature.