Energy distribution of fast nitrogen atoms in the nighttime terrestrial thermosphere

Energetic nitrogen atoms play a significant role in the chemistry and thermal balance of the thermosphere. The nocturnal energy distribution is calculated and the importance of including the center of mass motion is demonstrated. The center of mass motion gives rise to an extended component of fast atoms. The calculation of the energy distribution includes the loss of energetic nitrogen atoms in reactions with molecular oxygen. The density of energetic atoms and their energy distribution are strong functions of local time, altitude, and latitude.