Models of thermospheric sodium, calcium and magnesium at the magnetic equator

摘要: Abstract In attempting to interpret recent observations of metals in the lower thermosphere, we have developed several comprehensive models. These models explicitly include deposition metal atoms from ablation cosmic dust, time-dependant chemical reactions, and transport both by diffusion electric fields. The modeling presented here focuses on depletion mesospheric column density calcium relative sodium neutrals, which is also observed thermospheric measurements. an effort obtain measured abundances, examine consequences differential oxides comprising dust. model, assumed come off first while less volatile magnesium remain liquid form be ablated later at somewhat altitudes. Model results show a strong dependance initial velocity dust particle, with “average” reproducing measurements quite well.