Dust particle charging and formation of dust structures in the upper atmosphere

We investigate the dust particle charging process in the Earth’s upper atmosphere. Calculating the spectra of solar radiation, we study the influence of the photoelectric effect on the charging process. We show that both positively and negatively charged dust particles are present in the upper atmosphere. We consider the mechanisms which can be responsible for the formation of dust structures like noctilucent clouds and polar mesosphere summer echoes.