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The radioactive gas and aerosol ejections during and after accident at the nuclear power-station are very dangerous source of environmental pollution. These ejections are spread by meteorological air flows above considerable distances (up to several thousands km and more). This radioactive cloud is gradually blown away, changing its form and density. Because of the air heating over the accidental place the radioactive cloud can rise up to 14 km (tropopause). Therefore the dissipation and settling of radioactive nuclides are occurred over very large area. In this paper the optical method of registration of radioactive air ejection by means of particular bands of atmospheric fluorescence with very high threshold of excitation due to Auger effect is presented. There are three emission bands which are quite prominent and lie in the blue range of spectrum (400-480nm). It is important that they are absent in other events of natural and technological air emissions, besides short time lightning. The intensity of these emissions is much higher than background, especially at night. The transformation ratio from y-radiation flux to the visual one (for three bands) is 10-1 - 10-2 and for large accident like in Chernobyl one the optical emission (for radioactive cloud of 106 Ci) could be approximately 1014 - 1015 photons·c-1. For remote sensing of the radioactive air ejection the filter radiometer should be recommended the filters corresponding to the wavelengths of the particular emission bands. In existing aerospace remote sensing experiments these filters still haven't been used. Keywords: nuclear power-station, accident, radioactive cloud, optical fluorescence, Auger effect
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