On the zenith angle dependence of the infrared oxygen emission of 1.27 μm airglow observed from high altitude

In recent years the 1.27 μm band emission in the night airglow is observed extensively. The emission belongs to the infrared atmospheric system of oxygen. In the present work the zenith angle dependence of the emission rate of the 1.27 μm airglow is examined with the data from a balloon-borne photometer. The calculated results are in agreement with the observed intensities except for a zenith distance larger than 800. Therefore, the intensity distribution of the infrared atmospheric band can be interpreted in terms of the absorption of the lower atmosphere. The deviation in the horizontal direction is possibly due to the re-emission of the 1.27 μm radiation absorbed in the lower atmosphere. (Mori, K.)