THE 2-MU-M POLAR HAZE OF JUPITER

High-resolution spectroscopy of the polar regions of Jupiter revealed the spectral characteristics of the polar haze and numerous CH4 absorption lines in the range 4200-4700 cm-1. We present model spectra, which were constructed including CH4 lines, hydrogen pressure-induced opacity, and haze layers. From comparison with the model, we conclude that for optically thin haze models the polar haze is located mainly between the pressure levels of 70 and 5 mbar, and for opaque haze models the top of the haze layers should be around the 15-mbar level. The polar haze is found to be widely distributed in the south and north polar region, and is not particularly associated with auroral activities. The 2-μm broad-band image of the polar haze is found to be very similar to that of an 8900-Å image. The reflectance of the haze increases almost linearly between 4200 and 4600 cm-1, maintains a flat value between 4600 and 4800 cm-1, and decreases rapidly from 4800 to 4900 cm-1. © 1991.