Enhanced acetylene emission near the north pole of jupiter

Abstract

We report observations of acetylene emission lines near 13.3 [mu]m on Jupiter recorded at the NASA Infrared Telescope Facility in July 1984. A strong enhancement in the intensity of R10 line of the [nu]5 band was recorded within a well-localized region coincident with the southern extension of footprint of the Io magnetic lines and with previous observations of localized enhanced emission of CH4 lines. The line intensity was fairly constant outside this "bright spot." Moreover, weak lines of the hot bands 2[nu]5 - [nu]5, and ([nu]4 + [nu]5) - [nu]5 were observed within the bright spot. From the field of view and the precision of the pointing, the zone of activity of the bright spot is found to be: latitude = 59 +/- 10[deg] and longitude = 178 +/- 10[deg] (System III, 1965). The location of the spot was found to be constant over a 3-day period. Two interpretations are proposed to explain these observations: (1) a variation of the C2H2 abundance and (2) an alteration of the thermal profile in the bright spot. Either may result from precipitation of charged particles near and below the Jovian homopause.