Observational trends of the Jovian UV aurora, obtained from the Goddard High Resolution Spectrograph(GHRS) on board the Hubble Space Telescope(HST), are explained by a simple two component model. The model consists of cool and warm components with temperatures of about 400 and 1000K, and with methane absorptions corresponding to column densities of 6-9e16/cm2 and no methane absorption, respectively. Three trends that (1) brighter UV spectra have lower temperatures, and (2) spectra with stronger methane absorption show lower temperatures, and (3) spectra with stronger methane absorption seem to be brighter, are accounted by combinations of two components with various filling factors and intensity ratios. The model implies that precipitating particles responsibie for the cool component have higher individual energy and stronger energy flux than those for the warm component. Estimation of GHRS aperture location on UV auroral images taken by the Wide Field Planetary Camera 2(WFPC2) suggests that the cool component may correspond to emission along the oval, and the warm component to diffuse features of UV emission. Preliminary comparison of images by the WFPC2 and those by H3+ 4 micrometer ground-based observations implies that the warm component causes both weak diffuse features of UV emission and bright H3+ emission in an area at lambda III - 150 deg. inside the northern oval.

• KIM YONG HA(Department of Astronomy and Space Science Chungnam National University)