LAUSR

Jupiter's ultraviolet auroras are dominated by the main auroral oval, an almost continuous narrow band or series of bands of emission encircling the magnetic poles of the planet (e.g., Clarke et al., 2004; Grodent et al., 2003). This emission maps to the middle magnetosphere, and is generally believed to be driven by the breakdown in corotation of iogenic plasma at radial distances of several tens of planetary radii (Cowley & Bunce, 2001; Hill, 2001; Southwood & Kivelson, 2001). While the overall morphology of the main emission is fixed in System-III longitude and is relatively stable over observation timescales (Clarke et al., 2004), there also exist more dynamic features known to develop over timescales of minutes to tens of minutes. An example of these dynamic phenomena is dawn storms, a brightening of the main emission fixed at dawn. These events produce the most powerful auroral emissions observed at Jupiter and are likely associated with significant reconfigurations of the magnetosphere, but the precise mechanisms of their generation and evolution are currently unknown.