Auroral hot spots are observed across the Universe at brown dwarfs, X-ray pulsars, magnetars and planets. Within our own solar system, Jupiter possesses the only spatially resolvable example of these widespread phenomena. Jupiter’s Northern X-ray aurora is concentrated into one of these polar hot spots, which is characterised by spectral lines of precipitating ~MeV/amu ions and pulsates on timescales of several 10s of minutes. This hot spot is located in the most poleward regions of Jupiter's multi-waveband aurora, where magnetic field lines map to the noon-dusk magnetopause . Given this mapping, the hot spots may be expected to be diagnostic of Jupiter's relationship with the solar wind and they do indeed change morphology, intensity and precipitating particle populations with changing solar wind conditions.
We present XMM-Newton and Chandra X-ray observations from Summer 2016 (during Juno approach) and Spring 2007 (during New Horizons approach), when the observing geometry provided good visibility of Jupiter’s South Pole. These observations reveal that Jupiter’s Southern X-ray aurora also appears to be concentrated into a persistent hot spot. However, X-ray timing analysis suggests that, for these observations, Jupiter’s Northern and Southern polar X-ray aurora behave independently.
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