Solar control on Jupiter's equatorial X‐ray emissions: 26–29 November 2003 XMM‐Newton observation

Abstract

[1] During Nov. [26][27][28][29] 2003 XMM-Newton observed soft (0.2 -2 keV) X-ray emission from Jupiter for 69 hours. The low-latitude X-ray disk emission of Jupiter is observed to be almost uniform in intensity with brightness that is consistent with a solar-photon driven process. The simultaneous light curves of Jovian equatorial X rays and solar X rays (measured by the TIMED/SEE and GOES satellites) show similar day-to-day variability. A large solar X-ray flare occurring on the Jupiter-facing side of the Sun is found to have a corresponding feature in the Jovian X rays. These results support the hypothesis that X-ray emission from Jovian low-latitudes are solar X rays scattered from the planet's upper atmosphere, and suggest that the Sun directly controls the non-auroral X rays from Jupiter's disk. Our study also suggests that Jovian equatorial X rays can be used to monitor the solar X-ray flare activity on the hemisphere of the Sun that is invisible to space weather satellites.

The independent pulsations of Jupiter’s northern and southern X-ray auroras

“…Jupiter's equatorial emissions are produced by solar photons that are fluoresced and scattered in Jupiter's atmosphere 38,40,41 . Lightcurves and PSDs from the Jovian equator on 24 May (DoY 145) and 1 June (DoY 153) (Supplementary figure 4) between -30° and 30° latitude demonstrate that the periodic behaviour is not present in the equatorial region and that there was not a significant variation in the solar X-ray output (e.g.…”

Auroral Processes at the Giant Planets: Energy Deposition, Emission Mechanisms, Morphology and Spectra

“…Elastic and fluorescent scattering of solar X-rays takes place in planetary atmospheres (and on moon surfaces), in such a way that the planetary disks are seen to mirror the solar X-ray variability, on short timescales and over the solar cycle (e.g. Bhardwaj et al 2005b;Branduardi-Raymont et al 2010).…”

Charge Transfer Reactions

“…Branduardi-Raymont et al 2004, 2007b, 2008Bhardwaj et al 2005b). They showed that the equatorial component is predominantly caused by scattered solar X-rays (Maurellis et al 2000;Bhardwaj et al 2005b;Branduardi-Raymont et al 2007b), similar to Venus and Mars, and indicated that charge exchange is the basic explanation of the polar component for X-ray energies below ∼ 2 keV, while bremsstrahlung of energetic electrons precipitating from the magnetosphere may be responsible for the X-ray emission at higher energies (Branduardi-Raymont et al 2004, 2007a, 2008. In contrast to the nonmagnetic planets, however, where the heavy ions are supplied by the solar wind, the heavy ions could also originate from the Jovian magnetosphere, by acceleration and subsequent additional ionization of ambient sulfur and oxygen ions in a field-aligned potential (Bunce et al 2004), as explored by , who considered the second possibility more likely.…”