[3] Progress of Jupiter's great northern upheaval 2012 July-August.

Jupiter in 2012/13: Interim report no.3 (2012 Sep.20)

Progress of Jupiter’s great northern upheaval, 2012 July-August.

John Rogers (BAA) & Gianluigi Adamoli (JUPOS team)

In 2012, Jupiter is displaying the unprecedented spectacle of two simultaneous great outbreaks in adjacent domains, comprising revivals of the NEB and NTB.  Both started just before solar conjunction and largely developed during that period of invisibility, but spectacular disturbances were evident when the planet reappeared in June [Ref.1].  Now, with improved images as the planet rises higher, and with charts and maps from the JUPOS team, we have a clearer picture of what has been happening.  This report covers July and early August. At the time of writing, in late August, the disturbed regions seem to be settling down.  So, although further results may yet emerge, this may stand as our main report on these disturbances which are unprecedented in modern times.

This report is arranged so that the main text is largely overviews and discussion, with specific details given in the Appendix (Notes 1-6) and Table 1. Maps of the northern hemisphere throughout July are aligned in Fig.1, and a more recent map of the whole planet is Fig.2.  Images in the ultraviolet and infrared, along with  latitude measurements in different wave-bands, are given in the accompanying Report no.4.

The NEB is indeed undergoing a full-scale revival for the first time since 1926, and the NTB is indeed reviving via a super-fast jet-stream outbreak as last seen in 2007.  Sectors of the belts and the intervening NTropZ which were still light in June have now filled in with intense turbulence and reddish (ochre or orange) colour, producing one vast brown-and-ochre belt from the NEBs to the NTB.  Large eruptions seem to be finished, and as usual in such events, the disturbance has evolved from larger to smaller scales, so by the end of July the whole region was filled with small streaks.  These formed a remarkable herring-bone pattern across the whole region in hi-res images, displaying the wind gradients.  Flanking domains are also affected:  The NNTB has virtually disappeared, while there is an ochre Equatorial Band stretching half way around the equator. 

The full report including figures is available at the link below:

LINK TO ZIP FILE OF COMPLETE REPORT INC FIGURES.

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John H. Rogers, Ph.D. Jupiter Section Director,
British Astronomical Association
jhr11@cam.ac.uk
http://www.britastro.org/jupiter/