JunoCam at PJ26

This is our report on the JunoCam images at Perijove-26 on 2020 April 10. Highlights were as follows:

–Spectacular cyclonic chaotic regions in most of the northern domains.

–A methane-band image of such a chaotic region inthe NNTB, showing that orange as well as white strips are at high altitude.

–A closeup of a white ‘bay’ in the NEBn, revealing enigmatic amorphous cloud texture.

–In the EZ, more widespread mesoscale waves than ever before seen by JunoCam, on an intricate background of pale ochre, white and blue-grey streaks.

–An excellent view of a very interesting sector of the S. Temperate domain, in which two long-lived structured sectors have just collided following oval BA, while a new structured sector may be arising preceding oval BA.  Features include STB segment A which is highly turbulent; the p. end of the STB Spectre which may have dissipated; and a new dark spot in the white STB, which is a cyclone with a reddish cloud cover.  Animations of maps will enable winds to be measured in all these structures.

–In the S4 domain, a bright outbreak in a pale reddish cyclonic oblong, a small-scale version of the STB Spectre in 2018.

–A high-amplitude wave in the S6 jet, coinciding with one in the edge of the South Polar Hood.

–The south polar polygon of cyclones is probably pentagonal again, but its centre is further from the pole than previously observed.

The text is in this PDF:     PJ26-report-JHR_text.pdf

Miniature copies of the figures are in this PDF:    PJ26-report-JHR_minifigs.pdf

Full-size figures are in this ZIP file:     PJ26_report_Figures.zip

Seven animations of JunoCam maps (Four pairs of maps covering the S. Temperate domain, one of the S4 domain, a triplet of south polar maps, and a blink showing the shadow of an inner satellite on the EZ) are in this ZIP file:     PJ26_report_Animations.zip

Below are (Fig.7) an excerpt from the global map, and (Anim-D) part of the S. Temperate map animation.

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