Annotated PJ3 images: (1) South Pole

2016-12-18 13:53 UT
Credit : NASA / SwRI / MSSS / Gerald Eichstädt / John Rogers © cc by
Submitted By : Philosophia-47
Mission Phase : PERIJOVE 3

This is the first of a series of posts pointing out features of interest in the perijove-3 images. In many cases I started from versions processed by Gerald Eichstädt, who has devised an algorithm that completely removes the artefactual colour banding. I then applied gradients and further adjustments to improve the visibility of features, though there is scope for doing better.

This image was taken directly above the south pole, which is in sunlight. It beautifully confirms and extends the discoveries made by JunoCam at PJ-1, most notably the cluster of circumpolar cyclones (CPCs). Five CPCs are visible, 4 surrounding a fifth which is distinguished by being largely dark, and the latter may well overlap the south pole (whose position is approximate). Similarly at PJ-1 there were 3 or 4 CPCs surrounding a darker fifth, with the S.Pole estimated to be on the edge of this dark central CPC.

The rest of the south polar region is, again, largely filled with turbulent cyclonic folded filamentary regions (FFRs), plus a scattering of small white ovals which are probably all anticyclonic. A loose ring of them again suggests the presence of a retrograde jet at ~72 deg.S.

Also marked are some anticyclonic white ovals (AWOs) which we have tracked from Earth. S4-AWO-1 is also known as the South Polar Little Red Spot.