Jupiter in 2011/12: Final report up to 2012 February [2015 June]

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1 Jupiter in 2011/12: Final report up to 2012 February [2015 June] John H. Rogers & Gianluigi Adamoli, using results from the JUPOS team (Hans-Joerg Mettig, Gianluigi Adamoli, Michel Jacquesson, Marco Vedovato, Grischa Hahn) TABLES, FIGURE LEGENDS, & MINI-FIGURES TABLE 1 [next 2 pages] Summary of measurements, : S. hemisphere (JUPOS data - GA's analysis) This Table lists the major individual spots (black type) and means and standard deviations for currents (red type). L2(O) = L2 at opposition on 2011 Oct.29 Dates are those for track measurement; the spots may have been followed for longer with variable or imprecise drift rate. N = no. of measurements, for single spots; no. of spots (in brackets, no. of track segments), for means. Region/Spot Dates L2(O) DL2 Lat N Notes (deg/mth) S4 domain AWO - WS1 Jul 11 - Dec ,-34,-3,-38,-6-58,6 to -60,1 Oscillating (Mean ~ -19) (Mean = -59,6) (2.5 cycles, P ~ 2.3 months) AWO - WS3 Jul 4 - Feb ,-35,+5,-29-58,7 to -60,3 Sudden changes of speed: S3 domain AWO - WS1 Jul 1 - Oct ,5 Slightly variable speed throughout, Oct 5 - Jan ,9 with abrupt change in early Oct. S3TZ dark spots Mean: 13,0-49,0 11 SD: 4,3 0,32 S3 jet: white spots Mean: -93,6-43,8 8 (12) SD: 4,1 0,16 S2: AWOs Mean: -28,7 [-40,5] 9 SD: 3,4 [assumed] S2 jet: dark spots All: Mean: -96,8-35,5 15 (21) All spots between lats -35,0/-36,5 SD: 11,6 0,4 (except one slow spot); Peak: Mean: -110,5-36,0 4 Only spots at lat.36,0 (+/-0,2). SD: 4,1 0,1

2 S1 domain (STC): oval BA May 14 - Jul 20-13,4-33,0 34 Jul 24 - Aug 25-18,9-33,2 36 Aug 27 - Jan ,2-32,9 159 Feb 23 - Apr 6-10,1-32,9 10 d. spot f. BA Sep 21 - Dec ,0-30,9 27 Previously a streak Dec 10 - Feb 4-8,5-31,6 12 tiny AWO WS1 Jul 22 - Aug 31-19,9-33,7 27 Sep 2 - Oct 9-13,4-33,6 47 Oct 13 - Dec ,6-33,6 59 tiny AWO WS2 Jul 24 - Aug 25-16,3-33,5 17 Sep 6 - Oct 2-7,2-33,3 26 Oct 15 - Nov ,5-33,6 20 DS1 (v.d.s.) Jun 26 - Sep 11-14,4-30,7 80 Sep 12 - Oct 26-9,4-31,3 38 Oct 31 - Dec ,6-31,0 22 Turning pink DS4 (v.d.s.) Aug 24 - Mar ,6-30,9 198 P. dark STB July - March P. end: Generally DL2 = -17 but F. dark STB June - Jan with two shifts of ~7 deg. p. STBn jet: dark spots (All) Mean: -93,2-28,0 24 SD: 5,25 0,46 (Peak) Mean: -98,6-27,5 9 SD: 2,78 0,22 SEBs jet [Full table is in Appendix 1 of the report] Waves (d.&w.) (Set 6) Mean: 38,4-20,0 10 SD: 0,74 0,45 White spots (Set 7) Mean: 131,2-20,7 12 SD: 5,19 0,25 S.Trop.C. GRS May 22 - Apr ,8 1,07-22,0 277 W. area in SEB Aug 7 - Sep 6-11,1-13,8 33 Sep 9 - Feb 1 103,5-4,2-14,0 123 Feb 5 - Mar 29 0,3-14,6 17 Mini-barges Mean: 7,3-16,9 5 (11) SD: 4,5 0,2 SEB(N) w. spots Mean: -112,4-11,4 25 SD: 10,1 0,5 SEBn jet: chevrons Mean: -296 (-7) SD: 6 (assumed)

3 TABLE 2 [next 2 pages] Summary of measurements, : N. hemisphere (JUPOS data - GA's analysis) This Table lists the major individual spots (black type) and means and standard deviations for currents (red type). L2(O) = L2 at opposition on 2011 Oct.29 Dates are those for track measurement; the spots may have been followed for longer with variable or imprecise drift rate. N = no. of measurements, for single spots; no. of spots (in brackets, no. of track segments), for means. Region / spot Dates L2(0) DL2 Lat. N Notes (deg/mth) NEBs jet: NEBs dark projections (means) --slow Mean: ,7 5 (DL1 = +26) --super-fast Mean: ,5 ~100 (DL1 = -76 to -83) N. Tropical current Major barges: (omitting short track segments; see JUPOS chart for full tracks) B1 Jul 1 - Oct ,3 15,4 111 Oct 31 - Mar ,7 14,9 102 B2 Jul 14 - Aug ,2 15,5 33 Sep 2 - Oct ,8 14,8 72 Nov 22 - Mar ,5 15,1 73 B3 May 29 - Sep ,1 15,0 23 Sep 28 - Mar ,5 15,6 75 B4 Jul 10 - Dec ,3 15,5 125 B5 Jun 11 - Aug ,7 15,4 20 Aug 13 - Apr ,6 15,6 107 B6 Jul 1 - Mar ,3 15,0 190 Oscillating Mean: -6,6 15,3 6 (11) SD: 3,1 0,30 NEBn jet: dark spots Mean: 33,0 17,1 5 DL2 range +29 to +43 SD: 6,1 0,46 N. Trop.C. (cont.) Major white spots/bays (AWOs): W8 Aug 18 - Sep ,6-4,3 18,3 25 Last track of former ADS-2 AWO-1 Jun 1 - Sep 4 215,1-1,8 17,5 51 Sep 26 - Dec ,9-2,8 18,4 39 AWO-2 Jun 11 - Oct ,5 17,9 81 Oscillating. Former ADS-3. AWO-3 Jun 14 - Sep ,0-2,5 17,8 44 Former WS-Y.Later accelerated. WSZ Jun 14 - Jan 8 350,2-11,1 20,2 185 Jan 11 - Mar ,0-8,8 20,4 18 Mean: -5,1 18,6 5 (7) SD: 3,5 1,2 N1 (N. Temp.) domain NTC-B: Small dark spots Sep-Dec. Mean: -55,8 28,0 N = 10 in NTB SD: 6,3 0,51

4 NTC-A: Streaks/spots on NTB(N): V.d. brown streak June-Oct ,0 29,7 V.d. brown streak June-Oct ,0 29,7 Orange spot July-Sep ,0 30,2 Small w.s. Sep.-Nov ,9 31,9 Small dark spots July-Dec. Mean: 21,1 32,3 N=7 (inc. one which later recirculated) in NTZ SD: 7,2 0,51 DL2 Lat N2 jet: dark spots Mean -88,7 35,0 DL2 range -72 to -105 DL2 8,51 0,47 N = 44 N2 domain (NNTC) NNTB d. streaks: str1-p.e. Oct - Mar 38-11,2 37,6 52 str1-f.e. Sep - Feb 72-12,0 37,6 50 str3-f.e. Jul 28 - Dec ,7 37,9 116 str4-p.e. Nov 3 - Jan ,1 38,0 19 str4-f.e. Oct 17 - Jan ,2 37,9 31 str5-p.e. Aug 7 - Sep ,9 37,8 42 str5-p.e. Sep - Nov 160 3,7 str6-p.e. Jun 1 - Aug ,0 37,9 27 str7-f.e. Jun 28 - Aug ,5 38,0 23 DS1 Sep 17 - Jan ,4 38,1 133 Mean (exc.no.1) 0,0 37,9 N=8 SD: 4,1 0,1 NNTZ ovals: NN-LRS-1 Jul - Feb 68-10,5 41,0 many Var.; Inc. methane images WS-7 Jun - Dec to +12 var 142 Var. WS-4 Jun - Jan to ,9 226 to -12 WS-6 Oct 15 - Feb ,1 41,2 58 Earlier, var. N3 domain (N3TC) Mean -15,4 45,4 13 Mean limited to 'core group' of dark spots with DL2 Dark spots SD 2,3 0,27 from -10 to -20, lat.45 to 46 N (about half the spots in N3 domain) (N3TC). W2 Nov 25 - Jan 4 (125) -30,6 46,3 25 AWO translocated from N4 domain (W3) D.ss. in NNTZ (fast) Mean -32,8 41,8 7 Flank of N4 jet. SD 9,2 0,2 N4 domain (N4TC) Dark spots Mean 4,6 50,8 18 Means of all spots at N (N4TC) SD 5,2 1,1 White spots Mean 5,1 52,0 8 (12) SD 5,4 1,2 including AWOs: (See fuller table in report text.) WS-a (W7) Jun 28 - Nov ,1 51,8 174 WS-b (W3) Sep 23 - Nov ,0 51,4 61 Then translocated to N3 domain (W2) N5 domain Mean 13,5 60,4 11 Mean of all spots, N. SD 7,3 0,8 (4 white, 7 dark) (See text for individual spots.) N6 domain White spot Sep 24 - Oct 23 67,6-91,4 67,3 28 Oct 26 - Dec 20 76,4-46,6 66,5 32

5 Figure legends with thumbnail figures South is up in all figures. Fig.1: Map, 2011 Nov (images by Damian Peach, map by Marco Vedovato). (See Figs.9 & 35 for same data in polar projections.)

6 Fig.2. Multispectral images in 2011 August, all by Tomio Akutsu unless otherwise stated. CH4, methane absorption band at 889 nm; IR, near-infrared continuum; UV, near-ultraviolet; with false-colour composites.

Of the NNTZ ovals, LRS-1 is strongly methane-bright, WS-6 and -7 weakly methane-bright, and WS-4 very weakly so (not visible at all on some methane images).

7 Fig.3. Methane-band images, all by Tomio Akutsu unless otherwise stated. Anticyclonic ovals are normally methane-bright, including the S2 AWOs (visible but not marked), oval BA, the GRS, and 3 of the 4 ovals in the N2 domain (NNTZ). Of the NNTZ ovals, LRS-1 is strongly methane-bright, WS-6 and -7 weakly methane-bright, and WS-4 very weakly so (not visible at all on some methane images). However, AWOs in the NTropZ are not methane-bright; even White Spot Z is only weakly detectable (marked Z). Fig.4. True-colour and methane-band images in 2011 Nov-Dec., showing the GRS and the SEB f. it, where new plumes in the rifted sector are often methane-bright for a few days. The best images show that small high-latitude AWOs are also methane-bright, e.g. S2-A8, S3-ws1, and S4-ws3.

methane band (Astronomik, 12 nm width), and ultraviolet (Schüler).

8 Fig.5. Maps made by Silvia Kowollik from her own images taken with a 0.8-metre Cassegrain by courtesy of the Observatory Zollern-Alb, Germany, in visible colour, methane band (Astronomik, 12 nm width), and ultraviolet (Schüler). Methane-bright anticyclonic ovals are marked. Fig.9. South polar projection map made from images by Damian Peach on 2011 Nov (same data as Fig.1).

9 Fig.6. Zonal drift profile (ZDP; speed versus latitude) for the southern hemisphere, from our JUPOS data, compared with a typical spacecraft-derived ZWP, from Cassini [ref.8]. As in all our ZDPs in this report, the large number of points represent many small spots as well as multiple track segments for larger spots, divided up to obtain the most precise values possible. Fig. 7. Same as Fig.6, for the northern hemisphere.

10 Fig.8. Global ZDPs from our JUPOS data for 2005 and 2006 [ref. 10] and 2007 [ref. 11]. Fig.9 [shown above with Fig.5]. South polar projection map made from images by Damian Peach on 2011 Nov (same data as Fig.1).

Fig.10. The GRS and latitudes south in 2011 Oct., with long-lived AWOs in the S2, S3 and S4 domains undergoing interactions as decribed in the text. Fig.11. ZDP for the AWOs in the S4 domain.

11 Fig.10. The GRS and latitudes south in 2011 Oct., with long-lived AWOs in the S2, S3 and S4 domains undergoing interactions as decribed in the text. Fig.11. ZDP for the AWOs in the S4 domain. As in all our ZDPs in this report, the numerous points represent many small spots as well as multiple track segments for larger spots, divided up to obtain the most precise values possible.

12 Fig.12. Images showing development of local circulation(s) in the STZ ~60 p. oval BA in 2011 Aug-Sep., including appearance of the small dark spot DS4 in the STB, which in later years became STB structured sector E (the STB Ghost ).

13 Fig.13. V-hi-res images of oval BA, and the dark STB patch and small AWO f. it. Fig.14. Long-term JUPOS chart of oval BA, , showing its abrupt changes of speed.

STB latitudes reddening and whitening. (Also see Fig.1.

Images in 2011 May, early in the apparition, showing

the GRS, and disturbance in the northern SEB f.

14 Fig.15. Excerpts from maps, showing the very dark spot DS1 in STB latitudes reddening and whitening. (Also see Fig.1.) Fig.16. Images in 2011 May, early in the apparition, showing the S.Trop.Band developing p. the GRS, and disturbance in the northern SEB f. the GRS persisting from the SEB Revival. In the NTropZ, white spot Z (at L2 ~ 45) is very bright. Fig.17. Map on 2011 June 8-12, showing the S.Trop.Band developing p. the GRS...

Fig.17. Map on 2011 June 8-12, showing the S.Trop.Band developing p. the GRS, and intense disturbance in the northern SEB f. the GRS persisting from the SEB Revival.

15 Fig.17. Map on 2011 June 8-12, showing the S.Trop.Band developing p. the GRS, and intense disturbance in the northern SEB f. the GRS persisting from the SEB Revival. (The image from June 8 has been inserted without map-projection, and thus does not fit the map scale accurately.) Fig.18. ZDP chart for the S. Tropical domain. Spots are grouped as defined in Appendix 1. Fig.19. Images showing the SEB in 3 different epochs, showing how a slowly retrograding spot-chain or wave-train (purple marks below) co-exists with rapidly retrograding features in the same latitude (black arrows above). (A) 2010 July, during the SEB Fade; gaps in the wave-train had full jet speed. (B) 2010 Dec., during the SEB Revival; dark spots in the southern branch of the Revival had full jet speed. (C) 2011 Aug., after the SEB Revival; tiny bright spots had full jet speed.

(There were also v-hi-res images by Peach on Sep.23/24, Sep.27/28, and Oct.

16 Fig.20. The GRS and the onset of new SEB rifting, 2011 Sep., including some paired ultraviolet and methane-band images. (There were also v-hi-res images by Peach on Sep.23/24, Sep.27/28, and Oct.3, which have been posted already in our sets of hi-res maps and satellite images: reports nos. 2 & 3.) Fig.21. The GRS in 2011 Nov.

Fig.22. Maps of the EZ and NEB in 2011, aligned in L1 or (for closely spaced maps in Nov.) in L1 minus 2.0 deg/day to identify individual super-fast projections.

17 Fig.22. Maps of the EZ and NEB in 2011, aligned in L1 or (for closely spaced maps in Nov.) in L1 minus 2.0 deg/day to identify individual super-fast projections. The few remaining normalspeed projections are indicated by green arrows, from the JUPOS charts; there is nothing to visibly distinguish them from the super-fast ones.

Fig.23. Hi-res images tracking some super-fast NEBs projections in 2011. Fig.24. Chart of speed ranges vs time for the super-fast NEBs projections in 2011/12. For Aug-Sep.

18 Fig.23. Hi-res images tracking some super-fast NEBs projections in Fig.24. Chart of speed ranges vs time for the super-fast NEBs projections in 2011/12. For Aug-Sep., the projections are divided into those p. the few remaining slow projections (a) and those f. them (b), and a few outliers (individual values very different from most of the group) are shown separately.

19 Fig.25. ZDP for N. Tropical domain. Fig.26. Sections of maps showing the shrinkage of the NEB. (Maps labelled MV were constructed by Marco Vedovato.)

Fig. 27. Maps showing the evolution of the NEB and NTB: latitudes 0-50ºN, from the same set of maps as in previous figures. AWOs of the NTropZ and NNTZ are labelled, as well as key features of the N.

20 Fig. 27. Maps showing the evolution of the NEB and NTB: latitudes 0-50ºN, from the same set of maps as in previous figures. AWOs of the NTropZ and NNTZ are labelled, as well as key features of the N.Temperate domain that led to the reappearance of the NTD. Fig. 28. ZDP for N1 (N. Temperate) domain. This chart shows points for minor spots and short track segments as well as the major features listed in the Table. As usual, spots on both sides of the retrograde jet move with the slow current (NTC-A, DL2 ~ +20 deg/mth), and the ZDP is blunter than the ZWP on the retrograding side, so the full speed of the retrograde jet is not detected. Conversely the ZDP agrees well with the ZWP on the prograding side, particularly the ZWP from Voyager which in the NTZ is ~0.4º S of the Cassini ZWP shown. Our ZDP is the same as in 2009 [ref. our 2009 report no.8]. The chart also marks the track of two spots which recirculated from the NTBn to prograde in the NTZ: one in 2011 Sep., and one from the previous apparition in 2010 Nov. which did start on the retrograde jet.

Fig.29. Sets of images covering a sector of the N1 and N2 domains, showing the renewal of NTB rifting in 2011 Sep., and developments which led to the reappearance of a NTD in Oct.

21 Fig.29. Sets of images covering a sector of the N1 and N2 domains, showing the renewal of NTB rifting in 2011 Sep., and developments which led to the reappearance of a NTD in Oct.; also showing activity on the N2 (NNTBs) jetstream. (A) Images from 2011 August. This set shows: --WSZ in NTropZ, and NN-LRS-1 in NNTZ (red arrows). --The NTB rifted region or FFR (marked above in green; small and inconspicuous at this time, but still active), with dark brown streaks f. it, and NTZ dark spot D8 (black arrow) between them. --A small FFR on the Sp. edge of NN-LRS-1. --NNTBs jet spots: tiny dark spots numbered 1-7 in order of appearance. Sometimes a new spot is connected to a cusp of dark NTBn by a tenuous wisp (small oblique black arrow). (B) Images from 2011 Sep.1 to Oct.15. This set shows: --The rifted sector of NTB, reappearing in Sep., p. the orange streaks. --The pair of NTBn dark streaks, now orange and fading. --Two dark blue-grey spots in NTZ, which successively reverse their drift from retrograding (NTC-A) to prograding. V-hi-res images show both become anticyclonic rings. They are: --D8, at p. end of the orange streaks; it becomes slightly prograding, but becomes more difficult to track as it passes alongside the increasingly turbulent rifted sector. --D9: forms in late Sep. from a changeable narrow streak f. D8. It forms as two NNTBs jet spots interact with it. (They go on to disappear when interacting with D8. The third NNTBs jet spot disappears when it contacts D9.) --(D10:) a third such spot can be seen forming as a pair of tiny dark blue spots interact on Oct NNTBs jet spots: A pair passes through this region smoothly in Sep. Later, a triplet progrades into the region and all three disappear as they interact with one or both NTZ dark spots. --Very dark streaks of NNTB; AWO (WS-7) in NNTZ; a FFR immediately f. it (beautifully resolved in Peach s v- hi-res images). --Further f., another very dark streak of NNTB is brownish-grey, and becomes redder in Oct., fading. --NN-LRS-1, invisible in most images as it has low contrast, but its oval form is evident in v-hi-res images. (It is also very methane-bright; see Fig.3).

22 Fig.30. Maps showing the NTB and NNTB: latitudes 20-50ºN, from the same set of maps as in previous figures, with features of the N1 and N2 domains marked.

23 Fig.31. ZDP for the N2 domain. See text for details. Fig.32. An AWO moving from the N4 to N3 domain, as described in the text..

Fig.33. Charts of the AWO moving from the N4 to N3 domain. The oval (N4-AWO-b) was originally numbered N4-W3, and became N3-W2. (A) JUPOS charts of L2 and latitude vs time.

24 Fig.33. Charts of the AWO moving from the N4 to N3 domain. The oval (N4-AWO-b) was originally numbered N4-W3, and became N3-W2. (A) JUPOS charts of L2 and latitude vs time. (Grey band marks N4 jet, range of latitude measurements from spacecraft.) (B) Summary of data, as plotted in (C). (C) ZDP chart, showing that the spot adhered closely to the ZWP throughout this transition, splitting just as it crossed the prograde N4 jet, presumably due to the anticyclonic shear on its S flank. Fig.34. Encounter between two white ovals in the N5 domain, 2011 August, as described in the text.

Hi-res images showing the galilean moons from 2011 Dec. to 2012 Feb.

25 Fig.35. Five north polar projection maps in 2011 Nov-Dec. Some of the northerly AWOs are marked. Some of the irregular light patches likely to be FFRs are marked, where they can be identified from one map to another. They are at ~47-53ºN (green), 57-62ºN (mauve), 70-75ºN (cyan). Fig.36. Hi-res images showing the galilean moons from 2011 Dec. to 2012 Feb. Surface features are detected on Ganymede (as shown in the two WinJUPOS simulated images), and on Io (the dark polar caps and a dusky band near the central meridian). From left to right, top row: Ganymede just before transit (similar aspect to the bottom row); Ganymede just before occultation (with simulation); Io in transit near the GRS (x3). Bottom row: Ganymede in transit. The images detect the bright ray system of Osiris crater; Galileo Regio; an unnamed dark area on the f. side (further darkened by the phase effect); and the white north polar cap, which becomes invisible against the clouds below.

(Final: 2015 July 16) Zonal wind profiles from ground-based and Hubble images, 2014 February and April

(Final: 2015 July 16) Zonal wind profiles from ground-based and Hubble images, 2014 February and April Grischa Hahn (JUPOS team) & John Rogers (BAA) Summary We have generated zonal wind profiles (ZWPs)