[BAA 00287] Jupiter: a SEB Revival outbreak

[Rick]

BAA electronic bulletin No. 00287 - http://www.britastro.org/

Jupiter: a SEB Revival outbreak

Events on Jupiter have progressed surprisingly fast since the news item in the June BAA Journal was written.  As predicted therein, the South Equatorial Belt (SEB) did start to fade: i.e. the southern belt component became progressively lighter and more diffuse from April onwards, as did the two South Tropical Disturbances attached to it.  The belt preceding the Great Red Spot faded fastest, and the GRS became a prominent isolated reddish oval.  On historical grounds, the SEB(S) was expected to continue fading until it was white, after which a violent 'Revival' would break out.

However, the Revival outbreak has started unexpectedly early. On May 17, Chris Go (Philippines) discovered a new white spot appearing within a dark spot ('mini-barge') at L2=180 (just as a mid-SEB outbreak imaged by Voyager in 1979 started precisely in the centre of a mini-barge).  It progressed slowly at first, but by early June it has developed the typical spectacular form of a SEB Revival outbreak.  Bright and dark spots continue to arise at the source longitude, with the turbulent white spots or streaks in the belt drifting to lower longitudes (towards the GRS), and dark spots on SEB(S) drifting rapidly to higher longitudes.

Interaction with the two South Tropical Disturbances will be of special interest.  The outbreak started very close to STrD-2, but STrD-2 has now faded and may be breaking up.  If STrD-1 persists, the retrograding spots will encounter it in early July and might recirculate at its p. end.  STrD-1 is at L2 = 326, just following red oval BA at L2 = 310.  The GRS is at L2 =
120.

The global upheaval has also made major changes in other belts and zones. The southern Equatorial Zone is very disturbed by the South Equatorial Disturbance, and the middle of the Equatorial Zone is exceptionally dark. The North Temperate Belt has fully revived after the great outbreak in the spring, and at some longitudes is notably reddish, while the NTropZ and NTZ
contain complex shading as a result.

Any member who would like to receive further information and image compilations should e-mail John Rogers (jhr11 at cam ac uk) and request to be put on the Jupiter Section e-mailing list. 

John Rogers

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