[6]  New outbreak in the SEB (report, 2007 May 27th)


On 2007 May 17,Chris Go discovered a new small bright white spot in the SEB at L2 = 180, appearing within a pre-existing dark 'minibarge'.

This is a surprise: It appears to be the start of bright rift activity again!  In this location f. the GRS, it could be a last flurry of 'routine' activity, which will soon die away – or it could be a premature start to a full SEB Revival!  We will find out over the next few days or weeks. 

It's very interesting that it appeared precisely in one of the dark reddish mini-barges.  That is exactly where a mid-SEB outbreak began during the Voyager imagery, and we suspected that the 1993 SEB Revival also began in one. This event may confirm my suspicion, that such events commonly begin within these mini-barges, although there have rarely been v-hi-res obs'ns to show it.

Unfortunately, southern hemisphere observers have not been able to take images in the last week, but some images from the northern hemisphere help to track the outbreak.  Thanks especially to the ALPO-Japan, for posting some images.  The outbreak has continued to develop, with a bright rift extending Np., and dark material extending Sf. into STrD-2 (reversing its recent fading) - as expected from the currents in this area.  Also a small
dark spot has appeared which may be retrograding past STrD-2. But the outbreak is still not conspicuous in images of moderate resolution, 10 days
after it started, so it is still possible that it will die away.

The SED was passing it around May 27. The SED is marked by a brilliant great white spot (dazzling in Rich Jakiel's image of May 27).

John Rogers,
Jupiter Section Director,
British Astronomical Association.