[BAA-ebulletin 00702] Jupiter: Progress of the great northern upheaval

[BAA electronic bulletins service]

Jupiter: Progress of the great northern upheaval

In the 3 months since the last e-bulletin about Jupiter, the great disturbances on the North Equatorial Belt and the North Temperate Belt led to the complete revival of both dark belts by the end of July, and the revived belts and the zone between them all adopted a dull reddish colour - the most widespread coloration event on the planet for many years.  There was also a reddish Equatorial Band stretching half way around the equator.  The scale of the disturbances was progressively decreasing, and from August onwards the planet has appeared to be settling down into a more normal state, with some clearing of the zone between the revived belts. This does not mean that the planet is quiet: far from it.  The NEB Revival has created an impressive array of dark blue-grey formations on the NEB south edge.  Within the belt, tiny bright spots have been appearing and expanding to restore typical bright 'rifts'.  And in the north part of the NEB, we can see the initial stages in formation of a new array of small dark brown spots ('barges') and white ovals.  All this has happened remarkably quickly.

There are also plenty of features to observe in the southern hemisphere, including red oval BA which has just passed the Great Red Spot (at L2 = 183).

Meanwhile, a bright fireball was observed in the atmosphere of Jupiter, on 2012 Sep.10 at 11:35 UT. It was first reported by a visual observer, Dan Petersen in Wisconsin, and then identified in a video by George Hall in Texas. It was a bright flash lasting only about 2 seconds. This was was similar to two fireballs observed in 2010, and like them, it left no detectable trace on the planet's surface. 

We have uploaded several new reports about all these events, with many image compilations, on the BAA Jupiter Section web site at:

http://www.britastro.org/jupiter/2012_13reports.htm

The planet is now very well placed for observation and new observers will be welcome.  Please check our web site for the format of observations, and e-mail them to the undersigned. 

John Rogers, 2012 Oct.9

_______________________________

John H. Rogers, Ph.D. 
Jupiter Section Director,
British Astronomical Association

<jhr11 at cam.ac.uk>
http://www.britastro.org/jupiter/
_________________________________