On a CCD image taken by Don Parker on 2004 July 14, the NTrZ was one of the brightest zones on the planet, even out shining the EZ which had a dusky, yellow-ochre appearance over most of its width.
The North Equatorial Belt (NEB) is home to some of the most obvious and reliable features on the planet. During most apparitions, condensations, barges, festoons, ovals, and projections can be seen in the belt or on its edges. While many of the belts and zones on Jupiter are low in intensity, the NEB is often one of the three darkest features of the planet. During the apparitions of 2000-2001 and 2001-2002 the belt generally appeared solid and wide with a reddish brown coloration reported by most observers (Fig. 3.9).
Dark condensations of oval shape, large and small, can often be seen on the northern edge of the belt. The larger condensations are referred to as barges and seem to be most conspicuous when the NEBn has receded slightly, as though leaving these condensations in its place. The condensations are most often described as reddish-brown in color, a darker version of the NEB. Barges were very prominent during the 1997 and 1998 apparitions, with several being seen at different longitudes around the planet. During the 1999 apparition, the northern edge of the NEB receded at several locations around the planet, giving the NEB a very narrow appearance at these locations. This further gave the NEBn the appearance of being undulating and wavy, or of having bright bays protruding into the NEBn from the NTrZ. Dark condensations were noted at several places around the planet on the NEBn (Fig. 3.10).
During the 2000-2001 and 2001-2002 apparitions, the barges were much less conspicuous, with smaller condensations in their place. Even the smaller condensations were not so prominent during 2000-2001. However, during 2001-2002, something unusual occurred. During that apparition several barges, similar to those often seen on the NEBn, were discovered in the middle of the NEB at several positions around the planet (Fig. 3.11)! Several of these barges were prominent enough to be seen visually throughout the apparition. During one recent apparition, two of these mid-NEB condensations were reliably observed by CCD imaging. Over time, they drifted together and merged. I had the privilege of observing several of these mid-NEB barges on a night of good seeing with the 36-inch telescope at McDonald Observatory in Texas during the fall of 2001. The rich, reddish-brown i ^ i l-<0
Fig. 3.9. A CCD image of Jupiter, taken on October 29, 2000 revealing a wealth of detail. Surviving south temperate oval BA is seen on the STBs followed by darker material. The SEB is split by a bright SEZ. The EZ is undergoing a coloration event, with only the south most portion remaining bright. The NEB is broad, and the NTB is also very intense, both with a strong reddish-brown color. Notice the long, bright rift running through the NEB. A small, rare bright oval can be seen in the NPR. South is up. (Credit: Donald C. Parker).
CM1-83.7 CM2-277.9 CM3=239.6
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