Whole activity of mid-SEB outbreak started during solar conjunction has revealed, at last. Its source is located at II:190.4 deg. (Oct. 30, Akutsu), and light band is formed between GRS about 100 deg. in longitude with many white spots inside. Among white spots, the closest one to the source is the brightest, while preceding ones are generally dim with diffuse outline. Because source position almost remain unchanged since September, it is seemed that new spots are still forming from it. Light band is positioned about center of SEB near the source, but it gradually shifts northward with decreasing longitude, and occupies northern half of SEB following GRS. This aspect resembles that in February, 2003. The date the activity begun could not be determined, because no observation was reported for this region prior to Sep. 17, when Horikawa discovered the activity first, even in BAA interrim report (Rogers).

SEB is triple following f. end of mid-SEB outbreak, with extremely dark component in mid-SEB. SEBs edge is active with a lot of rings and projections, many of which are conjectured rapidly retrograding on SEBs jetstream.

GRS is at II:88.0 deg. (Oct. 15, Einaga), which is seen as somewhat faint oval with diffuse outline, but prominent with strongly orangish tint. Dark arch surrounding south edge is hardly seen, and its interior is almost uniform, though southern half is somewhat darker. In late stage of the last apparition, dark arch and irregular dark patches were seen, due to collision of SEBs ring spot with GRS taken place in April 2003. But GRS has recovered original aspect by now.

BA is seen as dim indistinct oval at II:211.8 deg. (Oct. 25, Ng). Dark spot immediately following BA observed outstandingly in last apparition has changed into a belt fragment about 30 deg. in longitude. It is notable that another dark segment of STB is approaching BA. In last apparition (February 2003), the space batween BA and p. end of the segment was 120 deg. apart in longitude, but this month, the p. end has reached at about II:270 deg., having decreased the space by nearly half over 8 months, since rotation period of the segment was 9 seconds (-0.2 deg./day) shorter than BA. Within the sector bounded by the segment and preceding one immediately following BA, irregular dusky patches are developing, therefore it seems that both segments would merge in the near future. In faded STB, there is a prominent dark spot at II:147.5 deg. (Oct. 20, Ng), and it is probably the same object as that seen in last apparition as similar but less conspicuous spot preceding BA.

NEB is narrower, having width of around two thirds of SEB, and its northern edge is generally flat with few barges. In NTrZ, there is a white oval at around II:200 deg., forming shallow bay on NEBn, which is the long-lived oval called 'Z' surviving from 1997. Ng's images showed fully developed rift within NEB at II:100-150 deg. (Oct. 20 and 22). On NEBs edge, a lot of outstandingly bluish dark masses are seen accompanying with dark festoons. It seems that dark prominent festoons are more frequently observed than in last apparition. Northern half of EZ is slightly yellowish in contrast to whitish EZs, and EB is fragmentary and indistinct.

Faded NTB is barely seen as faint trace of belt, forming boundary between light NTrZ and a little duskier NTZ. Also, in faded NNTB latitude, several belt segments or fragments are seen, but it cannot be determined whether they are part of NNTB or more northern belt segments.

(2) Saturn

Saturn already passed western quadrature on Oct. 6, and stationary on Oct. 26. This month, we have received observations listed below.

No observations are made in this month for STrZ white spot which appeared last month. Though extremely high resolution imeges are obtained by Grafton on Oct. 20 (III:180 deg.) and Ng on Oct. 21 (III:193 deg.), no oval can be seen around -40 deg. in latitude, where STrZ is uniformly light. It seems that the spot might have already disappeared.

In Grafton's image taken on Oct. 19, tiny dark spots are seen in STrZ at around III:100 deg. But it would be required considerable good condition and high resolution to track such delicate features.

In the other region, it is notable that fading of SEB south component is under way. Though fading of the component started early stage of last apparition, in contrast to dark reddish northern SEB, southern part is seen as gray faint belt this month, having low contrast against light STrZ. So, only northern half of SEB can be seen in images taken in poor condition. On Jupiter, the process in which faded SEB recovers its original darkness is very violent phenomenon known as SEB Revival (SEB Disturbance). It is much interesting what activity is observed in case of Saturn.

(November 7, K. Horikawa)

[Fig.1] GRS with mid-SEB outbreak

2003/10/15 20:47UT

I=232.4 II=93.6

25cm Refl. H. Einaga

[Fig.2] Mid-SEB outbreak and BA

2003/10/25 22:06UT

I=58.5 II=203.0

30cm Refl. E. Ng

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