A little change was seen in activity of mid-SEB outbreak. Though source position (f. end) of the outbreak had been almost constant around II:190-195 deg. in September and October, it was gradually prograding and reached at II:169 deg. (Nov. 25, Fukui). In previous outbreak took place in 2002 Dec., the creation of white spots at its source region had come to an end in March 2003 after 3 months activity, and turbulent sector of white clouds had contracted repidly and disappeared. Assuming that this outbreak began in August, it had passed just 3 months, and it can be reagrded that the activity was declining. But its prograding rate was less than -1 deg./day which was much slower than previous outbreak, and it is possible that source position was almost stationary around II:170 deg. in the second half of November. Also, this month, SEBn faded to form light band between f. end of outbreak and II:250 deg. where reddish dark spot had been seen in mid-SEB since early stae of the apparition. Therefore, it was hard to locate source position of the outbreak. In other sectors, SEB was dark and prominent between central component and northern edge, but high resolution images revealed that numerous white spots like tiny bubbles were seen in SEBn following reddish spot described above.

RS was at II:91.4 deg. (Nov. 25, Miyazaki) with prominent orangish tint. No arch was observed, but f. end was connected with SEB by gray streak in early and late November. BA was at II:207.0 deg. (Nov. 6, Fukui) surrounded by dusky collar, but oval itself had no brightness with low-contrast agaist surroundings. Dark broad STB was seen only between II:270 and 320 deg., following which somewhat southely thin component, probably STBs, was extending up to II:20 deg. Other prominent features in this latitude were solitary tiny dark spot following RS (II:138.9 deg., Nov. 6, Nakanishi), dusky spot immediately following BA, and dark spot (II:248.8 deg., Nov. 21, Sherrod) just preceding STB dark segment described above. South of STB, three belt components could be seen in the range -35 to -47 deg., which made it difficult to give correct names. It was probably regarded as follows: the central one lying between -38 and -41 deg. was true SSTB (II:50-130 deg., 280-0 deg., etc.), northern one between -35 and 37 deg. was STZB (II:180-280 deg.), and the other one between -42 and -47 deg. was (S)SSTB (II:0-90 deg., etc.). SSTB small white spots were distributed in the limited range of longitude, as seen previous apparition, when five spots could have been seen in 90 deg. range. This month, four spots located between II:140 and 200 deg., and the rest one was at II:110 deg. at a distance.

Northern half of EZ was lightly shaded and yellowish with many festoons, some of which were associated with blue-gray dark mass on NEBs edge. But the sector ranging I:100 to 200 deg. was relatively quiet with indistinct festoons. NEB appeared to be the most active in recent years due to rift activity. It was seen double in many longitudes with irregular white spots and streaks, which seemed to be prograding rapidly relative to System II. NEBn edge was generally smooth with few projecting barges, except between I:100 and 200 deg. where it was irregular with humps and bays.

North of NTB was quiet unchanged. At +36 deg. in latitude corresponding to NNTBs edge, there were several tiny dark spots around II:200 deg. Our section reported in previous apparition that nine dark spots had been moving with NNTBs jetstream speed (Average: 9h53m55.2s, s.d.: 4.8s). Therefore, these spots were also similar feature, which had not be confirmed yet.

(2) Saturn

The opposition in this apparition will come around on New Year's Day of 2004. Saturn is in good period for observation. This month, we have received observations listed below. As in Jupiter part, Akutsu (Hiroaki), Ota, Kanno, Neichi, and Fukui from ALPO-Japan joined as new contributor.

On Saturn, delicate features that could not be able to see before are frequently observed due to improvement of equipments for amateurs in recent years. Such features were observed again this month. It is likely that Saturn surface may be more active than it had ever been considered.

Grafton's image taken on Nov. 4 showed a white spot in STZ around III:45 deg. Surprisingly, 4 white spots were seen together on his single image taken on Nov. 30, on which each one spot was seen in STZ and STrZ, and two were in SEB. All of these seemed to be substantial feature, not noise in image processing, because these features moved a little in another image taken 8 min. later. Ikemura created an animation from several images taken on Nov. 7, which showed that faint small dark spot in mid-SEB and adjacent shadings were moving with planet's rotation. These were close in longitude to Grafton's features on Nov. 30, but it was uncertain whether they were identical.

T. Akutsu continues to taking image by methan absorption band (893nm), which is rare for saturn. In this wavelength, EZ was light while SEB and polar region was dark, which characteristics were generally coinside with those in visual wavelength. It is interesting that, SEB appeared as broad belt in methane band, while it was narrow visually fading away its southern half.

(December 10, K. Horikawa)

[Fig.1] Source position of mid-SEB outbreak

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