| Observer | Location | Telescope | Images/Drawings | |
|---|---|---|---|---|
| Akutsu, Tomio | (Tochigi, Japan) | 32cm Refl. | 3 | images |
| Einaga, Hideo | (Hyogo, Japan) | 25cm Refl. | 119 | images |
| Fukui, Hideto | (Kyoto, Japan) | 25cm Refl. | 14 | images |
| Horikawa, Kuniaki | (Yokohama, Japan) | 16cm Refl. | 6 | drawings, 3 images |
| Nakanishi, Hidekazu | (Aichi, Japan) | 30cm Refl. | 4 | images |
| Narita, Hiroshi | (Kawasaki, Japan) | 20cm Refr. | 5 | drawings |
| Mishina, Toshiroh | (Yokohama, Japan) | 20cm Refl. | 2 | images |
| Miyazaki, Isao | (Okinawa, Japan) | 40cm Refl. | 16 | images |
| Takimoto, Ikuo | (Kagawa, Japan) | 31cm Refl. | 93 | images |
| Yoneyama, Seiichi | (Yokohama, Japan) | 20cm Refl. | 3 | images |
| Yunoki, Kenkichi | (Osaka, Japan) | 20cm Refl. | 6 | images |
In broadened NEB, barges and small white spots were forming in northern part of the belt. This month, four small white spots (II:80, 130, 190, 230 deg. approximately) and two barges (II:175, 215 deg. approximately) could be observed, and more will be formed. It is known that reddening of the belt follows upon a broadening event, and the belt became reddish this month, as expected. Interior of NEB, light portions involved by rift activity were seen in some places, among which those at about II:90, 260, 340 deg. (f. end longitude in late December each) were conspicuous.
RS was at II:99.5 deg. (Apr. 17, Miyazaki). Dark arch surrounding south edge and dark streak preceding it, which could be seen last month, almost disappeared remaining faint traces of them. RS itself was well-defined with dark core at its center. Following RS, SEB disturbed region by white clouds extended up to about II:150 deg., being weak activity. BA was prominent as large oval surrounded by darl collar at II:18.8 deg. (Apr. 28, Einaga). Dark broad STB segment lay between BA and RS, and two tiny white spot were observed at STZ and STBs edge just following BA. While STBs edge spot was stationary at about 30 deg. following BA, STZ spot was prograding with South South Temperate Current (about -1 deg./day), and had gotten close to BA late December. SSTB included six small white spots as shown in last apparition, and five of those began to overtake RS.
NTB was invisible at all longitudes. NNTB was seen as irregular belt at south edge of dusky NPR. Several small dark spots were observed on NNTBs edge, but it was uncertain whether those were NNTBs jetstream spots as observed last apparition.
(2) Saturn
Saturn was retrograding in Gemini. It is in good period for observation, but there were few good images due to poor condition of winter, like Jupiter. This month, we have received observations listed below. In addition, a GIF animation, in which SEB activity of white clouds in November was shown, was sent by Hirabayashi.
| Observer | Location | Telescope | Images/Drawings | |
|---|---|---|---|---|
| Einaga, Hideo | (Hyogo, Japan) | 25cm Refl. | 37 | images |
| Fukui, Hideto | (Kyoto, Japan) | 25cm Refl. | 2 | images |
| Hatanaka, Akitoshi | (Mie, Japan) | 40cm Refl. | 8 | images |
| Ikemura, Toshihiko | (Nagoya, Japan) | 31cm Refl. | 16 | images |
| Mishina, Toshiroh | (Yokohama, Japan) | 20cm Refl. | 1 | image |
| Nakai, Kenji | (Hiroshima, Japan) | 25cm SCT | 4 | images |
| Pellier, Christophe | (France) | 21cm MCT | 8 | images |
| Takimoto, Ikuo | (Kagawa, Japan) | 31cm Refl. | 90 | images |
| Yoneyama, Seiichi | (Yokohama, Japan) | 20cm Refl. | 3 | images |
| Yunoki, Kenkichi | (Osaka, Japan) | 20cm Refl. | 2 | drawings, 179 images |
SEBZ white spots and dark materials observed in November could not be traced this month. In a sector between III:160 and 220 deg., where white spots and irregularities of the belt were observed, no recognizable feature was seen due to poor condition.
There was no report to find prominent spots this month. Yunoki's image taken on Dec. 1 showed a dark column, which might be flanked by white spots, in STrZ around III:350 deg. But it could not be seen at all in his image taken on Dec. 9 showing almost the same longitude. Though there were some reports that spot-like light feature was observed, none of them were confirmed.
(January 10, K. Horikawa)
[Fig.1] |
 |
| 2004/12/17 20:37UT |
| I=251.5 II=79.6 |
| 40cm Refl. I. Miyazaki |
[Fig.2] |
 |
| 2004/12/24 15:40UT |
| I=169.7 III=230.2 |
| 20cm Refl. K. Yunoki |