Director: K. Horikawa, Secretary: Y. Iga
Jupiter was seen in southern sky at evening, passing eastern quadrature on Oct. 6. This month, we received observations listed below.
| Observer | Location | Telescope | Images/Drawings | |
|---|---|---|---|---|
| Akutsu, Hiroaki | (Hokkaido, Japan) | 28cm Refl. | 32 | images |
| Akutsu, Tomio | (Philippines) | 35cm SCT | 31 | images |
| Asada, Hideto | (Kyoto, Japan) | 31cm Refl. | 37 | images |
| Einaga, Hideo | (Hyogo, Japan) | 30cm Refl. | 40 | images, 17 maps |
| Fukui, Hideto | (Shizuoka, Japan) | 35cm SCT. | 3 | images |
| Go, Christopher | (Philippines) | 28cm SCT | 2 | images |
| Hayashi, Toshio | (Kyoto, Japan) | 35cm SCT | 9 | images |
| Horikawa, Kuniaki | (Yokohama, Japan) | 16cm Refl. | 5 | drawings |
| Ikemura, Toshihiko | (Nagoya, Japan) | 38cm Refl. | 10 | images |
| Kanno, Seiichi | (Yamagata, Japan) | 25cm Refl. | 3 | images |
| Kazemoto, Akira | (Kyoto, Japan) | 31cm Refl. | 9 | images |
| Kumamori, Teruaki | (Osaka, Japan) | 20cm Refl. | 19 | images |
| Mishina, Toshiroh | (Yokohama, Japan) | 20cm Refl. | 2 | images |
| Narita, Hiroshi | (Kawasaki, Japan) | 20cm Refr. | 27 | drawings |
| Phillips, Jim | (USA) | 20cm Refr. | 1 | image |
| Yoneyama, Seiichi | (Yokohama, Japan) | 20cm Refl. | 6 | images |
| Yunoki, Kenkichi | (Osaka, Japan) | 26cm Refl. | 28 | images |
After the long activity more than half a year, it seemed that mid-SEB outbreak ceased at last. The gush of white clouds halted at the source region preceding RS, where activity had lingered on. Though light band remained between II:270 and 20 deg., it was narrower and less disturbed. Two small white spots appeared in mid-October in the second source region of outbreak at around II:210 deg,, which halted activity last month. These were considered to be aftereffects of outbreak. On SEBs edge adjacent to the south of spots, dark spot developed largely near the end of October.
RS kept the aspect of Hollow. Though reddish body of RS was seen inside of Hollow, dark blue surroundings were very conspicuous without any sign of weakening. It was at II:129.6 deg. (Oct. 15, Kumamori), and was retrograding slowly. Dark streak preceding RS was merging with another streak which was previously formed along SEBs edge. As a result, it became difficult to distinguish them. The streak was continuous up to II:350 deg., and fragments and spots which the streak broke into extended to about II:270 deg. It may have started to decline, since the streak was fainter preceding II:90 deg. in late October.
BA prograded to II:67.7 deg. (Oct. 31, Akutsu), and large STZ dark oval following BA passed south of RS. It was noted that it became outstanding just after passage, but it was transient. A lot of tiny spots which was rapidly prograding with STBn jetstream were observed preceding BA.
EZ was still light, but it seemed that more bluish filaments increased than before. In NTBn, irregular bluish markings, which were prominent from last month, turned into distinct component of the belt between II:160 and 230 deg. this month. Further north, NNTB was reviving, and distinct belt segments were formed at II:340-70 deg. and 150-230 deg.
Saturn came to appear in east sky before sunrise, as a little more than one month has passed since solar conjunction. Though condition was still poor, we received observations from eager observers.
| Observer | Location | Telescope | Images/Drawings | |
|---|---|---|---|---|
| Ikemura, Toshihiko | (Nagoya, Japan) | 38cm Refl. | 2 | images |
| Kumamori, Teruaki | (Osaka, Japan) | 20cm Refl. | 3 | images |
| Takimoto, Ikuo | (Kagawa, Japan) | 31cm Refl. | 1 | image |
| Yoneyama, Seiichi | (Yokohama, Japan) | 20cm Refl. | 2 | images |
| Yunoki, Kenkichi | (Osaka, Japan) | 26cm Refl. | 1 | image |
The tilt of the ring has fallen below -3 deg., much decreasing during solar conjunction. It was difficult to see details of the ring, since it was thinly squashed in every image.
In August and September of 2009, near the end of this apparition, the disappearance of the ring takes place. The tilt of the ring will decrease to -0.8 deg. at year end, but it turns to increase next year, and will reach maximum of -4.1 deg. in May. The disappearance of the ring will be under poor condition, because it takes place just before solar conjunction. Therefore, year-end is suitable for observation of narrow ring.
(November 14, K. Horikawa)
(Translated on June 22)