Director: K. Horikawa, Secretary: Y. Iga
Jupiter was at solar conjunction on Jan. 24. The last observation in 2008 apparition was reported.
| Observer | Location | Telescope | Images/Drawings | |
|---|---|---|---|---|
| Fukui, Hideto | (Shizuoka, Japan) | 35cm SCT | 1 | image |
Fukui's image was taken on Jan. 4. It was only 20 days before solar conjunction, and altitude of Jupiter at sunset was 12 deg. In spite of the poorest condition, his image showed distinct NEB and SEB with light EZ. Somewhat dusky STrZ following CM might be because dark streak preceding RS had not faded away. BA was not confirmed in the image. Slightly wavy SEBn edge might be disturbed region in EZs (SED).
Saturn passed stationary on New Year's Day, and turned to retrograding motion. It entered into good period for observation. This month, we received observations listed below.
| Observer | Location | Telescope | Images/Drawings | |
|---|---|---|---|---|
| Akutsu, Tomio | (Philippines) | 35cm SCT | 24 | images, 2 animations |
| Fukui, Hideto | (Shizuoka, Japan) | 35cm SCT | 8 | images |
| Go, Christopher | (Philippines) | 28cm SCT | 4 | images, 3 animations |
| Ikemura, Toshihiko | (Nagoya, Japan) | 38cm Refl. | 2 | images |
| Kumamori, Teruaki | (Osaka, Japan) | 20cm Refl. | 7 | images, 2 animations |
| Nakai, Kenji | (Hiroshima, Japan) | 25cm MCT | 1 | image |
| Pellier, Christophe | (France) | 25cm SCT | 9 | images |
| Tyler, Dave | (UK) | 28cm SCT | 1 | image |
| Wesley, Anthony | (Australia) | 33cm Refl. | 3 | images, 1 animation |
| Yoneyama, Seiichi | (Yokohama, Japan) | 20cm Refl. | 5 | images |
| Yunoki, Kenkichi | (Osaka, Japan) | 26cm Refl. | 18 | images |
The tilt of the ring, which had passed local minimum late December, hardly changed between -0.8 deg. and -1.3 deg. this month. But the ring opened a little at the end of the month, when thin dark space inside the ring was seen on both side of Saturn's body.
A white spot in southern STrZ, notified in the last report, was not observed this month. Some images by Akutsu and Go showed a dim portion, but it is not certain whether it was a true spot or noise.
By the way, a noticeable white spot appeared in northern EZ. The first observation was made by Pellier as tiny bright spot at about I:80 deg. in narrow EZn between shadow of the ring and NEBs edge. It was clearly seen also in Kumamori's image on Jan. 6, and Akutsu's images on Jan. 8. The spot was tracked since then, and images on Jan. 23 by Akutsu and Go showed it beside Titan which was in a transit across the Saturn's disk. Its longitude was over I:100 deg. at that day.
On the opposite side of the ring, dusky shadings were observed along SEBn edge. In Kumamori's image on Jan. 7, a festoon-like marking was seen extended toward EZs from SEBn edge at about I:310 deg. A similar marking was also seen at about I:120 deg. in Akutsu's image. Because both longitudes were widely separated, there may be some of such markings. Appearance of dusky marking was noteworthy, since most activities on Saturn in recent years were by white spots.
White spots were also observed in other area, mainly SEBZ. It was suggested that Saturn was active.
This month, transits of Titan across Saturn's disk were observed on Jan. 7 and 23, and it appeared as a large dark spot like Galileo satellite of Jupiter. The transit of Titan is rare phenomenon which is observed only when the tilt of the ring is near zero. Since a few more transits take place in March, it will become good target for observation.
(February 13, K. Horikawa)
(Translated on September 26)