The whole situation of SEB event taken place late February has revealed by further observation. At first, it seemed to be partial fading of SEB, as neither rift connecting SEBZ with EZs nor white oval in EZs was observed, though it was suspected some relationship with EZs disturbed region. However, Valimbert's image taken on Mar. 1 and other images by Einaga, Fukui, and Yunoki taken on Mar. 3 show clear rift connecting light band in SEBZ with EZ. Therefore, it became obvious that this event was similar one frequently observed from late 1970s to early 1980s associated with EZs white oval (GWS).

The opening into EZ was prograding much faster than System II, and its rotation period 9h51m15s (+1.1 deg./day), slower than System I, was close to those observed for similar markings in the past. The longitude in System I was 130.5 deg. (Mar. 31, Einaga). Following the rift, northern half of SEB was much disturbed with extremely bluish dark streak interrupted by various sizes of white spots, as if prograding opening into EZ had disturbed SEBn. Such aspect of the belt has not been observed in the events of SEBn rift associated with GWS.

The opening into EZ will encircle the planet early April, and return to the original position, where this event started. In previous events, GWS used to become conspicuous when it had passed RS or SEB active region following RS. It is notable that similar change will take place.

RS was almost stationary at II:90.6 deg. (Mar. 28, Kanno). It was very prominent by orangish tint, with darker core on its center, though weak arch on southern edge and faint streak preceding it remained and narrow band connected its f. end with SEB. Early March, some jetstream spot rapidly moving on STBn passed its southern edge in succession, but they did not affect RS itself. Activity of mid-SEB outbreak following RS had become even quieter, and f. end of the region prograded to about II:135 deg.

BA was at II:151.3 deg. (Mar. 11, Miyazaki), easily seen even by small telescope as large oval with dusky collar. STB was dark and broad between BA and about II:250 deg., though it was somewhat disturbed just following BA. It was followed by oblique chain of irregular dark spots sloping southward and extending to about II:300 deg. Also, narrow STBn was clearly seen between RS and BA. South of STB, SSTB was prominent. It was broader than STB between II:320 deg. and 60 deg., while in other longitude, it consisted of widely separated components, southern one of which seemed to be SSTBs and the other one might be STZB. In SSTB, there were six small white spots in total, five of which were distributed in the range from II:350 deg. to II:90 deg., and the other one was at around II:210 deg.

NEB rift activity was still outstanding, ranging from II:270 deg. to II:20 deg. late March. The other sector of the belt was also active with doubling of the belt and minor activity of white spots. NEBn edge was flat and featureless comparing to that in previous apparitions, but some dark spots projecting into NTrZ were seen at around II:90, 150, and 340 deg. And long-lived white spot on NEBn edge was at II:161.1 deg. (Mar. 13, Kazemoto). NTB was seen as faint streak-like component. As appearance of NT Current-C has not reported yet, observer should pay attention whether brilliant or dark spot is formed on the belt as ever. On NNTBs edge, there were many tiny dark spots rapidly prograding at about -2.5 deg./day along NNTBs jetstream, especially crowded in the range of II:180-240 deg. (late March).

(2) Saturn

Saturn passed eastern quadrature on Mar. 8, and stationary on Mar. 27. It is at last in the final stages of the apparition. This month, we have received observations listed below.

This month, Saturn was quiet and no prominent features were observed. Peach's image taken on Mar. 1 showed faint features at about 40 deg. in latitude and in EZ. He created an animation GIF, in which these were moving with planet's rotation, but these contrast was too low to be tracked by domestic observers.

(April 9, K. Horikawa)

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