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It was the good theme whether the STB oval 'BA' yet existed or not existed in early observations of this apparition. 'BA' couldn't be detected in August because the altitude of Jupiter was low ,though the observation began in early August, 2002. It finally became to detect 'BA' with the CCD images on September 2 (UT).
| Observation(UT) | Longitude(II) |
| 2002/09/02 | 359.7 |
| 2002/09/09 | 358.6 |
| 2002/09/19 | 354.9 |
| | Table 1: Longitude of the STB oval 'BA' |
Figure 1 shows the CCD images and the strip maps that are arranged by the position of 'BA'. Also they have the strip map of 2000-01 and 2001-02 apparition in comparison. The images of Hideo Einaga(Hyogo pref.) and Akira Kazemoto(Kyoto) shows the first observation of 'BA' that is very faint. But, 'BA' has no brightness, and it is placed between the dark spot of the STB. Therefore 'BA' didn't get the clear images when the condition was bad on September 9, 19 and 24. Table 1 shows the logitude of 'BA' measured from these images.
Figure 2 shows the drift chart of 'BA' from June, 2000 to September 2002. The oval that was observed in this apparition is distinctly 'BA', because these longitudes are matched with a line expected from the drift of the previous apparitions. The dark section following 'BA' was about 40 degrees length in 2000-01 apparition, and it reduced gradually 15 degrees length in 2001-02. This dark section is further shortened, and it has become a dark spot now. This dark spot is a mark to detect 'BA' because 'BA' exists just before this dark spot. It knows that long-lived STB ovals are bright spots in methane band and are the anticyclonic circulations on the higher atomosphere. I think that the confirmations of methane band is necessary. I expect the future observations.
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