Seiichi Yoshida's Diary of Comet Observations (2026)

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Updated on August 25, 2026

Detailed observation data in ICQ format.

2026 Aug. 22 (1 comet) I observed 10P visually on Aug. 22 in Mt. Hakkaisan, Niigata, Japan. We could observe 10P/Tempel 2 at the star party of annual comet conference in Japan with many other Japanese comet observers. Unfortunaely, clouds covered the whole sky just after 220P/McNaught rose up from the Mt. Hakkaisan. I could see 220P/McNaught in a short time, but I could not observe it. 10P/Tempel 2 8.4 mag   Dia. 6'   DC 3   (40.0-cm reflector 36x) Central condensation was well visible with a higher magnification.

2026 Aug. 18 (2 comets) I observed 10P and 220P visually on Aug. 18 in Mt. Tsukuba, Ibaraki, Japan. 10P/Tempel 2 7.9 mag   Dia. 5.5'   DC 0-1   (40.0-cm reflector 75x) Hard to see due to thin clouds and city light of Tokyo. 220P/McNaught 8.4 mag   Dia. 2.8'   DC 2   (40.0-cm reflector 75x) Finally I could see this comet. It looks bright still now.

2026 Apr. 16 (1 comet) I observed C/2025 R3 visually on Apr. 16 in Mt. Tsukuba, Ibaraki, Japan. Finally I could observe C/2025 R3 ( PanSTARRS ). C/2025 R3 ( PanSTARRS ) 4.8 mag   DC 8-9   (10x70 monocular) Very sharp, looks almost stellar with a lower magnification. It also looks strongly condensed and sharp even with 0.40-m reflector.

Go to Seiichi Yoshida's Diary of Comet Observations in 2025.