Seiichi Yoshida's Diary of Comet Observations (2013)

Japanese version Home page

Updated on April 9, 2013

Detailed observation data in ICQ format.

2013 Apr. 7 (5 comets) I observed 5 comets visually on Apr. 7 on Mt. Tsukuba, Ibaraki, Japan. The sky was fine with no clouds and very clear after the storm. Hard to get in focus with high magnification due to the strong wind. I met several wild boars on the way. C/2006 S3 ( LONEOS ) 13.6 mag   Dia. 0.7'   DC 4   (40.0-cm reflector 144x) Tiny, but easy to find. C/2011 L4 ( PanSTARRS ) 5.2 mag   Dia. 6'   DC 7   Tail 0.4 deg (p.a. 0 deg)   (10x70 monocular) Finally, I could see Comet PanSTARRS. It looks very small, but looks cool with a broad tail. I enjoyed the comet with Andromeda Galaxy in the same field of view. C/2011 R1 ( McNaught ) fainter than 13.0 mag   Dia. 1.6'   (40.0-cm reflector 144x) Maybe a diffuse comet with DC=2 was visible. But I am not sure. C/2013 E2 ( Iwamoto ) fainter than 12.3 mag   Dia. 0.6'   (40.0-cm reflector 257x) Unfortunately, I could not see the comet due to the low sky condition. 273P/Pons-Gambart 13.6 mag   Dia. 1.2'   DC 2   (40.0-cm reflector 144x) Unexpectedly, I could see the comet still now. The comet is very near by Pinwheel Galaxy M101. I also enjoyed the very large diffuse galaxy.

2013 Feb. 15 (2 comets + 1 asteroid) I observed 2 comets and an asteroid 2012 DA14 visually on Feb. 15 on Mt. Tsukuba, Ibaraki, Japan. Although it was rainy in daytime, the sky became completely fine around midnight as the weather forecast predicted. Although Tsukuba City was in the dense fog, the sky was clear on Mt. Tsukuba. So I could enjoy the historical close flyby of an asteroid 2012 DA14. I also tried to observe C/2006 S3, but it was blended with a neaby 12 mag star and I could not oberve. C/2011 R1 ( McNaught ) 12.6 mag   Dia. 1.1'   DC 3   (40.0-cm reflector 144x) Difficult to see because locating near by a pair of double stars, but I could see the comet. 273P/Pons-Gambart 10.8 mag   Dia. 2.1'   DC 5   (40.0-cm reflector 144x) I was filled with deep emotion because finally I could see the long lost comet D/Pons-Gambart. The comet looks well condensed. But anyway, must fainter than I had expected. I had imagined D/Pons-Gambart would be a historical great comet... 2012 DA14 7.1 mag   DC 9   (10x70 monocular) 7.2 mag   DC 9   (40.0-cm reflector 36x) Easy to find exactly at the predicted position. I was observing it during 20 minutes, but the brightness did not change at all.

Go to Seiichi Yoshida's Diary of Comet Observations in 2012.