Beautiful trio with Comet 67P Churyumov-Gerasimenko

Comet 67P Churyumov-Gerasimenko is probably just about an average periodic comet. It never gets particularly bright, so it would have gone unnoticed to the general public, were it not for the fact that it was the target of the Rosetta spacecraft, which it reached with a close fly-by in November 2014 and managed to launch a lander on the surface of the comet’s nucleus. In addition to improving our understanding of cometary structure and behavior in general, the Rosetta mission probably made 67P the best-known and most studied comet ever.

Comet 67P has a period of about 6.5 years, so it was due to make another comeback to the inner solar system since its 2015 perihelion that made the Rosetta mission possible. Comet 67P reached perihelion on 2 November 2021, and has been rather well-placed for observers in the northern hemisphere.

Along its journey in the night sky, comet Churyumov-Gerasimenko 67P “grazed” several deep-sky objects. One such close encounter not to be missed was the one with two well-known open clusters in Gemini, Messier 35 and its dimmer neighbor NGC 2158. The triplet was expected to put on a really nice show in the wee hours of 16th October 2021.

In the morning of 16th October 2021 the sky was clear, so I just couldn’t pass up this opportunity!  I imaged the triplet when the comet was about 25 arcminutes northwest of M35. I took fifty two-minute exposures over a timespan of about two hours, during which the comet can be seen drifting slowly from right to left in the field of view.

I also made a short video showing the comet zipping past the two well-known open clusters: