Comet C/2012 V4 at magnitude 9.4
December 8, 2012 3 Comments
Last evening (Dec. 7 UT) the sky was finally free of cirrus and I was able to see newly discovered comet C/2012 V4, the first probable return of Comet Pons-Gambart since 1827. This evening (Dec. 8.06 UT) I was able to spot the comet again using Mars as a guide since the two bodies are within a few degrees of each other.
In short, this was a very difficult comet to observer. It was invisible in my 30×125 binoculars and I could only see it with averted vision in a 12″ dobsonian. Though the sky is relatively dark at my house (Milky Way always visible and LM of ~+6.0), the comet was located within 10° of the horizons and in the direction of the skyglow from Tucson. I estimated a brightness of 9.4 and a coma 1′.5 across. If C/2012 V4 were located overhead it wouldn’t have been a problem. For example, 168P which was also around magnitude 9.4 in early October was visible in 10×50 binoculars but it was much higher and located away from city lights.
Unless the comet undergoes a rapid brightening soon it will only get harder to observe as its elongation slowly decreases.