Earlier this week I observed IC 1613 with my 16” from our club site. Following the passage of clouds the sky cleared beautifully, and for the first time in months it was almost bracing at night. IC 1613 was visible at 45x with the Pentax XW40 and displayed the bar and possibly the large NE star cloud, the features that I saw with my 12” SCT two years ago. At 225x with the 8-mm Ethos the galaxy immediately showed some intricate detail at the E end of the bar. I felt compelled to abandon my observing plan and remained on IC 1613 through culmination, 01:00-03:00, completing the sketch by 04:00. At culmination the area measured 21.28 mag/sq arcsec by SQM-L, not terribly dark but apparently dark enough. Zeiss Abbe II 6 mm (300x) did not improve the view; in fact I lost many details in the narrow field.
There was a bright star in an unexpected position and I considered the possibility of a supernova, but later determined it to be the classical asteroid Nysa (m10.5).
Stellar associations (A), HII regions (H), and dark nebulae (D) are labeled on the sketch according to the Hodge Atlas of the Local Group. The labels list components in the E-W order and minor components in brackets. The field drawn is that of the Ethos, 1/2 degrees. One pencil arrow indicates the “supernova”, the other the place of the brightest star nearest to that position that was not seen.
EDIT: Our forum system (when it so decides) does some additional compression on attached images, which is not optimal. Below is my sketch referenced externally:
Last edited by Ivan Maly; October 3rd, 2013 at 12:57 PM.
I've never been able to so much as get a glimpse of this galaxy from my northern outpost, not to mention seeing any kind of detail. This observation is awesome.
Thank you, Thomas - I think it had to do with unusual sky conditions immediately in the wake of a cloud front. The Canadian astronomy forecast we use here said transparency above average to average, but I believe it was markedly better, something not revealed by the SQM. What also helped is that I saw at least a little detail before, so I generally knew what was where in this galaxy's field. It was a shock though when such fine detail began to appear almost immediately. I am still under big impression from that observation. The name of the game in this hobby seems to be to keep looking. Unusual conditions happen and galaxies just explode in unexpected detail.
I am placing this IC 1613 observation somewhere with my one-time view of ridiculously contrasty dust lanes splitting the arms in M51 - not just little dark segments here and there but pretty much all along the two arms save for where bright enhancements ("HII regions") interfered too badly. That night also my expectations were very low but the iffy weather conditions we were having worked out beautifully. This time, it is funny to remember now, I had doubts I would be able to see IC 1613 at all, attempting it for the first time from our rural but noticeably compromised club site.
Another thing that occurs to me is that maybe the pleasant but longish drive to my usual remote site 3 times farther into the sticks may be taking a toll on my vision. I will try going more often to the club site and see if this might be a factor.
Last edited by Ivan Maly; September 6th, 2013 at 06:09 PM.
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