Object of the Week, November 20, 2022: Hickson 28 in Eridanus

Compact Galaxy Group of 4 members

RA (brightest galaxy of the group): 04h 27m 18.6s
Dec : -10? 18’ 22”
Size: All 4 members within a 1.7’ circle.
Mag range: 15.9b to 17.8

Apologize for the late post (again) as I was traveling for the last two weeks. I regret to say that I have been pretty inactive in the deep sky community and amateur astronomy in general in the last 5+ years, so to be fair to others and myself, this will be my last contribution to OOTW for the foreseeable future. About 5 years ago, my interest started to slow down, then my last time observing with my 22” was in October 2019. I may be one of the first, if not the first, to visually observe Andromeda’s Parachute and hoped that would get my excitement back. Sadly, it didn’t.

My website will remain up for the foreseeable future, so future deep sky hounds have stuff to download for free and use. I’m glad to see many new deep sky observers coming around as I see names I do not recognize.

One of the main reasons is that I’m in my second stint through grad school, this time not in a STEM field. I already went through that route and my original doctoral studies were on the study of the chemistry of genetic material, centered on gene recognition and modification. This time is something else.

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On to the OOTW, I’m posting from one of my longtime favorite lists, the Hickson Galaxy Groups. This object is a very compact group of 4 galaxies crammed in a 1.7’ space. It is certainly one of the more challenging Hickson groups, but a good challenge even in my 22” reflector under dark skies. I encourage you to give it a shot if you have a 16” or larger telescope.

At 528x, this is a fairly difficult group containing four member galaxies about 1.7’ apart in a crooked N-S line.

Component A (PGC 15136) – This primary galaxy is a very thin, faint spindle with a nearly stellar core. Averted vision gives about 20% more length to a total of 45” long and about 10” wide. Position angle is 170?. A 15.0 magnitude star is about 50” north of the center.
Component B (PGC 15141) – This member is a very faint, very small round spot. Size is about 20” across. It lies about 50” SSE of PGC 15136. PGC 15139 lies less than 20” west of the center; it seems to be attached to the halo.
Component C (PGC 15135) – This member is an extremely faint and very small round fuzzy spot. It is located about 25” due south of PGC 15136.
Component D (PGC 15139) – Re-observation of this group reveals that this “16th” magnitude star noted just to the west of PGC 15141 was actually PGC 15139 (Component D). This appears as a stellar object with very little halo visible at 528x and higher.

Attachment 4927
Labelled DSS image

Attachment 4926
Eyepiece rendition
22” reflector @ 377x, field: 10.3’ NELM: 6.5.

Anyhow, as always, give it a shot and let us know.

Sad to see your temporarily "retirement" Alvin. I call it temporarily because I'm sure that such a gifted astronomer than you returns soon or later. The astronomy fire will always burn, also when you temporarily had other priorities. I hope so.

I noted two observation of the very fine HCG group. With my 16-inch and called the group "very difficult" and only could see an unresolved longish object of a-c.
As you already pointed out my 27-inch noted called the group also "difficult". I had the impression that the given brightness of the single galaxies are to bright. I certainly could catch up all four members but had to work on that very hard. "D" was at my very limit and it only pops out the halo of "B" with difficulties under high magnifications and very good transparency.

sketch: 27", 586x-837x, NELM 7m0+, Seeing II-III
Attachment 4930
home

I, too, am sad to see you go and like Uwe I'm sure you'll be back. Your observing guides have been invaluable to me and have helped me to see many interesting objects in the night sky, so thank you so incredibly much for those!

Having said that, Hickson 28 still is on my TODO list and I'll try to give it a go next time I am in Chile and can use my 20" dob.

I also echo the previous posts. Hopefully, you will return in the future "recharged". Many thanks to you for your observing guides, of which I have and used several. It may have been on a post on this forum that I was first made aware of the Parachute quasar in Andromeda. I was fortunate to have seen 2 of its 4 components at >700x with the 22" from Cherry Springs State Park. It remains one of my top highlights visually!
Alas, I need to downsize from a 22" but I am sure i will still see much with a 15".
Best of luck to you.
Al

Alvin, your observations and your guides have been an inspiration and defined advanced visual astronomy. It was using your guide that I checked off Hickson 28 last month, with only 8 remaining. D eluded me (20", 360x, SQM 21.3 - we were at the maximum of sky brightness). The sketch follows.

Attachment 4931

Alvin--

Your downloadable guides are an exceptional resource for deep-sky observers; I recommend them often, both on CloudyNights and locally. They've been of immeasurable help to me, not just in finding objects but in creating lists of worthy targets, and in getting me to seek further information about those objects you chose to compile. I can't thank you enough.

Good luck in your graduate studies!

Thanks for the kind words. I'm happy that the observing guides are helpful for many and hope to be helpful to future deep sky observers. For sure that I will not take down my site, unless something happens.

I probably will return to deep sky observing, but not until I'm done with my second round of doctoral studies.

I'll still check this site from time to time.

Until later.