Type: Compact Galaxy Group
Constellation: Pisces
Central position: 23 47 23 -02 19 34 (2000)
Members: 5+
Distance: ~300 million l.y. (z = .022)
HCG 97.SDSS.jpg
If you enjoy observing compact groups, HCG 97 presents 5 galaxies ranging from V = 13.0 to 15.6 and presents a nice challenge for a range of apertures. Furthermore, it's the brightest of the 377 Shakhbazian compact groups of compact galaxies (Shkh 30).
The main quintet was discovered by E.E. Barnard on 28 Oct 1889 at Lick Observatory. At the time, Barnard was observing Brooks Comet (1889V) with the 36-inch Clark refractor. He didn't publish the discovery, though, until 1906 while he was at Yerkes Observatory. His sketch (below) clearly identifies all 5 members of the quintet. Don't try to match up Barnard's letter designations with Paul Hickson's - there's no correlation. Also note his sketch has south up, so you'll need to mentally rotate it 180° to match the SDSS image.
The Shakbazian numbering goes deeper and includes 6 through 11 as well as A through D, (letters added later), for a total of 15 galaxies. One or more of these, though, may be background galaxies.
Barnard sketch.jpg
All 5 members of HCG 97 are visible in an 18" scope in good conditions, though one is tough. The brightest member is 13th magnitude IC 5357 = HCG 97A = Shkh 30-1. I recorded it in my old 18" as "moderately bright, elongated 4:3 NNW-SSE, 0.8'x0.6', broad concentration. Located 3' NW of a mag 10.5 star (with IC 5351 attached)."
IC 5359 = HCG 97B = Shkh 30-5 is a thin edge-on and fainter than you'd expect for the "B" component. It was quite a dim streak in my 18", about 50" in length with a very low, uniform surface brightness. Interestingly, Barnard didn't sketch it as an edge-on in the 36-inch. It's marked with a "K" on his sketch.
IC 5351 = HCG 97D = Shkh 30-2 is interesting because it's attached on the north side of a 12th magnitude star, which partly masks the galaxy! You might also see the nucleus of the galaxy if its not washed out by the star.
The faintest member (15.6V) of the quintet is IC 5352 = HCG 97E = Shkh 30-4, which was a threshold object in my 18". I took a look at it two weeks through my 24-inch and still there was no details. Just a small, round 12" patch. Hickson failed to identify his HCG 97E as IC 5352, and this omission is continued today by HyperLEDA and SIMBAD.
Besides the quintet, there are a couple of MCGs about 12' SE (MCG -1-60-40 and -41) that you should also check out (-41 is easier). And in excellent conditions - and large enough aperture - it might be possible to glimpse one of the much fainter Shkh members. Barnard mentioned "there are probably a number more nebulae here." He was right!
This labeled image is from Rick Johnson, who passed away earlier this year, and often posted his images of obscure galaxies and groups on CloudyNights.
RJ2.jpg
As always,
"Give it a go and let us know!
Good luck and great viewing!"
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