Object of the Week February 14, 2016 - NGC 2329 and the Abell 569 Cluster of Galaxies

Object of the Week February 14, 2016 - NGC 2329 and the Abell 569 Cluster of Galaxies

This week’s OOTW is guest authored by Deep Sky Forum member Mark Stuart. Mark observes from near Bristol in the UK and is a member of the Bristol Astronomy Society. His primary instrument these days is a 16-inch Meade Lightbridge. A long time deep sky observer, Mark’s passion is the visual observing of galaxies. He has observed over a 1000 galaxies and he continues to add to his list at every opportunity. He maintains a list of these galaxies on his web site at www.bristolweather.org.uk/galaxies/Deep_sky_galaxy_list.html .

NGC 2329, MCG 8-13-73, UGC 3695, PGC 20254
Type: Elliptical Galaxy
Class: E-S0
Constellation: Lynx
RA: 07h 09m 0.8
Dec: +48’ 36”
Size: 1.3' x 1.1'
Magnitude: 12.7

ACO 569
Type: Galaxy Cluster
Constellation: Lynx
RA: 07h 09m 12s
Dec: +48’ 37”
Size: 56’


Lynx is not one of those constellations that gets a lot of attention. Most people know of the bright spiral NGC 2683 and the distant globular NGC 2419 but that’s about it. When you look towards Lynx you are looking out in to deep space above the Perseus arm of our spiral galaxy. It is well placed for viewing from the Northern hemisphere from early Winter to early Summer.

Attachment 1994
Deep Sky Survey of the AGO 569 Centered on NGC 2329

At first sign NGC 2329 looks like a pretty normal elliptical galaxy but it is a special one. It is a massive elliptical giant spewing out jets of gas and x-rays and the like. It anchors the relatively unknown galaxy cluster Abell 569 which lies at a distance of 250 million light years away. Abell 569 is a large cluster, over 100 million light years across which contains 85 galaxies listed here on Simbad.

This cluster is apparently connected with the Pisces Perseus wall of galaxies. Here is the cluster plot which gives you some sense of the cluster.

Attachment 1997

I discovered NGC 2329 for the first time on the 23rd December 2011 with my 10-inch Skywatcher Dob. I noted it as a very small round faint galaxy which required averted vision to spot. At the time I did not realize how special it was.

I went back to the area on the 7th January 2016 with my 16 inch Meade to have a look at UGC 3696. It was a small oval galaxy but did require averted vision to spot. NGC 2329 was in the same field of view. Here is my original observation.

Attachment 1996

After discovering UGC 3696 and NGC 2329 were both members of Abell 569, I looked back to see if I had seen any other group members. It turns out I had observed NGC 2320 / NGC 2322 / NGC 2340 and MCG 8-13-61.

So have a look again at this area next time you are out and see how many members of the group you can see.

Give it a go and let us know!

Excellent pick for the OOTW, Mark.

Here are objects I've seen with my 18" within about 20' of NGC 2329. I've gone through the cluster a couple of times, most recently in January of 2007. I've also observed several galaxies further afield (like the NGCs you mentioned) as well as a small triplet about 40' south (KTG 14) that shares a similar redshift so is probably part of the same cluster or supercluster.

2MASX J07072766+4840189 = PGC 2322855
07 07 27.7 +48 40 19
B = 16.2; Size 0.4'x0.4'

18" (1/13/07): very faint, very small, 15" diameter, low surface brightness but definitely pops out often with averted vision. Located 5' W of MCG +08-13-061 and 4.4' SW of mag 9.3 SAO 41571.
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MCG +08-13-061 = CGCG 234-059 = PGC 20209
07 07 59.6 +48 39 59
V = 13.5; Size 1.0'x1.0'; Surf Br = 13.3; PA = 51d

18" (1/13/07): possibly the third brightest galaxy in AGC 569. Appeared fairly faint, slightly elongated, 0.6'x0.5', weak even concentration with a small brighter core and faint stellar nucleus with direct vision. Located near on the west side of the cluster with 2MASX J07072766+4840189 5' further west.
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MCG +08-13-071 = CGCG 234-068 = PGC 20243
07 08 52.7 +48 27 00
B = 15.2; Size 0.6'x0.35'; PA = 83d

18" (1/13/07): faint, small, elongated 3:2 WSW-ENE, 0.4'x0.25'. A wide pair of mag 12 stars lies 0.8' NE and 1.4' NW on the south end of AGC 569.
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MCG +08-13-072 = CGCG 234-069 = PGC 20246
07 09 03.6 +48 34 24
V = 15.1; Size 0.5'x0.4'; Surf Br = 13.2; PA = 135d

18" (1/13/07): extremely faint, very small, round, 0.3' diameter. Definitely pops in an out of view with averted vision but cannot hold continuously. Collinear with two stars to the WNW.
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NGC 2329 = UGC 3695 = MCG +08-13-073 = CGCG 234-070 = PGC 20254
07 09 08.0 +48 36 55
V = 12.5; Size 1.3'x1.1'; Surf Br = 12.7; PA = 175d

18" (1/13/07): moderately bright, fairly small, elongated 3:2 N-S, 0.8'x0.5', small bright core. Brightest in the core of AGC 569 including UGC 3696, MCG +08-13-072 and +08-13-082.

18" (11/18/06): moderately bright, moderately large, oval 4:3 N-S, 1.2'x0.9', contains a large, brighter core. This galaxy and UGC 3696, located 2.8' NE, are the brightest member of AGC 569.
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UGC 3696 = MCG +8-13-077 = CGCG 234-073 = PGC 20268
07 09 23.1 +48 38 07
V = 12.8; Size 1.0'x0.6'; Surf Br = 12.4; PA = 77d

18" (1/13/07): fairly faint, fairly small, elongated 2:1 WSW-ENE, 0.6'x0.3', very small bright core. A faint mag 15 star is at the east end. Forms the west vertex of an isosceles triangle with two mag 11/12 stars to the NE and SE.
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MCG +08-13-082 = CGCG 234-078 = PGC 20283
07 09 44.8 +48 41 26
B = 15.4; Size 0.6'x0.6'

18" (1/13/07): faint, small, irregularly round, 0.3' diameter. Contains a faint quasi-stellar nucleus surrounded by a very low surface brightness halo.
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MCG +08-13-087 = PGC 20307
07 10 33.9 +48 38 02
B = 16.1; Size 0.5'x0.4'; PA = 138d

18" (1/13/07): at first I picked up a very faint 15.5 magnitude star close to the plotted position of the galaxy and I thought it might be the nucleus, but it appeared completely stellar. Then occasionally I got a brief glimpse of an extremely faint glow to the SW of this star. Checking the DSS at home, this position is exactly where the galaxy is located in relation to the faint star.
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CGCG 234-089 = PGC 20330
07 11 00.6 +48 41 12
B = 15.0; Size 1.0'x0.3'; PA = 40d

18" (1/13/07): very faint, small, extremely thin splinter of light, 20"x5", oriented SW-NE. A mag 12 star is embedded at the SW tip.
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I have an observation of Abel 569 from 2007 with my 28 inch scope:

"Now this is a terrific galaxy cluster! Two curved arcs of galaxies give this group a unique look, and it's great fun to soak in. It took forever to find but the view was worth the search. 192x to 297x."

Attachment 2004 Attachment 2005

Thank you Steve and Howard for your responses to my OOTW.


I am now inspired to look for other less well known targets.

Mark

I've rotated Howard's sketch 180° so north is roughly up and hopefully labeled the galaxies correctly.

Attachment 2007

Thanks Steve, much better!