DescriptionImages

Object name: HCG068

Designation(s): HCG068, NGC350, NGC5353, NGC5354, NGC5355, NGC5358,

Hickson 68 is a galaxy group far larger than apparently Hickson realized. He made the catalog from visual inspection of the Palomar Observatory Survey Plates of the 1950's creating a catalog known as the Hickson Compact Group catalog. Well HCG 68 is not compact. He apparently was only considering the core region. The group is really far larger than my image. It is organized with elliptical galaxies in the center and spiral galaxies mostly on the edges many of which are beyond my FOV. The large spiral NGC 5390 is an example as is UGC 8841 in the lower left corner of my image. The group is located about 115 million light-years away in the constellation of Canes Venatici.

The center is home to the overlapping galaxies NGC 5353 and NGC 5354 which inhabit a common halo. NGC 5353 is an S0 galaxy rather than elliptical that harbors a rather active AGN indicating this might not be a serene old group like it first appears. NGC 5354 to its north is Classes SA0 with strong spectral lines and is a LINER galaxy. Yet more indication this is an active group still in its formative stage. Then there's NGC 5350 a rather classic looking barred spiral. NED classes it SB(r)b while the NGC project says SBb-c. It is a starburst galaxy with intense star formation going on in its core that is hidden from our view by warm dust. Yet another indication of activity.

Other NGC members of the group include NGC 5355, an E3 galaxy by NED and S0? by the NGC Project. NGC 5358 is classed SO/a by both. The other large member of the group in my image is UGC 08841 which is a very nice two armed barred spiral classed by NED as SBb.

NGC 5353 and NGC 5354 appear to share a common halo. It has a very weird sharp cut off at its southern end and appears slightly brighter right before it comes to that sudden end. This is often seen when a dark nebula abuts a bright nebula forming a shock front. I scoured the literature but found nothing addressing this odd feature. Closest I came was an article talking about how this is a still collapsing system with lots of activity to come over the next billion years. http://iopscience.iop.org/1538-3881/135/4/1488/pdf/aj_135_4_1488.pdf

This image is a complete reprocess from the very beginning of data taken back in 2008. When I processed it I included both color and luminance frames taken though clouds which cast a strong gradient across the image, While it was removed much of the halo, including the sharply defined southern end were gone. I through out all these frames and ended up with a much better image that now shows the halo's sudden southern end. Since the color data is weak I am a bit leery of it in faint regions like this halo. If it is right (a very big IF) then the plume has an odd red color as it comes to a halt. This is very weird if true. Is it really gas and dust ejected from the two massive S0 galaxies rather than stars? When galaxies of this size interact most dust and gas is ejected. Is that the source of the southern plume? I'm likely far off base here but what the heck, wild speculation is fun. If anyone finds anything to cut though my wild guesses please let me know and I'll pass it on.

This image was taken with my old, halo prone filters. The bright K5 star really made a mess with my old filters. I left a lot of it in as I found no way to take it out without harming the faint halo around the core galaxies. But compared to the Sloan image of this area I did a much better job with it than they did. I need to reshoot this with more time with the new filters that don't have the halo issue.

The image was taken over 4 nights (one night, while used in the first image was rejected for this one). Many other frames from the other three nights were rejected as well. The result was I am down to my normal 40 minutes of L and 20 for each color. Not what is needed for such a faint feature as the plume, unfortunately. Nor was the night very good. My limiting magnitude is about 21.8 compared to my normal 22.5. That would indicate poor transparency even for the three nights I got usable data. Yet another reason to reshoot it. For now, this reprocess is a great improvement over the original so I'll go with it.

I retook this along with NGC 5371 omitted from this framing. See it for a better image. Unfortunately, it missed the plume.

14" LX200R @ f/10, L=4x10' RGB=2x10'x3, STL-11000XM, Paramount ME

Related Designation(s):

1RXS J135327.3+401658, 2MASS J01015670-0647446, 2MASS J13532670+4016591, 2MASS J13532672+4018101, 2MASS J13534556+4020195, 2MASS J13540042+4016385, 2MASX J01015671-0647444, 2MASX J13532674+4016592, 2MASX J13534556+4020196, 2MASX J13540043+4016387, 2MASXi J0101567-064744, 2MASXi J1353267+401658, 2MASXi J1353267+401809, 2MASXi J1354004+401638, 2XMM J135326.6+401810, 2XMM J135326.7+401659, 2XMM J135345.5+402022, 2XMM J135400.4+401640, 2XMMp J135326.6+401810, 2XMMp J135326.7+401659, 2XMMp J135345.5+402021, 2XMMp J135400.5+401640, 87GB 135118.9+403124, 87GB[BWE91] 1351+4031, APMUKS(BJ) B005925.08-070352.3, ASK 322740.0, ASK 322769.0, CGCG 1351.4+4031, CGCG 1351.4+4032, CGCG 1351.6+4035, CGCG 1351.9+4031, CGCG 219-018, CGCG 219-019, CGCG 219-020, CGCG 219-022, CXO J135326.6+401658, CXO J135326.7+401810, CXO J135326.70+401658.8, ECO 04352, EON J208.502+40.277, FBQS J135326.6+401658, FIRST J135326.6+401658, FIRST J135326.7+401809, GALEXASC J010156.73-064743.5 , GALEXASC J135345.54+402018.2 , GALEXASC J135400.41+401636.5 , GALEXMSC J135345.67+402018.5 , GALEXMSC J135400.44+401636.9 , GB6 J1353+4017, HCG 068, HCG 068A, HCG 068B, HCG 068D, HCG 068E, HCG068, HDCE 0044 NED005, HDCE 0827 NED007, HDCE 0827 NED008, HDCE 0827 NED009, HOLM 555A, HOLM 555B, HOLM 555D, IRAS F13513+4031, KTG 50B, KTG 50C, LDCE 0057 NED006, LDCE 1006 NED010, LDCE 1006 NED011, LDCE 1006 NED012, LGG 361:[G93] 009, LGG 361:[G93] 010, LGG 361:[G93] 017, LGG 363:[G93] 002, LQAC 208+040 004, MAPS-NGP O_221_0299269, MAPS-NGP O_221_0315550, MCG +07-29-010, MCG +07-29-011, MCG +07-29-012, MCG +07-29-013, MCG -01-03-069, NGC 0350, NGC 5353, NGC 5353:[L2011a] X0001, NGC 5353:[LB2005] X01, NGC 5354, NGC 5354:[L2011a] X0001, NGC 5355, NGC 5358, NGC350, NGC5353, NGC5354, NGC5355, NGC5358, NPM1G -07.0040, NSA 056480, NSA 056483, NSA 056488, NSA 144021, NSA 153838, NVSS J135326+401658, NVSS J135326+401812, PCC N79-286, PGC 003690, PGC 049354, PGC 049356, PGC 049380, PGC 049389, RSCG 71, RX J1353.5+4016, SDSS J135326.72+401659.4, SDSS J135345.56+402019.2, SDSS J135400.41+401638.3, SSTSL2 J135326.68+401658.7, SSTSL2 J135326.69+401809.8, SSTSL2 J135345.57+402019.3, SSTSL2 J135400.46+401639.0, UGC 08813, UGC 08814, UGC 08819, UGC 08826, USGC U578 NED07, USGC U578 NED08, USGC U578 NED09, USGC U578 NED10, UZC J135326.7+401659, UZC J135326.8+401808, UZC J135345.6+402019, UZC J135400.4+401639, WBL 475, WBL 475-002, WBL 475-003, WBL 475-004, WBL 475-005, [H84a] 1351+405.2, [JBB2007] J135326.69+401658.8 , [KOS87] 135118+403154, [KOS87] 135118+403300, [KOS87] 135137+403500, [M98j] 206 NED10, [M98j] 206 NED11, [M98j] 206 NED12, [MGD2014] 1351.3+4031, [TT2008] 002, [TT2008] 003, [TT2008] 012, [TT2008] 016, [VCV2006] J135326.7+401659, [WGB2006] 135118+40360_b, [WGB2006] 135118+40360_c,