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View Full Version : Object of the week July 5. 2015 Lost in Sagittarius Hickson 86



Jimi Lowrey
July 4th, 2015, 09:01 PM
Hickson 86

Sagittarius

Type
Compact Galaxy Group

HCG A

ESO 461-7

RA
19 52 08
DEC
-30 49 33

MAG 14.3
------------------------
HCG B

MCG -05-47-003

MAG 15.3
------------------------
HCG C

MCG -05-47-002

MAG 16.08
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HCG D

MCG -05-47-001

MAG 15.85
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I often ask myself what is a compact galaxy group doing in Sagittarius with all of its star cluster and planetary nebula but its there and a fine example of a compact galaxy group it is! At 315 MLY this group lies well past all the dust and nebula's of Sagittarius. This group is often overlooked with all the DSO's in the area. A good place to start is with M 55 as HCG 86 is just East of this showpiece. I have viewed this group with a 12" scope under dark skies before so it should be in reach for many here on DSF.

1708

Also while you are in the area be sure to try for the challenging object Arp GC 2. This I also have seen in a 12".

Arp 2 GC

Ra
19 28 44
Dec
-30 21 20

"Give it a go and let us know!
Good luck and great viewing!"

Uwe Glahn
July 5th, 2015, 08:03 AM
Nice choice Jimi, especially for those with smaller aperture an obscure objects fans.

I could hold the faintest galaxies in HCG 86 (c+d) with averted vision even despite the low high in the sky here in Germany.
16", 257x, NELM 7m+
1709

Arp 2 was (again because of the low altitude in the sky) a very hard object and was only popping with averted vision as a very faint glow. I first confuse the cluster with a faint star group 18' SW.

16", 100x, Seeing III, NELM 7m+
1710

Howard B
July 8th, 2015, 02:14 AM
Another 20 inch observation, also from 2001:

"Nice group of 4 galaxies a few degrees due west of M55. All four are about equally visible - the magnitude range is 13.7 to 15.0. 261x."

1713 1714

This is a rare digital sketch from me, and not a particularly good one as far as I'm concerned!

My Arp 2 observation is from 2010 with my 28 inch and has a more normal pencil sketch:

"Arp 2 shows itself as a vague, amorphous glow with no internal detail with an indefinite perimeter. 253x, 21.63 SQM."

1715 1716

Steve Gottlieb
July 8th, 2015, 10:10 PM
Arp 2 GC is one of several globulars that may have been captured by the Milky Way from the Sagittarius Dwarf Spheroidal Galaxy, along with Terzan 7, Terzan 8 and several others. It's pretty dim, so I'd be surprised if it was visible in less than a 12-inch, at least from north of +35° latitude. That said, has anyone seen it in an 8" or 10" from at least mid-northern latitudes?

Here's an observation from last July at Lassen National Park at over 8100 ft elevation (with Jimi)

24" (7/25/14): very faint, moderately large, low surface brightness glow, roughly 2' diameter. Contains a small, slightly brighter core or knot near the center. Slightly grainy or mottled appearance, but no clear resolution except around the edges (possibly field stars). Located 5' SW of a distinctive asterism consisting of a 1.5' east-west chain of four stars, with a fifth star 0.4' south of the center of the chain.

Howard B
July 9th, 2015, 10:18 PM
Oops, my Arp 2 observation is the peculiar galaxy, not the globular! I haven't see the globular yet so it's on my list for the GSSP next week.