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Old 28-06-2011, 08:33 PM
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Paddy (Patrick)
Canis Minor

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Join Date: Jun 2007
Location: Strangways, Vic
Posts: 2,208
Globulars 27/6/11

Another clear night last night and a chance to chase down some of the globulars in Scorpius, Sagittarius and Ophiuchus. Armed with Uranometria and some printed DSS images I go looking for the faint ones. I have found that even when I know I'm in the right place, knowing which bit of faint fuzz is the target GC is challenging and I found the DSS images very helpful. There is no way I could tell otherwise and how anyone identified some of these as possible GCs in the first place is utterly beyond me. I intermittently rewarded my patience with some bright GC as well. Fortunately the transparency was little better than it has been for some time. Thanks for reading.

Telescope 410mm (16”) f4.9 tri-dob reflector
Eyepieces 28mm UWAN, 17,13,9 mm Naglers, Paracorr
Navigation: Night Sky Observer’s Guide (NSOG), Uranometria Vol 2
Data from SEDS list of galactic GCs http://seds.org/messier/xtra/supp/mw_gc.html

The plan – globulars around Scorpius, Sagittarius and Ophiuchus, especially some of the fainter ones.

2030

Seeing good 2/5
Transparency fair – some high altitude moisture – 6th mag stars in Coal Sack just discernible. The Emu is obvious but with a little less contrast than usual

ESO 452-SC11 GC in Scorpius
16:39:25.45 -28:23:55.3
Vmag 12 Dia 1.2’

175X Really need the DSS image of this GC to be able to pick it. Very faint behind a few faint foreground stars forming a NW-SE line across the front of the GC. Size is hard to estimate due to faintness

Terzan 3 GC in Scorpius
16:28:40.08 -35:21:12.
Vmag 12.00 Dia 3.0’

175X Again hard to pick without DSS image as there is so much fuzzy stuff in the field. There is a foreground star in front of a faint halo which could be about 2’ across.

NGC 6266 Messier 62 GC in Ophiuchus
17:01:12.80 -30:06:49.
Vmag 6.45 Dia 15.0

175X A stunning, bright GC. Quite an interesting shape – a strong core is more to the south of the GC and the northern part of the GC widens away from the core so that the GC looks a bit like a wide tailed comet. Many resolvable stars. To the west is dark nebula Barnard 241

http://spider.seds.org/ngc/ngcdss.cgi?obj=NGC!6266!=!M62&r=17: 01.2&d=-30:07&e=J2000&h=16.92&w=16.92&f=GIF &c=none

NGC 6304 GC in Ophiuchus
17:14:32.25 -29:27:43.3
Vmag 8.22 Dia 8.0

175X Quite a bright GC, well concentrated with grainy texture of stars on the edge of resolution. The core looks elongated slightly NW-SE. No strands of stars or haze pulled out from GC. Looks about 4’ across and the core about 2’

http://spider.seds.org/ngc/ngcdss.cgi?obj=NGC!6304&r=17:14.5&d =-29:28&e=J2000&h=15&w=15&f=GIF&c=non e

Terzan 4 GC in Scorpius
17:30:39.00 -31:35:43.9
Vmag 16.00 Dia. 0.7

175X Very faint and small (30”) glow behind faint star.

Terzan 2 GC in Scorpius
17:27:33.10 -30:48:08.4
Vmag14.29 Dia. 0.6

175X Near a little trapezium of stars, this is a very faint glow with some foreground stars in front of it.

NGC 6624 GC in Sagittarius
18:23:40.51 -30:21:39.7
Vmag 7.87 Dia. 8.8

175X A beautiful little GC with marked core, very regular round halo and some distinct stars over the halo. The brightness of the core diminishes abruptly to the soft halo. Looks about 4’ across.

http://spider.seds.org/ngc/ngcdss.cgi?obj=NGC!6624&r=18:23.7&d =-30:22&e=J2000&h=15&w=15&f=GIF&c=non e

Visits to a few bright favourites make a nice end to the evening.
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