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Old 27-07-2011, 02:23 PM
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Paddy (Patrick)
Canis Minor

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Join Date: Jun 2007
Location: Strangways, Vic
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A few Globulars and an OC 22/7/11

Had a little observing through moist skies last Friday. Transparency was poor, so I thought "GCs" and still included a couple of fainter ones.

Here are my notes.

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 NGC/IC project, SEDS list of galactic GCs, http://seds.org/messier/xtra/supp/mw_gc.html

2030

Seeing good, transparency fair – lots of high altitude moisture so bright stars have something of a halo

Lynga 7 GC in Norma
16:11:03.65 -55:19:04.0
Vmag 10.8

175X Next to a bright foreground star and y shaped asterism. This faint haze is just discernible against the busy background sky. Is quite round and looks about 3’ across.

(notes from SEDS http://spider.seds.org/spider/MWGC/lynga7.html
Discovered 1964 by G. Lynga.
Recognized as globular cluster in 1993 by Ortolani, Bica and Barbuy.

Globular cluster Lynga 7 was first cataloged by G. Lynga (1964) as open cluster and classified as of Trumpler type II 2 p. It is listed again as open cluster by van den Bergh-Hagen (1975) as vdB-Ha 184.

It was only in 1993 that Ortolani, Bica and Barbuy brought up evidence that this object might be a globular cluster. They investigated its color-magnitude diagram, which resembles that of a globular, but derive a significantly lower age than for the usual globular clusters, and classify it as a disk globular cluster. Similar results were obtained by Tavarez and Friel (1995). Meanwhile, Lynga 7 is generally regarded as globular.

Lynga 7 is one of the more "metal-rich" globulars, i.e. its stars contain significantly higher concentrations of elements heavier than Helium than average globulars, more similar to the composition of our Sun.

NGC 6067 OC in Norma Trumpler class I 3 r
16h 13m 11.0s -54º 13' 06"
Vmag 5.6 Dia 12’

135X Just the other side of Kappa Normae from Lynga 7, this is a very distinct spray of about 100 stars with a very nice bright pair right in the middle and lots of interesting lines and asterisms. The brightest of the pair is yellowish and the slightly fainter partner is blue. Quite a bit of variation in stellar magnitudes, but none that are really bright. Elongated p-f and stands out well against the star field and is quite obvious in the finderscope. In the centre is a starfish-shaped dark patch.


Pismis 26 GC in Scorpius
17:36:10.5 -38:33:12
Vmag 12.2 Dia 2.2’

175X A faintly discernible circle of haze sitting in a little triangle of stars about 2’ dia.

NGC 6544 GC in Sagittarius Class V
8h 07m 20.5s -24º 59' 51"
Vmag 7.5 Dia. 8.9

175X Quite a pretty GC moderately concentrated in a busy field with some stars just resolvable and many on the edge of resolution. On the preceding side is a N-S arc of stars (convex preceding) and another to the following side. So the star field is quite beautiful, but it’s a little hard to find the edge of the GC amongst it.

A tad over 1’ to the east is

NGC 6553 GC in Sagittarius Class II
18h 09m 17.5s -25º 54' 28"
Vmag 8.3 Dia 9.2

175X Looks a little larger to my eye than neighbouring 6544 and in a quieter field. There is a bright star at the preceding edge. The GCs glow is very even, very round with no marked core but overall very concentrated with no resolved stars.
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