Paddy
27-07-2011, 02:23 PM
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.
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.