Old 24-01-2010, 06:18 PM
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barx1963 (Malcolm)
Bright the hawk's flight

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Observing Report 23-24/1/10

Observing Report 23-24/1/10
Observations made from Colac Vic. Commencing at 11-30pm to 1-30am. Very dark and cold (5 degrees C)
All observations made using Dobsonion mounted 305mm Newtonian reflector at f/5. Eyepieces use are 32mm (47x) 24mm Panoptic (67x) 13mm Nagler T6 (115x) or 13mm Nagler with Barlow (230x)
Charts Uranometria 2000 (2nd ed.)
NGC 5286 (Caldwell 84, Hartung 541)
Date 23/1/10 Seeing - Fair
Globular Cluster in Centaurus

Locate Epsilon Centauri which is naked eye star pointing from Hadar towards Omega Centauri about 10o Np from Hadar. This star forms the point of a right angle triangle with Gamma and Zeta Centauri. Proceeding from Epsilon Centauri to Nf about 1/3 of distance to Zeta Centauri is star M Centauri which has an orangey tint, however that may be caused by its low position at this time of year. M Centauri is also a binary, will follow up this observation at a later date. NGC 5286 is in same field as M Centauri.. The stars 4.6 mag glare dims the cluster by contrast. Nevertheless, target is still fairly large and bright.
Condensation of this cluster is minimal with a fairly even brightness to nearly its edge. Core is only slightly brighter. Probably would appear larger if a more isolated position as faint outlying stars would be more apparent.
This is one of the ancient clusters that caused much discussion in recent years when studies of its stars indicated an age of 13-18 billion years with the most probable figure being around 17 billion, yet the Universe was only believed to be around 12 billion years old. Follow up studies have since reconciled this discrepancy, but nevertheless we are looking at one of the most ancient structures in the universe when we examine this cluster.
Originally discovered by James Dunlop in Parramatta and listed as Dunlop 388.

NGC 4945 (Caldwell 83, Hartung 505)
Date 23/1/10 Seeing - Fair
Barred spiral galaxy in Centaurus

From Gamma Centauri (bright star immediately north of Crux) moved in f about 2o to mag 4.5 star e Centauri then further 2o to a right angled trio about 1.5o wide formed by Xi1, Xi2 and f Centauri. Looking slightly f of Xi1 for a faint elongated streak. Galaxy is very obscured by galactic dust and low position isn’t helping visibility. Due to low visibility no obvious structure is evident.
This galaxy was originally discovered By James Dunlop at Parramatta, but I have been unable to trace it’s Dunlop Catalogue designation. It is a Seyfert type 2 galaxy which houses a supermassive black hole in its core and is extremely active, emitting X rays, ultraviolet and infra red in vast amounts due to the matter being swallowed by the black hole.
It is seen as a twin of our own Milky Way, but our home galaxy, while hosting a black hole in its’s core is much less active.

For more info check out http://www.eso.org/public/news/eso0931/

NGC 2775 (Caldwell 48, Hartung 333)
Date 23/1/10 Seeing - Fair
Spiral galaxy in Cancer

Located the ‘head’ of Hydra as group of stars visible to naked eye f side of Procyon. 3 stars form the northern edge of the head, consisting of Delta, Epsilon and Zeta Hydrae. From Zeta Hydrae, about 1.5o f to a close pair then North to a wide pair about 30’ apart consisting of a mag 6 and mag 7 star. Then about 1.75o in f a faint elliptical glow should be detected. There is a line of 3 mag 7 or 8 stars about 1/2O long placed North about 1/2O. No obvious structure. Seemed to be a better view at low power as 24mm at 67x revealed brighter core but 13mm at 115x washed it out. Although this a spiral galaxy, looks elliptical to the eye.

NGC 6101 (Caldwell 107, Hartung 655)
Date 23/1/10 Seeing - Fair
Globular Cluster in Apus

Locate Atria (Alpha Trianguli Australis) by naked eye. Moved Sp to Zeta Trianguli Australis. NGC 6101 is 2O due South. A mag 5.5 star lies 1O SSf from Zeta then move approx 1.4O SSp to a group of 4 stars mag 6.5 to 8. NGC 6101 is just south of following end of this group.
Although at 10’ wide it is a fairly large Globular it is very faint and with low position and light pollution, averted vision was necessary to detect cluster. Will follow observation in a month or two. No structure, but size was evident.
Originally discovered by James Dunlop and listed as number 68 in his catalogue.

NGC2997 (Hartung 353)
Spiral Galaxy in Antlia.

Thanks to Les Dalrymple for including this object his Deep Sky Wonders column in the latest edition of Aus S&T.
Located Lambda Velorum by naked eye. Moved directly north to Psi Velorum which is Sf then about 4O directly north to Epsilon Antliae. Then about similar distance to prominent double in finder which is Zeta1 and Zeta2 Antliae. Then move f to pair of mag 7 stars then to a mag 5.5 star, then a further 2O in f to a 1O wide right angle triangle of mag 6 stars. NGC 2997 lies 1.5O to north of northern star in this group, there is a mag 6.5 and a mag 7.5 star just on f side of galaxy.
Target needs to be high is sky and is fairly large. Core is just visible with direct vision. Moving eye around field revealed halo and arms moving in and out of averted vision. Is almost face on and dark skies will make this a fantastic object.
NGC 2997 is a ‘grand design’ spiral meaning there is a core and arms but no bar. It is about 55 million light years away and is similar in size or slightly smaller than our Milky Way.

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Old 24-01-2010, 06:26 PM
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pgc hunter
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Location: Renmark, SA
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hmmm 5 degrees, isn't that warmer than normal for this time of the year?

NGC 2997 is on top of my list, but I'm betting light pollution will kill any chance of seeing the spiral arms I was going to go out last night aswell but was far too tired so had a night in with a burger and some red wine.

Once again a great write up.

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