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Old 25-05-2017, 09:43 PM
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DeepSkyBagger (Patrick)
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Eight Galaxies, Four Clusters, Horrible Night

I had a clear night last night, but at 53.5 degrees north, I'm into Astronomical Twilight, when the sun never gets far enough below the horizon to produce an astronomically dark sky. Checking my observing programme, I realised that in the dim (not dark) portion of the night, I only had mag 13 galaxies to look at, and as the humidity was high and there appeared to be thin, hazy cloud all over the sky, I decided not to bother. Depressing.

My last 'clear' night was Tuesday 25th April. Well, it looked clear, but so claggy! I just about managed to bag seven galaxies:

NGC 4032: mag 12.2, SB 13.3 Irregular in Com
Incredibly faint. Barely visible, just a small, round ghost. No central brightening.

NGC 4045: mag 12.0, SB 13.6 Spiral in Vir
Not easy. Round or slightly elongated and very, very little brighter towards the middle.

NGC 4073: mag 11.4, SB 12.6 Elliptical in Vir
Almost entirely seen with averted vision. Very faint, just a little local brightening of the background sky. Round or possibly slightly elongated. No central brightening seen.

NGC 4096: mag 10.8, SB 13.3 Spiral in UMa
Very large but pathetically dim on this feeble night. Very highly elongated. Very slightly brighter towards the middle. Occasionally, averted vision suggested a brighter spot north east of the centre.

NGC 4100: mag 11.2, SB 13.4 Spiral in UMa
The only galaxy seen this night which was visible at x83 finding power - and the only Herschel type III!. Pretty faint, large and very, very elongated, almost like a splinter. Slightly brighter towards the middle.

NGC 4124: mag 11.3, SB 13.5 Spiral in Vir (=4119)
Incredibly difficult. Large and thin - highly elongated. Absolutely nothing else visible through these rubbish skies.

NGC 6661: mag 12.1, SB 12.8 Spiral in Her (=6660)
Pretty faint. Small, oval. Slightly brighter towards the middle.

These objects should have been much easier than this, even from my fairly poor observing location. I decided to give up on the galaxies and look at some clusters instead. Even then, the Milky Way hunting grounds were still low, and I had to content myself with a few obscure objects in Lyra, just climbing out of the eastern LP.

NGC 6734: Uncertain cluster or possibly an asterism. x83 reveals a triangle of fairly bright stars in a rich Milky Way field. x150 shows the triangle to be made up of the brightest stars in a little group, coarse but moderately well detached. Maybe 30 stars, in clumps, seen over 10 - 12' diameter.

Stephenson 1: Clustered around δ1 and δ2 Lyrae, this is a very bright but poor cluster. Several bright stars are spread across the 36' field with fainter ones scattered amongst them. Although very loose, it stands out well from the Milky Way background on low power, so pretty well detached. About 70 stars were counted in the 36' field.

ASCC 100: I can't find anything about this object in any reference work. It's not in Archinal & Hynes. Not plotted on Guide, but listed in the OVOC catalogue. Its location is 19h 01m 37s +33° 34'.1. Centred on 6.4 magnitude SAO 67721. There is a bright quadrilateral of stars here, 19' long on its longest axis. Amongst them, and skewed towards 67721 (one of the corners of the quadrilateral) is a concentration of fainter stars, typically 11th and 12th magnitude. A comparison with surrounding fields shows that there is an increase in the number of stars of this brightness here. It looks like a local Milky Way clumping.

ASCC 101: AKA LeDrew 6. Very similar to nearby ASCC 100. A noticeable concentration of 11th and 12th magnitude stars around some brighter ones across a large diameter. Nicely framed in the x60, 50' field. The brightest of the stars is 7.1 magnitude SAO 68013, spectral type A0.

I had a try at one more galaxy-

NGC 6674: mag 12.2, SB 14.4 Barred spiral in Her
This was a very poor view, almost a 'Not Seen'. I didn't bother making an observation, it wasn't worth it.

All the observations I made of galaxies I have flagged as 'POR' on my observing programme - 'Poor observation, re-observe'.

The clusters were fun, but overall a very disappointing night. The NELM was 4.7, the temperature +1 Celsius and the humidity over 80%. Horrible.
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  #2  
Old 31-05-2017, 01:10 PM
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Tinderboxsky (Steve)
I can see clearly now ...

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I enjoyed reading your report Patrick. Poor observing conditions are the devil himself.
I always remind myself of the three "p's" - practice, patience and persistance.
What equipment are you observing with?
Cheers
Steve.
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Old 01-06-2017, 12:47 AM
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DeepSkyBagger (Patrick)
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Hi Steve,

In a similar vein, I'm also always aware of the 6P rule: Proper Preparation Prevents Pretty Poor Performance. Of course, you can replace 'Pretty' with a more forceful word if you like :-)

I observe with a 12" SkyWatcher flextube. It's driven and has Goto capability. I spent 35 years as a star-hopper, and five years ago, I decided that I'd earned a Goto! Of course it never quite hits the right spot, and I find myself 'microhopping' to the right field. I suppose it keeps me in practice!

Cheers,
Patrick
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