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Old 19-05-2015, 09:39 PM
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Location: Renmark, SA
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Observing Report 17 May 2015

A nice evening under the stars finally provided some surprises and interesting viewing. Bought myself one of those fold up tables from Bunnings for use at the scope, why I didn't do that earlier I'll never know! These obs were done with my 8" F/6 dob.

Scope: 8" F/6 dob
Time: 1930-0030
Seeing: Ant. II
Transparency: 4/5
Dew: Heavy

IC 2944 Running Chicken Nebula
BN, Centaurus, RA 11h 36' 36", Dec -63*02'00", Size= 75'

A low surface brightness amorphous haze at 54x surrounding an elongated roughly 20' long bar of several mag 7-11 stars 30' SE of lamba Centauri. Adding the UHC filter really brings out the nebulosity. The nebulosity appeared brightest along the southern edge of the "star bar" with a wide plume extending south. An uneven surface brightness was evident in the nebulous region around the star bar and a stubby filament was seen extending N and slightly curving W of a mag 7.6 double star at the SE end of the star bar.

The nearby nebula Gum 39 was seen with the UHC as a small faint haze, perhaps slightly elongated NE-SW adjacent to the NW of a mag 8.3 star.

Mel 105
OC, Carina, RA 11h 20' 6.5", Dec -63*34'24", Size= 5x5', Mag V=9.4

Stumbled upon this open cluster with the OIII still in the 54x eyepiece while scanning the region. Looked surprising bright, granular with a background haze for a somewhat dim cluster at low power with on OIII in place. Removed the OIII and interestingly did not appear brighter as I expected for a star cluster. About a dozen stars resolved superimposed on faint haze arranged in a fat crescent with the 2' long axis orientated N-S.

A magnification of 150x increased resolution to about 2 dozen stars, the brightest smattered against background haze in the crescent shape with a second loosely packed group of a half dozen stars sitting adjacent to the N/NW seperated by a narrow dark rift. Photos don't show any form of nebulosity associated with this cluster, so not sure why it popped so well with the OIII in place. Interesting.

Cederblad 122
BN, Centaurus, RA 13h 24'07" , Dec -64*01'

Here is an interesting object. This is shown as a bright nebula in the Millenium Star Atlas, while Simbad lists it as "interstellar Matter". Images do show nebulosity amongst thick starfields. It is located just east of the Coalsack.

At 54x, this region is awash in rich starfields. Mag 4.5 M Centauri and its mag 5.3 companion 8.5' to the ENE provide a good anchor point for observation. Sweeping the field, mostly to the NE of M Centauri there appeared to be uneven surface brightness suggesting either nebulosity of simply unresolved Milkyway starfields. Most prominent is a wide swath just to the north of the faint cluster Cr 271. Another portion lies orientated N-S WNW of a mag 7 star located 51' NE of M Centauri. A somewhat darker elongated N-S void was seen bordering to the west of this particular swath of haze. A slightly less obvious hazy region was seen between 2 mag~ 7.5 stars just NW of M Centauri and the void. Another fainter extended swath of haze was seen extending to the S/SE of a flattened triangle of mag 9-10 stars at the northern end of the complex to the northern edge of the void.

Adding the UHC enhanced this faint nebulosity and the aforementioned dark void became more obvious as a fat sausage shaped region extending N-S perhaps 1/2 degree. With the haze seemingly enhanced by the UHC, this would suggest that I was actually seeing nebulosity.

M83
GX, Hydra, RA 13h 37'00", Dec -29*52'04", Size= 15.4x13.1' , Mag V= 7.8, SB= 13.0

No luck seeing spiral arms at 92x however I suspected uneven surface brightness. Fairly large round haze bordered by three mag ~10 stars adjacent to the the SE. I did however see the main bar which appeared to have higher surface brightness than the surrounding haze. This galaxy exhibited a tight compact and bright core with a faint star at the W edge of the outer haze and another fainter star equidistant to the E.

ESO 97-G13 Circinus Galaxy
GX, Circinus, RA 14h 13'9.9", Dec -65*20'21", Size= 8.8x4.3' , Mag V= 10.6

This one is interesting. At 150x, I could see a small smudge only 49" W of a mag 11.6 star. A second similar smudge could be seen a similar angular distance WSW of the first smudge. Hang on, isn't this supposed to be a single galaxy? The western object appeared to be elongated SW-NE and slightly higher surface brightness than its neighbour, with a stellaring seen in a condensed core.

At 240x, the stellaring in the west object appeared clearer as did the elongation. A second very faint stellaring was seen just east of the main one. According to Cartes Du Ciel, they are seperated by 6" and have magnitudes of 12.7 and 14.05. At this magnification I suspected a mild N-S elongation in the eastern object (the one adjacent the aforementioned mag 11.6 star) and a slight brightening towards the core.

Looking at DSS images, there is only one galaxy. The eastern object is the "real" core of the galaxy, while the western object is infact a tight clump of 4-5 faint stars that perhaps blended together at the eyepiece giving the effect of haze, much like in a globular cluster, with only two of them bright enough to be resolved. Really did look like two seperate galaxy cores in the eyepiece!

HICKSON 62
NGC 4778
GX, Virgo, RA 12h 53'06", Dec -9*12'17", Size= 1.8x1.4' (4778/4776 combined) , Mag V= 13.0, SB= 13.3

NGC 4776
GX, Virgo, RA 12h 53'4.4", Dec -9*11'56", Mag V= 13.0, SB= 14.2

This is a double system and forms the brightest component on Hickson 62. Located 2' N of a mag 9.4 star which proved distracting during observation. Appeared as a faint, irregular clump at 150x. Suspected seperation at 240x. NNGC 4761 1' E was not seen.

NGC 5248
GX, Bootes, RA 13h 37'32", Dec +08*53'08", Size= 6.2x4.5", Mag V= 10.3, SB= 13.5

Easily picked up at 54x as a moderate sized oval haze elongated NW-SE 2:1. Positioned at the corner of a right angled triangle with two mag ~11 stars located 8.5' NW and 6' SSW. Compact, elongated, dense core at 150x surrounded by a faint oval haze elongated 2:1 and orientated NW-SE. Faint mag 13.7 star was seen 1.45' S of core.

NGC 5775
GX, Virgo, RA 14h 53'57", Dec +03*32'41", Size= 4.2x1.0' , Mag V= 11.4, SB=12.8

Highly elongated streak at 150x. A mag 13.8 star lies just 55" NE of the centre. At 240x a slight brightening towards the core was evident. Nearby NGC 5774 was not seen.

To finish off the session I went for a cruise around the Sagittarius Milky Way with the 54x eyepiece and the UHC. The Lagoon Nebula (M8) was absolutely exquisite, I don't think I've seen it so beautiful before. The whole field was awash in its fainter outer plumes. The Trifid (M20) was fantastic aswell, its dark lanes clearly visible. One can see what appear to be faint swathes of nebulosity in the area as you sweep the region. Stumbled upon M17 aswell and that shape was knife-edged, very bright with detail and faint plumes extending beyond the tail-end of the "Swan" or Omega (whatever you prefer to call it) and looping back around. Called it a night here as the dew was starting to get ridiculous.

This fold out table is a life saver!
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Last edited by pgc hunter; 20-05-2015 at 01:23 AM.
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