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Old 30-12-2009, 12:50 PM
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Location: Renmark, SA
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Observing Report 29/12- More Planetaries

As fate would have it, it was looking like a clear night. However on the horizon as the sun set, some disgusting MELBOURNE CLOUD was seen lurking ominously, just rearing to race in and ruin yet another evening. As it happens, I was interrupted by MELBOURNE CLOUD no less than 3 TIMES durign the course of the night.

Now, besides that, it was certainly a night of good viewing. Seeiing was quite variable again, and the moon was up for most of the night, setting around 2:30am.

Time: 11pm-sunrise
Scope: 12" F4.6 dob
Seeing: 1-7/10
Transparency: 1/5 (moon)
Dew: light, although very heavy in the morning


Started the night off with the Moon. Being in Taurus, seeing in this region of the sky was naturally poor. However, some nice crisp detail was seen at times with the 13mm LVW in the 2x barlow at 216x. Seven craterlets were seen in Plato (A,B,C,D,E) were clearly resolved as pits while (G,H) were seen as tiny white dots. THe "double craterlet" was well resolved.

M79
GC, Lepus, Size = 8.4', Mag V = 7.7

Numerous sparse outlier halo stars with seem to be somewhat detached from the main core of the cluster. The core itself was clearly granular at 176x. A string of 8 Mag 13-14 outlier stars frame the southeastern side of the cluster. At a mag of 216x, not much improvement in resolution was seen, except perhaps more pronounced granularity in the core. Barlowing the 8mm LVW for 353x showed some resolution in the outer 3rd of the core region, with a few pricks of light twinkling in 'n out of vision over the core itself.

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At this point it was around 11.30-11.45pm and to my horror, bloody Melbourne Cloud was screaming in at bloody warp speed. Needless to say, I was about to pass out. Extremely PO'd, I skull a stubbie in record time and watch some TV. About 45 mins later, I see the Melbourne Cloud reducing in size and disgustingness, and yes it is a fantastic feeling! Back out i go.
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Henize 2-7

PNe, Vela, Size = 45", Mag V = 12.4

Easily picked up this Planetary as a tiny bluish orb at 176x. Easily located midway between two 11th mag stars. No real improvement in the view at 283x with the 5mm LVW. Barlowing the 5mm for a magnification of 566x however revealed it to be slightly oval in a N-S direction. THere were suggestions of annularity however I could not confim this. A compact chain of 3 stars of Mag 13 and 14.8 lie just N of the PNe, with the closest only approx 20" NE. The PNe effectively forms the 4th member of this chain. The Dimensions given for this object appear to be misleading as visually it is far smaller.

Wray 17-18
PNe, Vela, Size = 20"

283x/404x - Saw a very compact group of three 14th magnitude stars at its supposed location. Looking at DSS images, these stars are located immediately (approx 30") N of the planetary itself. The nebula not spotted..however not sure if this is because it's too faint or I was concentrating at a spot a few arc seconds away. DSS images show the PNe to be significantly fainter than the 3 stars mentions so it may have infact been too faint considering the moonlight.

ESO 259-10
PNe, Vela, Size = 28"

Using 283x, this planetary was visible as an ill-defined circular haze around a 13-14th mag star. Poor respone to OIII filter. At 404x, a mag 14.5 star was seen at the NW edge of the nebula.

NGC 2792

PNe, Vela, Size = 13", Mag V = 11.8

Fairly bright planetary at 176x, slightly elongated N-S. Using the 3.5mm LVW for a power of 404x suggested annularity. Using the OIII at 404x, the interior of the nebula was definately, but very subtly darker than the outer region and the southern edge of the object was also brighter. Using the 5mm LVW and 2.5x Powermate for 707x, and at this mag I could see a dark region within the nebula which is actually oriented E-W, rather than a circular donut-like struture. The southern edge of the nebula also had a pronouced brightening.

Henize 2-9
PNe, Vela, Size = 4.4"

Very tiny planetary, appearing virtually stellar at all mags up to around 300x. Visible as a tiny disk at 404x. Clearly circular at 707x, with hints of uneven surface brightness.

NGC 3918
PNe, Centaurus, Size = 19", Mag V = 8.5

A favourite of mine! Easily seen as a green disk at 44x. At 404x, the planetary appeared very slightly elongated N-S. At 707x, the N-S elongation of this PNe was clearer, and I could see very faint bulges stretching out from the PNe's E and W sides, with the western one larger and more obvious. This gave the PNe an appearance that could be best described as two cereal bowls stuck together rim-to-rim. The overall surface brightness of the PNe also appeared to be slightly uneven, and the northern edge appeared somewhat brighter than the rest of the object.

NGC 3242 Ghost of Jupiter
PNe, Hydra, Size = 45x36", Nag V = 7.8

Another favourite. Intensely blue. The eye shape and surrounding halo + the central star was clear at 283x. Increasing power to 566x provided a fantastic view, the rim of the eye was beautifully sharp, the corners of the eye were distinctly thicker than the rim, (like the stereotypical impressions you usually find of the human eye). The central star was nice and pinpoint. The outer halo was well defined and uneven in surface brightness, particulary at each "end", where the brightness seemed to drop off.

Also took a look at Mars, and while seeing was playing havoc at times, I did see the South Polar Cap cleary defined at 216x, with a dark feature running along its perimiter. The North Polar cap could also be seen. Numerous dark markings were seen. Couldn't observe in greater detail as clouds were stuffing about.

All in all a good night, despite cloud issues!
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