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Old 02-03-2008, 02:26 PM
§AB
Its only a column of dust

§AB is offline
 
Join Date: Aug 2007
Location: New Iceland
Posts: 761
Observations 2/3/08

Last chance for an all nighter as Uni is starting and my energy will be lost to Friday nights

There was a lot of bloody wind and consequently seeing was pathetic at best. To add insult to injury, the wind was cold enough to kill you. The transparency wasn't great either. A completely different world to the night before. But as I said it will be my last chance to grab some quality eyepiece time until next weekend.

Took the truss dob out, I am getting the hang of setting it up now My mum also devised an ingenious way of transporting the 25kg rocker from my bedroom to the door - slide it on a rug

Time: 11pm-3:00am
Scope 12" (304mm) F4.6 truss dob
Seeing: 3-4/10
Transparency: 3/5
Temp: 10ºC
Dew: nil

Started off doing some unfiltered low power sweeps of Eta Carinae region. At 64x and 83x, just cruised over the whole area enjoying the rich starfields, following the tendrils of Eta Carinae nebula and its numerous associated star clusters and dark lanes. This region is arguably the most funtastic area in the whole sky, only Scorpius and Sagittarius are the other real contenders.

PK288+0.1
I happened to sweep over the location of this planetary and figured I'll have a go at sighting it. It is less than a degree NE of Eta Carinae and lies in a rich starfield. I suspected something without a filter at 176x. I grabbed the OIII and the 5mm LVW for 283x. Seeing was really marginal and this power was too high IMO but the OIII really bought out the planetary. The nebula was slightly oval and donut shaped, the region within the ring was perhaps not completely dark. The ring was unevenly bright, with the brightest portion at its northern edge. This PN is very small and requires very high power to see it well but the bad seeing said no to all that. It also requires an OIII filter to see well.

NGC 3293
Used 83x on this open cluster, noticed that the bright 'central' star is surrounded by an oval ring of fainter stars of almost equal mag. With the exception of the brightest member, the inside of this oval is almost completely empty.

NGC 3114
Very large open cluster west of Eta Carinae. A rich, extended group of mag 8 and fainter stars at low power. Basically covered the whole FOV at 83x. A bright mag 6.5 star lies just SE of the main concentration of stars and another mag 6.5 star lies at the southern extremety.

Leo Triplet - M65, M66, NGC 3628
Leaving Carina (for now!) I decided to check out the Leo triplet. Even though it was relatively low in the northern murk and light pollution, the 3 galaxies showed up really well at 166x! M66 was smaller and fatter than M65. Both were bright with tight cores. NGC 3628 was ofcourse fainter and appeared as a large narrow streak. I could actually make out the dust lane intermittently, quite difficult in the light pollution and poor seeing but it was there!

M105
Not far west of the Leo Triplet is M105. This elliptical galaxy had a bright almost stellar core, with a faint circular haze surrounding it but anything else was washed out by light pollution. The galaxy is part of a tight group of 3, all fitting into the FOV at 166x. NGC 3384 appeared smaller than M105, no hint of its elongation, instead it showed a bright core surrounded by a feeble haze although smaller than M105. The 3rd galaxy is NGC 3389. The faintest of the 3, my 12" picked up considerable NW/SE elongation. Little more than an evenly bright smudge.

Now I took a break, grabbed some coffee and biscuits. So good on a freezing cold night under the stars, with a big lightbucket in your hands. Can life get any better?

UGC 5832
Still in the area, a tiny, faint galaxy located between 2 mag 8-9 stars about 20' SE of NGC 3338. At 166x, I tried and tried, straining for 5 minutes to see if I can pick this Mag 13.8 ghost. I did glimpse something intermittently near a field star, jumping in and out of vision.

NGC 3338
Relatively faint, elongated smudge at 166x with a mag 9 star at its western end. Mag is 10.9 but very low SFC brightness of 14.0.

Now I returned to the Eta Carinae area. The plan was to observe some open clusters and see what the OIII will do for the nebulae here. Goddamn I was in for a shock.....

Starting with the open cluster NGC 3766. Easily found a degree N of Lamba Centauri and forms the 4th component of a chain of three 5th mag stars. There doesn't appear to be much talk of this cluster in observation reports etc but let me tell you it is ONE OF THE BEST in this whole area, IMO second only to NGC 3532. At 108x, it is very rich, tightly packed group. One interesting feature I noticed was an almost perfect semi-circle of 11 equal mag stars all seperated identically. A very pretty sight The center is framed by 6 bright stars arranged in a lopsided triangle.

NGC 4103
Small Open cluster in Crux. At 108x its 8 brightest stars are arranged in a flattened "V" shape with around 2 dozen fainter members clustered around the base ofthe "V".

Melotte 105
Stumbled upon this open cluster while hunting the nebulae only a degree to its east. Despite being an uninspiring tiny dashed circle in the MSA, it is actually quite a pretty sight, I suspect for larger telescopes only as the member stars are quite faint. At 217x, the clump is arranged in an oval, fairly rich with about 40 stars visible. A dark void seems to split the cluster in two, with the smaller section containing around 15 stars.

GUM 41
Viewed with OIII at low power, it appeared as an oval haze around a mag 8.5 star. Gum 41 is basically the southernmost appendage of the Running CHicken Nebula (IC2948).

Homunculus Nebula
Poor seeing meant limited viewing. At 283x, I got instances when it the brightest lobe was remarkably textured and detailed, very jagged. One of the lateral jets streaming out of Eta Carina was obvious.

OIII SWEEP OF ETA CARINAE AND SURROUNDS
Fitting the OIII filter into my 17mm LVW (83x), this is a sight to behold The brightest portion of the nebula was so intristically detailed, loaded with dark areas and bok's, I almost couldn't beleive what I was seeing. The keyhole was really like a black keyhole against the shiny chrome doorknob fitting. That's how clear it was. I took the time to sweep the whole area, just astounding. The nebula could be traced for miles, extending south well beyond the bright star W Carinae, all the way down to the variable HW Carinae. At the other extreme I could find tendrils extending almost out to vdB-Ha 99 and NGC 3324 to the NW. Infact, It could be traced to the exact extent shown in the MSA. I then studied the brightest areas around the Homunculus at 217x, unreal. The detail is just mindblowing. All those dark bays,regions and undulations in brightness all pitch black against the bright greenish hue of the nebula. And the best part of it all - this was WITH THE MOON WELL ABOVE THE HORIZON I can't even imagine what I'd see at a dark sky site with no moon!



Got some sketches, coming soon.
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